NTS 2019 Past MDCAT Paper With Explanation

[Shahid]

QUESTION: Choose the word most similar in meaning to the capitalized one. DEMONSTRATE:
A. Establish
B. Invent
C. Produce
D. Show
EXPLANATION
Demonstrate refers to displaying something. Option D is the best choice here which is a synonym of the word display.

QUESTION: Choose the word most similar in meaning to the capitalized one. FLEE
A. Escape
B. Face
C. Fear
D. Flow
EXPLANATION
Flee means to run away from something, usually a duel or battle. Escape is the only option which fits description well.

QUESTION: Choose the word most similar in meaning to the capitalized one. UNAMBIGUOUS:
A. Exact
B. Clear
C. Interesting
D. Sufficient
EXPLANATION
Ambiguity refers to something being not clear and easily understood. Since the word here is Unambiguous, the word clear is the closest in meaning to it.

QUESTION: Choose the word most similar in meaning to the capitalized one. LEGEND:
A.  History
B. Outburst
C. Place
D. Story
EXPLANATION
Legend refers to a traditional story and a tale about something. Hence, Option D is correct.

QUESTION:  Read the passage and answer the following question: That freedom means freedom only from foreign domination, is an outworn idea. It is not merely governments that should be free but the people themselves who should be free; and no freedom has any real value for the common man or woman unless it means freedom from want, freedom from disease, freedom from ignorance. This is the main task that confronts us if we are to take our rightful place in the modern world. We cannot hold the clock back, and there it is we who must go forward at a double pace bending all our resources and all our energies to this great purpose. An ‘’outworn’’ idea is?
A. Great
B. Not new
C. Scientific
D. Undeveloped
EXPLANATION
The context of the passage can be used to choose the correct answer for this question. The way outworn is used, it clearly indicates something not being new and modern.

QUESTION:  Read the passage and answer the following question: That freedom means freedom only from foreign domination, is an outworn idea. It is not merely governments that should be free but the people themselves who should be free; and no freedom has any real value for the common man or woman unless it means freedom from want, freedom from disease, freedom from ignorance. This is the main task that confronts us if we are to take our rightful place in the modern world. We cannot hold the clock back, and there it is we who must go forward at a double pace bending all our resources and all our energies to this great purpose. The great purpose mentioned by the writer at the end of the passage refers to:
A. Freedom from foregin domination
B. People themselves should be free
C. The real value of freedom
D. Taking our rightful place in the modern world.
EXPLANATION
The passage clearly mentions the answer to this. At the end of the passage he refers to it again which confirms our answer again.

QUESTION: Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters. BRILLIANT
A. Adequate
B. Dull
C. Troubled
D. Unprejudiced
EXPLANATION
Brilliant refers to something being extraordinary and very bright. Dull is the best antonym for bright

QUESTION: Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters. ENFEEBLED:
A. Distanced
B. Dominant
C. Mistaken
D. Powerful
EXPLANATION
Feeble means something lacking physical strength and being weak.

QUESTION:  Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters. UNLIKELY:
A. Familiar
B. Possible
C. Powerful
D. Take for granted
EXPLANATION
Unlikely refers to something that has low chances of occurring with a low probability. Possible is the direct opposite of it which means something is very likely to occur.

QUESTION: Read the passage and answer the following question: Anglo-Saxon is now, of course, a dead language, but a good deal of its vocabulary has survived, in one form or another to the present day. Most of the very common words in modern English are Anglo-Saxon in origin; nouns like father, mother, food, drink, bed, hunger; most of the prepositions and conjunctions; and nearly all the strong verbs. When it was mixed with Norman French, there were three main results: the grammar was simplified, the pronunciation and spellings became much more complicated and the vocabulary was enormously extended. French is a Latin language, so the major part of our vocabulary is now Latin in origin. A “dead language” is:
A. A dialect of language
B. Latin language
C. Mixed with other languages
D. No more spoken
EXPLANATION
This is a figure of speech, reading the context of the passage one can decipher it clearly means that it is no longer used in everyday life.

QUESTION: Read the passage and answer the following question: Anglio - Saxon is now, of course, a dead language, but a good deal of its vocabulary has survived, in one form or another to the present day. Most of the very common words in modern English are Anglo - Saxon in origin; nouns like father, mother, food, drink, bed, hunger; most of the prepositions and conjunctions; and nearly all the strong verbs. When it was mixed with Norman French, there were three main results: the grammar was simplified, the pronunciation and spellings became much more complicated and the vocabulary was enormously extended. French is a Latin language, so the major part of our vocabulary is now Latin in origin. The vocabulary was “enormously extended” means vocabulary has:
A. Increased
B. Reduced
C. Simplified
D. Survived
EXPLANATION
Extended refers to prolonging something, increasing something. Hence Option A is the correct answer.

QUESTION: Identify the word or phrase that needs to be changed for the sentence to be correct. When I go into a bank, I get frighten.
A. When
B. A
C. Get
D. Frighten
EXPLANATION
The key to solving these questions is reading them in your head and deciphering which part sounds odd. Frighten is clearly used wrongly over here. It could have been “Banks frighten me”, but here it should be frightened.

QUESTION: Identify the word or phrase that needs to be changed for the sentence to be correct. The fact of the matter is never I’d been out to the theatre that night, had supper afterwards, and came in late.
A. Never
B. That
C. Late
D. Afterwards
EXPLANATION
The key to solving these questions is reading them in your head and deciphering which part sounds odd. If you remove the word never, the sentences make much more sense.

QUESTION: Identify the word or phrase that needs to be changed for the sentence to be correct. In Maxwell’s days, no instruments had been made which could register the greatly enormously long waves of electricity.
A. No
B. Could
C. Greatly
D. Wrong
EXPLANATION
The key to solving these questions is reading them in your head and deciphering which part sounds odd. It could have been “greatly enormous” long waves. But if enormous also ends with a -ly then it should be great instead.

QUESTION: Identify the word or phrase that needs to be changed for the sentence to be correct. This long experience of European domination has naturally produced a mood of quite resistance.
A.  This
B. Long
C. European
D. Quite
EXPLANATION
Over here quite is wrongly used as the other homophone (quiet) was the intended word. Meaning the resistance is very quietly developing in secret. Quite is an adverb used to describe when something is a little or a lot but not completely. Quiet is an adjective used to describe something or someone that makes very little noise.

QUESTION: Complete the sentences by choosing the most appropriate option, from the given lettered choices (A to D) below each: The house ______ before we moved in.
A. Paint
B. Painted
C. Has painted
D. Was painted
EXPLANATION
The key to solving these questions is reading them in your head filling in each option and then deciphering which option fits in well. The sentence here is clearly in the past tense hence Option D is the correct option as it indicates the house was painted.

QUESTION: Complete the sentences by choosing the most appropriate option, from the given lettered choices (A to D) below each: Her hair was hanging ______ her back.
A. Beyond
B. By
C. Down
D. From
EXPLANATION
The key to solving these questions is reading them in your head, filling in each option and then deciphering which option fits in well. For any sentence which refers to something hanging, down is the most suitable preposition.

QUESTION: Complete the sentences by choosing the most appropriate option, from the given lettered choices (A to D) below each: We must ______ back by six o’clock.
A. Be
B. Can
C. Has
D. Have
EXPLANATION
The key to solving these questions is reading them in your head, filling in each option and then deciphering which option fits in well. Be is the only option that fits in well

QUESTION:  Complete the sentences by choosing the most appropriate option, from the given lettered choices (A to D) below each: Birds usually ______ eggs in their nests.
A. Laid
B. Lain
C. Lay
D. Lie
EXPLANATION
The word usually indicates the sentence to be in the present tense. Lay is the correct word here as it means to put down something. Lie refers to not speaking the truth.

QUESTION:  Choose the lettered word or phrase that is most nearly opposite in meaning to the word in capital letters. INVADERS:
A. Characteristics
B. Historians
C. Inhabitants
D. Results
EXPLANATION
Invaders refer to people who attack any area and then become new settlers. Inhabitants refer to the people who had been living in the area before.

QUESTION: In sexual reproduction, sex cells contain _____ chromosomes when compared to other cells of the body
A. same
B. half
C. double
D. all of the above
EXPLANATION
The sex cells are formed as a result of meiosis(reduction division) which causes the original normal chromosome number of the cell (2n) to be divided to become half (n)

QUESTION: During cell division, the spindle fibres get attached to condensing chromosome at a highly differentiated region. This region is called as:
A. Chromosome
B. Chromocentre
C. Centriole
D. Kinetochore
EXPLANATION
The key feature of metaphase is the attachment of spindle fibers to kinetochores of chromosomes. Kinetochores are disc-shaped structure at the surface of the centromeres. These structures serve as the site of attachment of spindle fibres to the chromosomes that are moved toward poles. So, the correct answer is Kinetochore.

QUESTION: Pituitary gland releases ______ hormone and _______ hormone while ovaries produce _______ and progesterone.
A. Follicle-stimulating and luteinizing, estrogen
B. Estrogen and follicle-stimulating, luteinizing
C. Luteinizing arid estrogen, follicle-stimulating
D.  Follicle-stimulating and estrogen, luteinizing
EXPLANATION
The pituitary gland releases the follicle-stimulating hormone and luteinizing hormone while ovaries produce estrogen and progesterone.

QUESTION: In higher animals bodies, tissue fluid is isotonic as contrary to plants because in plants cell:
A. Cell membrane creates resistance in water uptake
B. Plastids create resistance in water uptake
C. Chlorophyll creates resistance in water uptake
D. Cell wall creates resistance in water uptake
EXPLANATION
In-plant cells, there is an additional potential exerted by the cell wall from the outside that increases the overall osmotic potential inside. This effect of pressure potential in plant cells is not seen in animal cells due to the absence of cell walls, even though the solute potential inside and outside of the cells are not equal, still, osmotic potentials are equal.

QUESTION: Which one is NOT an involuntary function
A. Breathing
B.  Pumping of blood
C. Skeletal muscle movement
D. Blinking of eyes
EXPLANATION
Involuntary functions are those that occur without our conscious control. Skeletal muscle movement is not an involuntary function;it is voluntary/intentional. Blinking of eyes, heart-pumping of blood, and breathing are all involuntary.

QUESTION: In gametogenesis, which resultant product is non-functional?
A. Spermatogonia
B. Oogonia
C. Polar body
D. Ovum
EXPLANATION
A polar body is a small haploid cell that is formed concomitantly as an egg cell during oogenesis but generally does not have the ability to be fertilized.

QUESTION: The passageways of the respiratory system mucous secreting cells called:
A. Tracheal cells
B. Goblet cells
C. Surfactant cells
D. Pleural cells
EXPLANATION
The primary function of goblet cells is to synthesize and secrete mucus. Pleural cells line the pleural cavity which has nothing to do with the respiratory passageway. Surfactant cells line the alveoli that release a key component, surfactant, whose main function is to reduce surface tension. Tracheal cells are of two types goblet cells and ciliated cells. Tracheal cells are not specifically mucous secreting cells but involve ciliated cells too.

QUESTION: The virus can only survive and reproduce inside a:
A. Animal Cell
B.  Bacterial cell
C. Living cell
D. Non-living cell
EXPLANATION
Viruses can reproduce in any living cell by using its genetic machinery.

QUESTION: In addition to smaller hind limb muscle mass, the mutant mini Muscle” gene exhibits lower heart rates during physical activity, larger kidneys and livers in mice. This is a very good example of _______.
A. Epistasis
B.  Multiple alleles
C. Codominance
D. Pleiotropy
EXPLANATION
Pleiotropy occurs when one gene influences two or more seemingly unrelated phenotypic traits. Here we can see that the mutant mini muscle gene not only alters the hind limb muscles but has its effect on kidneys, liver, and heart rate maintaining cells.

QUESTION: _______ is the stage of mitosis characterized by the physical separation of ________ chromatids.
A. Interphase. Offspring
B.  Telophase, F1 chromatids
C. Metaphase, Homologous
D.  Anaphase. Sister
EXPLANATION
Anaphase is the stage where the physical separation of sister chromatids occurs. This does not occur in metaphase, in metaphase, the chromosomes only get lined at the equator. In telophase, the chromatids have already reached the poles. In interphase, the chromosomes get condensed only. Hence, all options except option D are wrong.

QUESTION: A man who has type AB blood cannot father a child with type ___ blood, because he would pass on either the ___ or the B allele to all of his offspring.
A. A,O
B. O,A
C. B, O
D. B, A
EXPLANATION
The father can pass on either the A or B allele to each of his offspring.  Even if the mother has blood type O, the child cannot have blood type O because of the A or B allele received from the father. A and B alleles are dominant over O. For blood type O (the recessive phenotype) to occur, there should be two copies of the O allele, one from each parent. This is impossible in the given situation.

QUESTION: Identify purine and pyrimidines from the following figures
A. A and B purines, C, D, and E pyrimidines.
B. D and B purines, C, A, and E pyrimidines.
C.  A and E purines,  C, D, and B pyrimidines.
D. A and C purines, B, D, and E pyrimidines.
EXPLANATION
Purines are those bases that are double-ringed. Pyrimidines have a single ring.  As we can see, A and C are double-ringed so they are purines. On the other hand, B, E, and D are single rings so they are pyrimidines.

QUESTION: A cross between a black cat and a tan cat produces a tabby pattern (black and tan fur together). What percent of kittens would have tan fur if a tabby cat is crossed with a black cat?
A. 100%
B. 50%
C. 25%
D. 0%
EXPLANATION
Tabby cats are hybrids (because they have both colours) & a black cat must be homozygous black. So the cross for this problem is BB (black) x BT (tabby). The results show that 50% of the offspring will be BB (black) & 50% will be tabby (BT). So to answer the question, 0% of the kittens will be tan.

QUESTION: Which factor decides what type of variation should be flourished and passed on to the next generations?
A.  Species
B. Population
C. Survival
D. Environment
EXPLANATION
The environment surrounding the species decides, by putting stress/selection pressure on a particular variation, whether it will flourish or it will vanish.

QUESTION: Haemophilia is a sex-linked _____ trait.
A. Dominant
B. Codominant
C. Pleiotropic
D. Recessive
EXPLANATION
Haemophilia is a sex-linked recessive disorder. The abnormal gene responsible for haemophilia is carried on the X chromosome. Recessiveness is proved by the fact that when a woman has this gene on one X and a normal gene on the other X (heterozygous for haemophilia), she does not show haemophilia in phenotype.

QUESTION: Which of the following is a type of cell division that plays an important role in evolution?
A. meiosis
B. mitosis
C. apoptosis
D. amitosis
EXPLANATION
Meiosis plays a very important role in evolution as meiosis helps bring in more variation of genes by independent assortment and crossing over during it.

QUESTION: The d and D alleles are used for lighter and darker skin colour in humans, respectively. By keeping in view the inheritance pattern of skin colour in human beings, choose which combination showing medium skin colour from the following picture:
A. Column A
B. Column C
C.  Row B
D. Row C
EXPLANATION
The inheritance pattern in human beings exhibits multiple gene inheritance patterns, which means they interact additively and influence other genes in phenotype. Row b is correct

QUESTION: There existed two varieties of female freshwater Mollusks in which some were streamlined and some had a high bulge. Over the generations, male freshwater Mollusks learned that high bulge favors more production of offspring. So they started preferring to mate with females having high bulge as compared to streamlined. Will this affect Hardy Weinberg Equilibrium in the population?
A. No, it will not affect the Hardy Weinberg equilibrium
B. Yes, it will affect the Hardy Weinberg equilibrium
C. It will help to balance equilibrium
D. The Hardy Weinberg equilibrium doesnt apply here
EXPLANATION
One of the assumptions of the Hardy-Weinberg principle is that there is random mating among the individuals of species. The idea of male molluscs preferring high bulge over streamlined negates the idea of random mating, which affects the principle.

QUESTION: A/An _______ is mostly a non-protein chemical compound that is required for the protein’s biological activity.
A.   Active site
B. Substrate
C. Cofactor
D. Enzyme
EXPLANATION
A cofactor is a non-protein chemical compound that is bound to a protein and is required for the proteins biological activity. These proteins are commonly enzymes. Cofactors can be considered “helper molecules” that assist in biochemical transformations.

QUESTION: All of the following are the characteristics of the kingdom Protista except:
A. Members can be photosynthetic
B. Members can be free living
C. Some members move via flagella
D. Some members are shaped like rods and termed bacilli
E. Some members spend part of their life cycle inside insects
EXPLANATION
Protists are a group of loosely connected, mostly unicellular eukaryotic organisms that are not plants, animals or fungi. There is no single feature such as evolutionary history or morphology common to all these organisms and they are unofficially placed under a separate kingdom called Protista. Among the given characteristics rod shaped cells called Bacilli (Bacillus singular) are an exclusive classification of Bacteria. Hence, the correct answer is Some members are shaped like rods and termed bacilli.

QUESTION: Why do some vegetables lose water when salt is applied to them?
A. Due to the less negative water potential of the external environment than the cell.
B.  Due to the more negative water potential of the external environment that the cell
C. . Due to the less positive water potential of the external environment than the cell
D. Due to more positive water potential of the external environment than the cell
EXPLANATION
Water potential becomes more negative with solutes (salt) (less negative with purity). When salt is applied to the vegetable the osmotic (water) potential of the external surface of vegetables becomes more negative as a result of which water moves down the water potential gradient out of the cell, making them lose water.

QUESTION: What type of protein is present in eukaryotic DNA but NOT in prokaryotic DNA?
A.  Receptor protein
B. Glycoprotein
C.  Chromatid protein
D. Histone protein
EXPLANATION
Eukaryotes wrap their DNA around proteins called histones to help package the DNA into smaller spaces, most prokaryotes do not have histones (with the exception of those species in the domain Archaea).

QUESTION: Whenever a muscle contracts, a sarcomere can be shortened up to _____ % of its total length.
A. 15
B. 25
C. 35
D. 45
EXPLANATION
Sarcomere length is reduced by only about 35% (to a little under 2 mm) by a maximal shortening of the muscle.

QUESTION: The second stage of the Prophase of Meiosis, following Leptotene, during which homologous chromosomes begin to pair is called:
A. Anaphase
B. Zygotene
C. Diplotene
D. Pachytene
EXPLANATION
Prophase 1 of Meiosis is the first stage of meiosis and is defined by five different phases; Leptotene, Zygotene, Pachytene, Diplotene, and Diakinesis (in that order). Zygotene (the second stage) is the one in which homologous chromosomes start to pair up.

QUESTION:  Formation of _____ will be greater with the faster breakdown of glucose and glycogen to compensate for energy requirements in aerobic respiration
A. Enzymes
B. Hormones
C. Lactic acid
D. Fat
EXPLANATION
To compensate for the energy requirements of aerobic respiration, anaerobic respiration occurs which leads to the production of a high amount of lactic acid.

QUESTION:  A strand, almost _____ nucleotides long is wrapped around a core of ______ histone proteins to form a structure called a Nucleosome.
A. 200 - 4
B. 200 - 8
C. 200 - 16
D.  200 - 40
EXPLANATION
A strand of 200 nucleotides long are wrapped twice around a core of eight histone proteins to form a structure called a nucleosome. The histone octamer at the centre of the nucleosome is formed from two units each of histones H2A, H2B, H3, and H4.

QUESTION: A group of biologically active molecules formed from amino acids which interact with the surface of the lipid bilayer of cell membranes are called:
A. Integral Proteins
B. Peripheral proteins
C. Cell wall
D. Plasmodesmata
EXPLANATION
Peripheral proteins, or peripheral membrane proteins, are a group of biologically active molecules formed from amino acids which interact with the surface of the lipid bilayer of cell membranes. Unlike integral membrane proteins, peripheral proteins do not enter into the hydrophobic space within the cell membrane. Instead, peripheral proteins have specific sequences of amino acids which allow them to attract to the phosphate heads of the lipid molecules or to integral proteins.

QUESTION: Transport of three protons through the ATPase complex is required for the production of one ______.
A. Sugar molecule
B. NADP molecule
C. ATP molecule.
D. NADPH molecule
EXPLANATION
The H+/ATP ratio, defined as the number of protons necessary to synthesize one ATP at equilibrium, is three. Three protons H+ move through the ATPase complex to generate energy that is used to condensing ADP + Pi to form ATP.

QUESTION:  In a forest, there are a lot of plants; trees, shrubs, and herbs. What will the Palm trees face if they grow in the same forest?
A. Intraspecific competition.
B. Interspecific competition
C. Environmental competition
D.  All of the above
EXPLANATION
In a forest, palm trees have to face all sorts of competition (intraspecific, interspecific, and environmental). Intraspecific competition is a competition of a species among its own type, palm trees will have to face competition from other palm trees already in that forest. Interspecific competition is competition among different species, palm trees will have to face competition from other species. Environmental competition is the competition exerted by the environment (availability of light, water, and nutrients) on species. Hence option D is correct.

QUESTION: Which one of the following options is NOT an example of genetic engineering?
A. Insulin-producing bacteria
B. Oil eating bacteria
C. Photosynthetic bacteria
D. Metal extracting bacteria
EXPLANATION
For bacterias to be photosynthetic they do not need to be genetically programmed. There are naturally occurring photosynthetic bacterias. But, other bacterias such as insulin-producing, oil-eating, and metal extracting ones are those that do not occur naturally; they need to be genetically programmed to do so.

QUESTION: Pick the odd one out in the following picture.
A. A
B. B
C. C
D. D
EXPLANATION
This picture has all requirements (tRNA,mRNA, and ribosome) for the protein synthesis (translation) to happen except RNA polymerase, which is a tool required for transcription, not for translation.

QUESTION: While working in a laboratory, before studying a sample under the microscope, it was immersed in a dye solution to obtain ______.
A. Magnification
B. Image
C. Match
D. Contrast
EXPLANATION
Staining is a technique used to enhance contrast in samples, generally at the microscopic level. Stains and dyes are frequently used in histology (the study of tissue under the microscope)

QUESTION:  Pathway of energy used by muscles converted from food is:
A. Food-ATP-creatine phosphate- protein
B. Food-glycogen- ATP-creatine phosphate
C. Food-glycogen-creatine phosphate- ATP
D. Food-protein-creatine phosphate- ATP
EXPLANATION
Muscles convert food to energy by first breaking down glycogen to glucose. Glucose is then used to form creatine phosphate which is then metabolized to form ATP.

QUESTION: A/An ______ is an organism that makes ATP by aerobic respiration if oxygen is present, but is capable of switching to fermentation if oxygen is absent.
A. Cellular anaerobe
B. Respiratory anaerobe
C. Obligate anaerobe
D. Facultative anaerobe
EXPLANATION
Facultative anaerobes are bacteria that can grow in both the presence or absence of oxygen. In addition to oxygen concentration, the oxygen reduction potential of the growth medium influences bacterial growth. The oxygen reduction potential is a relative measure of the oxidizing or reducing capacity Obligate anaerobes are those that carry out anaerobic respiration only and can not carry out aerobic respiration even in presence of oxygen. Cellular anaerobes and respiratory anaerobes are terms not used to designate any type of organism.

QUESTION: Choose the best group from the following to produce transgenic plants in the laboratory:
A.  Group a
B. Group b
C. Group b and c
D. Group c
EXPLANATION
Group A is correct because it has all the tools required to engineer a plant cell. Restriction enzymes are used to cut out a piece of DNA.DNA ligases are used to engineer, take that cue out gene into the protoplast. Group B is wrong because we do not have plasmids here or any other transmitting agent; plastids are chlorophyll-containing pigments only. Group C can also not be correct for the same reason. Autoradiograph also does not have any function in the engineering of genes in plant cells.

QUESTION: Which one of the following is NOT a mode of transmission of AIDS?
A. Through unsterilized needles
B. Through contact with open wounds
C. Through blood transfusion
D. Through holding hands
EXPLANATION
AIDS is a disease that is caused by HIV that is transmitted from person to person through the mixing of body fluids between two human beings. Option D says holding hands that do not involve mixing of body fluids, unlike other options that do involve mixing of body fluids.

QUESTION: The following results of a cross between two individuals shown in the picture is:
A.  One that is homozygous dominant and the other has a dominant phenotype, but has a mother with recessive phenotype
B. One that is homozygous recessive and other has a dominant phenotype, but has a mother with recessive phenotype.
C. One that is homozygous recessive and other has a dominant phenotype, but has a brother with recessive phenotype.
D. One that is homozygous recessive and another has a recessive phenotype. but has a father with a dominant phenotype.
EXPLANATION
All statements describing the children’s genetic combination and phenotype are wrong except B and C. One child is homozygous recessive with recessive phenotype and the other is heterozygous with a dominant phenotype. Option A is wrong because it says one child is homozygous dominant whereas according to the box diagram there is no possibility that a child will be homozygous dominant. Option D is wrong because it says one child, apart from one being homozygous recessive, has a recessive phenotype, which is wrong. Option C is wrong because it assumes the gender by saying “brother” but the question does not provide any evidence for what the gender of another offspring is.

QUESTION: An enzyme is responsible for copying a DNA sequence into an RNA sequence.
A. Restriction enzyme
B. Reverse transcriptase.
C. RNA polymerase
D. DNA polymerase
EXPLANATION
RNA polymerase carries out the function to copy the DNA sequence into an RNA sequence. A restriction enzyme is used to cleave the DNA at the ends. Reverse transcriptase is used to synthesize DNA from RNA.DNA polymerase forms DNA strands by joining bases together.

QUESTION: The following picture is of ______ separated on the basis of their size and speed in it
A. Cloning
B. Recombinant DNA technique
C. Cell culture
D. Gel Electrophoresis
EXPLANATION
Gel electrophoresis is a technique used to separate DNA fragments according to their size and speed.DNA samples are loaded into wells (indentations) at one end of a gel, and an electric current is applied to pull them through the gel. DNA fragments are negatively charged, so they move towards the positive electrode.

QUESTION: When a plant cell receives a signal for death, it commits suicide by rupturing:
A. Nucleus
B. Cell membrane
C. Tonoplast
D. Chloroplast
EXPLANATION
The plant cell if it receives the signal to die, it commits suicide in a programmed way. This happens by the release of enzymes internally. All enzymes in plant cells are in a vacuole which is covered by a membrane called tonoplast. Rupturing of that membrane leads to the enzymes within vacuoles spilling out in the protoplasm.

QUESTION: Cell permeability and transport processes of Cell Membrane depend upon its ______ component.
A.  Phospholipid
B. Carbohydrates
C. Polysaccharide
D. Cellulose
EXPLANATION
The permeability of the cell membrane and its permeability depends upon the phospholipid content of that membrane. All other chemical components mentioned (carbohydrates, polysaccharides, and cellulose) are not part of the cell membrane.

QUESTION: Which disorder among the following CANNOT be detected by amniocentesis?..
A. Haemophilia
B. Heart defects
C. Tay-Sachs disease
D. Cystic fibrosis
EXPLANATION
This question is simply choosing the odd one out. Heart defects are not genetic. Amniocentesis is used to detect genetic defects like those mentioned in other options.

QUESTION: What is the phenomenon shown in the following picture?
A. Abscission
B. Senescence
C. Apical dominance
D. Ripening
EXPLANATION
As it can be seen in the diagram above the apical end is active and the lateral end is dormant. The apical bud is active, growing, and dominant as it can be seen growing far more than lateral buds. Therefore it can be said there is apical dominance in this plant. Option A is wrong because abscission is the natural detachment of parts of a plant, typically dead leaves and ripe fruit. Option B is wrong because of senescence, the condition or process of deterioration with age. Option D is wrong because ripening refers to the maturation of fruits.

QUESTION: In a laboratory, while working on a new species of fish, it is found that the fish has two varieties, red and brown. It was determined by another group of scientísts in another laboratory that brown is a dominant color in this species. If we have brown fish with us in the laboratory, how can we determine whether they are homozygous or heterozygous for the trait?
A.  Breed this fish with a redfish and check Fl generation
B.  Breed this fish with a redfish and check F2 generation
C.  Breed this fish with a brown fish and check Fl generation
D. Breed this fish with a brown fish and check F2 generation
EXPLANATION
To find out whether the given species is homozygous or heterozygous we should breed it with species having a recessive phenotype and check the first (F1) generation. If even one of the offsprings from the F1 generation have a recessive phenotype that means our species was heterozygous or else homozygous.

QUESTION: Which one is NOT true for coordination in animals?
A. Transmission by the nervous system is short-lived, whereas transmission by the hormonal system is long-lasting
B. The nervous system uses electrical impulses to send signals through neurons, whereas the hormonal coordination uses chemical messengers transported in the blood
C. Responses are often permanent in the hormonal system but temporary and reversible in the nervous system
D. In the nervous system secretory chemicals are released in blood while in the hormonal system; secretory chemicals are released in extracellular fluids
EXPLANATION
D statement is wrong because in the nervous system the secretory chemicals are not released in the blood they are released on another neuron, within a synapse. Whereas in the hormonal system secretory chemicals are released within the blood. All other statements are correct.

QUESTION: Plant pigments responsible for red, yellow, and orange colors in many fruits and vegetables are:
A. Chlorophyll A
B. Chlorophyll b
C. Carotenoids
D. Cellulose
EXPLANATION
Chlorophyll(a and b) Chlorophyll is blue-green. Chlorophyll b is green Carotenoids(xanthophyll and carotene) Xanthophyll is yellow. Carotene is red-orange

QUESTION: What does the following picture show?
A. Motor Neuron
B. Sensory neuron
C. Interneuron
D. Nerve
EXPLANATION
The diagram above is of sensory neurons. The cell body is not directly attached to the dendrites but through the dendron processes, this is what differentiates motor neurons from sensory neurons. It is not an interneuron because the interneuron has processes that are comparable to the size of the cell body which in this case aren’t. Option nerve is also wrong because the nerve is the collection of many neurons and this is just one neuron.

QUESTION: As a result of competition among friends, Ahmed eats a lot of pakoras, resulting in a rise of salts in the blood, to compensate______ triggered in the body.
A. Positive feedback
B. Negative feedback
C.  Internal feedback
D. External feedback
EXPLANATION
The compensatory effect is always carried out by a negative feedback mechanism only. Positive feedback reinforces the ongoing stimulus, not the compensation. Internal feedback and external feedback are not related to the physiology of the body.

QUESTION: Due to the presence of _____, the reabsorption of water is increased in the collecting ducts.
A. Mg
B. ADH
C. Kidney stones
D. High pH
EXPLANATION
The antidiuretic hormone helps to control blood pressure by acting on the kidneys and the blood vessels. Its most important role is to conserve the fluid volume of your body by reducing the amount of water passed out in the urine.

QUESTION: When a color-blind male marries a normal female, what will be the chances of colorblindness in his grandsons, if his daughter. married to a normal male?
A. 16%
B. 25%
C. 50%
D. 100%
EXPLANATION
Color Blindness is an X-linked recessive disorder. A man requires only one copy of defective genes to be colourblind. Whereas a woman requires two copies of defective genes to be colourblind. When a colourblind (XcY) man marries a normal woman (XX), all of their sons will be normal (XY) and all of their daughters will be carriers (XcX). Hence, in the next generation, all the children of all of their sons will be normal. There will be a nil probability of being colourblind. In the next generation of their daughter, all the daughters will be either normal or carrier. Whereas 50% of the sons will be colourblind acquiring defective genes (Xc) from their mother. Hence, considering the grandsons of both son and daughter, there are 25% chances or 0.25 probability of the grandson being colourblind. Thus, the correct answer is option B

QUESTION: Humans are _____ and mostly use ____ thermoregulation.
A. Ectotherm, behavioral
B. Endotherm. physiological.
C. Ectotherm. physiological
D.  Endotherm, behavioral
EXPLANATION
Endotherms generate most of the heat they need internally. When its cold out, they increase metabolic heat production to keep their body temperature constant. Because of this, the internal body temperature of an endotherm is more or less independent of the temperature of the environment.

QUESTION: Read the code mentioned in the following picture and arrange the sequence of all five codons in which Leucine is at 3rd position. while isoleucine is in 4th position. Keep in mind that CUU is the code for Leucine, AUU for Isoleucine and CAA or glutamine.
A. UAA-AUG-CAA-CUU-AUU
B. AUG-CAA-CUU-AUU-UAA
C.  AUU-AUG.CAA.CUU-UAA
D. AUG-UAA -CUU-AUU.CAA
EXPLANATION
Option B is most appropriate because it starts with a start codon and ends with a stop codon while having CUU and AUU at third and fourth positions respectively.

QUESTION: Because it is capable of dissolving more substances than any other liquid _______ is called the universal solvent.
A. Ethane
B. Alcohol
C. Chloroform
D. Water
EXPLANATION
Water is called the universal solvent because it is capable of dissolving more substances than any other liquid.

QUESTION: Which animals support Darwins view of inheritance of desirable variations?
A. Giraffe
B. Galapagos finches
C. Snake
D. All of the above
EXPLANATION
All of the above support Darwins view of inheritance which says that the desirable variations are more likely to sustain from generation to generation. Giraffes that had long necks as compared to those who had short necks were able to reach the food(leaves) on trees. In Galapagos finches, beaks changed as the birds developed different tastes for fruits, seeds, or insects picked from the ground or cacti. Long, pointed beaks made some of them more fit for picking seeds out of cactus fruits. Shorter, stouter beaks served best for eating seeds found on the ground.

QUESTION: Interphase is a phase of the cell cycle defined only by the absence of _______.
A. Enzymes
B. DNA
C. Replication
D. Cell division
EXPLANATION
Interphase is the phase of the cell cycle defined by the absence of cell division. The cell cycle involves two phases: interphase and cell division. Cell division itself involves many cell division phases(prophase,metaphase,anaphase,telophase etc).Thus we can say that Interphase is a cell cycle without cell division.

QUESTION: Juxta-medullary nephrons are present only in:
A. Fishes and amphibians
B. Amphibians and birds
C. Birds and mammals
D. Mammals and fishes
EXPLANATION
Juxtamedullary nephrons are found only in birds and mammals, and have a specific location: medullary refers to the renal medulla, while juxta (Latin: near) refers to the relative position of the renal corpuscle of this nephron - near the medulla, but still in the cortex.

QUESTION: What does a in the following picture show?
A. Cellular pathway
B. Symplast pathway
C. Apoplast pathway
D. Water pathway
EXPLANATION
Movement from cell to cell through plasmodesmata is a symplast pathway. Movement through the cell walls to the cell walls of other cells is called an apoplast pathway.

QUESTION: In semi-conservative replication, which of the following is true regarding the separation of two strands?
A. Primary structure is conserved, and secondary structure is disturbed
B. Secondary structure is conserved, and the primary structure is disrupted
C. both the primary and secondary structures are conserved
D. Both the primary and secondary structures are disrupted
EXPLANATION
In semi conservative replication, the original molecule is unzipped; each strand of the duplex becomes a part of another duplex. During the separation of two strands, the primary structure is conserved while the secondary structure is disrupted.

QUESTION: What is Molecule a in the following picture?
A. Host cell
B. Donor cell
C. Restriction enzyme
D. Recombinant DNA
EXPLANATION
When a piece of DNA from a host is cut out to be inserted into a source DNA to form a combined DNA it is called recombinant DNA.

QUESTION: A group of immune cells that mediates the cellular immune response by processing and presenting antigens for recognition of certain other cells or immune systems is called _______.
A. Natural killer cells
B. Interferons
C. Antigen-presenting cells
D. Vaccines
EXPLANATION
Antigen-presenting cells (APCs) phagocytose antigens and present those antigens on the surface of themselves so that they can be recognized by other cells of the immune system to generate an immune response.

QUESTION: Name the type of the following chromosome.
A. Metacentric
B. Submetacentric
C. Telocentric
D. Acrocentric
EXPLANATION
Option D is correct.

QUESTION: The complete aerobic oxidation of glucose results in the synthesis of as many ______ Molecules of ATP.
A. 16
B. 26
C. 36
D. 46
EXPLANATION
The complete aerobic oxidation of glucose results in the synthesis of as many as 36 molecules of ATP.

QUESTION: Primary function of fats in aquatic mammals is ________ and in terrestrial mammals is ________.
A.  to reserve water, to reserve salts
B.  to reserve salts, to reserve water
C. To reserve food, conserving heat
D. Conserving heat, to preserve food
EXPLANATION
Blubber is a thick layer of fat, also called adipose tissue, directly under the skin of all marine mammals. Blubber is an important part of a marine mammals anatomy. It stores energy, insulates heat, and increases buoyancy. In terrestrial mammals, the primary function of fats is to conserve as each gram of fat supplies the body with about 9 calories, which is quite efficient.

QUESTION: Crossing over is an exchange of genes between _______ resulting in a mixture of parental characteristics in offspring.
A. Sister Chromatids
B. Non-homologous Chromosomes
C.  Sex chromosomes
D. Homologous chromosomes
EXPLANATION
Crossing over is the exchange of genetic material between non-sister chromatids of homologous chromosomes during meiosis, which results in new allelic combinations in the daughter cells.

QUESTION: All of the following are reflex actions EXCEPT:
A. Change in the size of the pupil in response to light
B.  Swallowing of the bolus
C. Sudden jerky withdrawal of hand when pricked
D. Knees jerk in response to a blow
EXPLANATION
A reflex, or reflex action, is an involuntary and nearly instantaneous movement in response to a stimulus. Swallowing of the bolus is not an involuntary and instantaneous response rather a voluntary action.

QUESTION: What is in q2 Hardy Weinberg equilibrium?
A. Frequency of the dominant allele
B. Frequency of the recessive allele
C. Frequency of both alleles
D. Number of both alleles
EXPLANATION
p2+2pq+q2=0 represents the Hardy-Weinberg principle; where p is the dominant allele,q is the recessive allele.

QUESTION: The genome of viruses is composed of
A. DNA
B. RNA
C. Protien
D. Both A and B
EXPLANATION
Genomes of viruses can have both DNA and RNA. There are RNA viruses and DNA viruses that have RNA and DNA as genetic material in them. Proteins can not be the genome material.

QUESTION: Carbon dioxide fixation can be enhanced by enhancing the efficiency of:
A. Auxins
B.  Ribulose bisphosphate
C. Lactoferrin
D.  Agrobacterium
EXPLANATION
The carbon dioxide fixation process mainly involves the major enzyme called ribulose bisphosphate carboxylase-oxygenase, commonly known by the abbreviations RuBisCo, rubisco, RuBPCase, or RuBPco. By enhancing the efficiency of this enzyme can increase carbon dioxide fixation.

QUESTION: Label the following phenomenon
A. Exocytosis
B. Osmosis
C. Diffusion
D. Phagocytosis.
EXPLANATION
The diagram shows phagocytosis, which is the process by which a cell uses its plasma membrane to engulf a large particle, giving rise to an internal compartment called the phagosome. It is one type of endocytosis. Exocytosis is a form of active transport and bulk transport in which a cell transports molecules out of the cell. Osmosis is the movement of water molecules down the water potential gradient into or out of the cell. Diffusion is the movement of substances down the concentration gradient into or out of the cell.

QUESTION: Which of the following is NOT true for a gene?
A. A gene is a sequence of nucleotides in DNA.
B. A gene is the basic unit of heredity.
C. A gene codes for a molecule that has a function.
D. A gene expresses to form chromosomes.
EXPLANATION
All statements except D are correct. Genes do not express themselves to form chromosomes. Genes are small segments of DNA that join to form a whole chromosome.

QUESTION: The function of respiratory passage, Cilia is to keep the airways clear of:
A. Carbon dioxide
B. Oxygen
C. Dust
D. Carbon Monoxide
EXPLANATION
Goblet cells produce mucus that traps the dust particles; this mucus is then beaten by cilia. Cilia keeps airways clear of the dust particles by their constant ciliary movement. Cilia has no role to play in the removal of gases like oxygen, carbon dioxide, and carbon monoxide.

QUESTION:  _______ is the storage form of carbohydrate in animals and humans which is equivalent to the _____ in plants.
A. Glycogen, cellulose
B. Starch. cellulose.
C. Glycogen, starch
D. Starch, glycogen
EXPLANATION
Starch and glycogen are polysaccharides that are formed by joining many monosaccharides together by glycosidic bonds; this way they can store large amounts of energy this way. Glycogen is a storage form of carbohydrates in animals while starch in plants. Hence the answer is C. Cellulose is not a storage compound but just a structural carbohydrate.

QUESTION: As an essential element in living organisms, _______ ion is playing an important role in insulin secretion, the release of neurotransmitters, muscle contraction, and heartbeat regulation.
A. Sodium
B. Potassium
C. Calcium
D. Chloride
EXPLANATION
Calcium ion plays an important role in the secretion of neurotransmitters and insulin, as when calcium ion moves against the concentration gradient into the cells they stimulate microtubule elongation making the vesicles move towards the membrane and eventually expel exocytose out. Same ions can bind to Troponin molecules making them displace hydrophobic proteins such as troponin and tropomyosin to displace away.

QUESTION:  What are a and b in the following picture?
A. Allele and allele
B. Allele and gene
C. Gene and gene
D. Mutation and gene
EXPLANATION
These are alleles for purple and white flowers. It can be confused as genes sometimes which is wrong because here we can see the two forms of a gene(variations of a gene), so allele is the more appropriate word here.

QUESTION: Arrange the following according to the level of protein structures: a) lysozyme, b) haemoglobin, c) insulin, d) hairs.
A.  c, d, a, b
B.  a, b, c, d
C. d, c, b, a
D. a, d, c, b
EXPLANATION
C,D,A,B To reach this answer, you just need to use two of the facts. First, Insulin is a primary structure of protein hence should come first. Secondly, a well-known fact that hemoglobin is the quaternary structure of protein hence should come at the last. This happens only in option A.

QUESTION: In eggs, Ca+2 plays an important role especially at the time of fertilization. Therefore _______ are present in many thousand numbers inside the cell membrane.
A. Ribosomes
B. Chloroplast
C. Mitochondria
D. Endoplasmic Reticulum
EXPLANATION
It is known that the Endoplasmic reticulum acts as a reservoir for Ca2+ in cells as in contractile cells. Since Ca2+ plays an important role in fertilization therefore many Ca2+ in the form of the Endoplasmic reticulum should be present.

QUESTION: Genetic equilibrium is a:
A. Change of allele and gene frequency in a population
B. Stability of allele and gene quantity in a population
C. Change of allele and gene number in a population
D. Stability of allele and gene frequency in a population
EXPLANATION
Genetic equilibrium is the stability of a gene and its frequency in a population.

QUESTION: Choose the term from the following which is NOT a part of gene therapy?
A. Bone marrow transplant
B. Retrovirus
C. DNA Fingerprinting
D. Somatic cells
EXPLANATION
DNA Fingerprinting has nothing to do with gene therapy. Bone marrow transplants, retroviruses, and somatic cells are used to treat patients with mutations in genes. Bone marrow transplant replaces the stem cells in the bone marrow. Retroviruses are used to administer a gene into the cell so that it is incorporated into the DNA. Somatic cell gene therapy involves the placement of a human gene into a living persons somatic cells.

QUESTION: Synapse formed at the sites where the terminal branches of the axon of a motor neuron conduct a target muscle cell is called:
A. Sensory end plate
B. Synapse end plate
C. Motor end plate
D. Postsynaptic membrane
EXPLANATION
The site where terminal branches of the axon of a motor neuron form a synapse with the target muscle cell is called the motor end plate. The synapse end plate is a term that is not used.The sensory end plate is also a term that is also not known.The postsynaptic membrane is the term used for the membrane to which the neurotransmitters are released.

QUESTION:  Which of the following gases is used for welding purpose:
A. ethene
B. ethane
C. propane
D. ethyne
EXPLANATION
Ethyne is the third hottest natural chemical flame. It is supplied by the industrial gases industry for welding and cutting. Due to the high temperature of the flame, combustion of acetylene with oxygen produces a flame over 3600K. It is the hottest burning common fuel gas.

QUESTION: The chief ore of aluminium is:
A. Na3AlF6
B. Al2O3NH2O
C. Al2O3
D. Al2O3.H2O
EXPLANATION
The chief ore of aluminium is bauxite and its chemical formula is Al2O3.nH20 where n is the number of water molecules that keeps varying. Bauxite is a group of hydrated aluminium oxides from which pure aluminium can be extracted. It is known to be the main source of aluminium in the world.

QUESTION: Sp hybrid orbitals are formed by the mixing of:
A. One s and two p
B. One s and three p
C. One s and one p
D. Two s and two p
EXPLANATION
In sp hybridization, one s orbital and one p orbital hybridize to form two sp orbitals, each consisting of 50% s character and 50% p character. This type of hybridization is required whenever an atom is surrounded by two groups of electrons.

QUESTION:  Which one of the following bonds has the highest bond energy?
A. C-C
B. C ≡ C
C. N ≡ N
D. H-F
EXPLANATION
Triple bonds are stronger than single and double bonds, for understandable reasons. A nitrogen-nitrogen triple bond is stronger than a carbon-carbon triple bond because as we know that in the periodic table as we move from left to right the atomic sizes of elements decrease, this is due to the addition of electrons in the valence shell which increases nuclear charge. Carbon and nitrogen both elements are present in the same period but nitrogen (Z=7) is placed next to carbon (Z=6) thus it means the size of nitrogen is smaller than that of carbon and thus both the nitrogen atoms are much closer to each other unlike in case of carbon and hence more energy is required to break N-N triple bond compared to C-C triple bond.

QUESTION: Diamond is a bad conductor because it:
A. Has a tight structure
B. Has high density
C.  Has no free electron in the crystal
D. Is transparent to light
EXPLANATION
In diamonds, there are no free mobile electrons. Hence there wont be a flow of electrons, this is the reason why diamonds are bad conductors of electricity.

QUESTION: Ethers show the phenomenon of:
A. Position isomerism
B. Functional group isomerism
C. Metamerism
D. Cis-trans isomerism
EXPLANATION
Metamerism is a type of isomerism in which molecules have the same molecular formula but different alkyl groups around the functional group. For example, CH3-CH2-O-CH2-CH3 and CH3-O-CH2-CH2-CH3 are two metamers of each other.

QUESTION: The nature of positive rays depends on:
A. The nature of the electrode:
B. The nature of the discharge tube
C. The nature of the residual gas.
D. The shape of the electrode
EXPLANATION
The nature of positive rays produced in a vacuum discharge tube depends upon the nature of the residual gas-filled. The positive rays consist of positive ions obtained by removing one or more electrons from gas molecules.

QUESTION: The net heat change in a chemical reaction is the same whether it is brought about in two or more different ways in one or several steps. This is known as:
A. Henrys law
B.  Hesss law.
C. Joules principle
D. Daltons law
EXPLANATION
Hesss Law of Constant Heat Summation (or just Hesss Law) states that regardless of the multiple stages or steps of a reaction, the total enthalpy change for the reaction is the sum of all changes.

QUESTION:  The volume occupied by 1.4 g N2 at STP is:
A. 22.4 dm3
B. 1.12 dm3
C. 11.2 dm3.
D.  1.4 dm3
EXPLANATION
To find the moles of nitrogen, it is necessary to use the idea of molar volume Mass of N2 = 1.4 g Moles of N2 = 1.4g / 28g per mole = 0.05 moles One mole of N2 at S.T.P has volume = 22.414 dm3 0.05 moles of N2 at S.T.P has volume = 22.414 × 0.05 = 1.12 dm3

QUESTION: Metallic character of the elements:
A. decreases down the groups
B. increases down the groups
C. decreases across the periods
D.  increases across the periods
EXPLANATION
Both B and C are correct as the effective nuclear charge acting on the valence shell electrons increases across a period, the tendency to lose electrons will decrease. Down the group, the effective nuclear charge experienced by valence electrons decreases because the outermost electrons move further away from the nucleus. Therefore, these electrons can be lost easily. Hence, the metallic character decreases across a period and increases down a group.

QUESTION: The molarity of pure water is:
A. 1
B. 18
C. 36
D. 55.5
EXPLANATION
Molarity is defined as the number of moles of the solute per litre of solution. We know that the density of water is 1g/ml or 1 Kg/ L. Therefore, the mass of 1L of water is 1kg or 1000gm So now to find out the number of moles in the 1kg of water we can use the formula for mass to find out no. of moles in 1L(molarity). No.of moles=1000gm/18gm=55.56 mol 55.56 is thus the molarity of pure water.

QUESTION: The value of R (the gas constant) is
A. 0.0821dm3 atm k mol-1.
B.  803143 Nmk-Imole
C.  0.0821 dm3 atm k-I mol-1
D. 8.3143 dm3 atm-k-I mol
EXPLANATION
The value of R in dm3atm k-1mol-1 is 0.0821. The table below provides values of R in different units.

QUESTION: Tritium, an isotope of hydrogen contains:
A.  An equal number of electrons and neutrons
B. An equal number of electrons, protons and neutrons
C. The number of neutrons is double the number of protons
EXPLANATION
Tritium is the isotope of hydrogen having mass number 3 and proton number 1. A number of neutrons are mass number-number protons which turn out to be 2. So we can say that the number of neutrons is twice the number of protons.

QUESTION: Which statement about the following equilibrium is correct? 2SO2 (g) + O2(g) ⇌ 2SO3(g) ΔH= - 395 KJ/ mole
A.  The value of K falls, with a rise in temperature
B.  The value of Kp falls with an increase in pressure
C. The value of K is equal to Kp
D. The value of K remains constant with rise in temperature.
EXPLANATION
Kp equals the partial pressure of gases at the product side upon the partial pressure of gases at the reactant side. Increasing the temperature favours the reactant side as the backward reaction, in this case, is endothermic. The shift of equilibrium to reactant side causes the partial pressure of gases of reactant side to increase and pressure at product side to decrease. This in turn causes the value of Kp to fall.

QUESTION: The chemical name of K2[Zn(OH)4] is:
A. Potassium tetrahydroxyzinc (II)
B. Potassium tetrahydroxozincate (II)
C. Potassium tetrahydroxyzincate (VI)
D. Potassium hydroxyzinc (II)
EXPLANATION
First we note that the name of the counter ion is potassium now we write the name of the complex ion. It contains zinc(II), so it will be called as zincate(II). Note that we can determine the oxidation number of zinc by charge balance. Also it contains 4 OH− groups so it will be tetrahydroxo. Combining, we get that the name of the negative ion as tetrahydroxozincate(II) So, the name of the compound becomes Potassium tetrahydroxozincate(II). B is the correct answer.

QUESTION: When 3d orbital is complete, the next entering electron goes into:
A. 4f
B. 4s
C. 4p
D. 4d
EXPLANATION
When 3d orbital is complete the next entering electron goes into 4p level.  The order of increasing energies is 1s,2s,2p,3s,3p,4s,3d,4p,5s,4d,5p,6s.

QUESTION: Which of the following pair groups belong to meta directing Groups?
A. NH2 and -NO2
B. -OR and -OH
C. -NO2 and - SO3H
D. CI and -COOH
EXPLANATION
-NO2 and -SO3H are meta directing groups. The benzene ring has ortho positions(II and VI), para positions(IV), and meta positions(III and V). Those groups that are electrophile, also called meta-directing/deactivating groups, take electrons from the benzene ring towards themselves making the benzene to be deactivated. The benzene ring when deactivated directs the incoming groups to get attached to 3 and 5 positions which are meta positions.

QUESTION: What are the products of the below-mentioned equation? HNO3 +3HCI→
A. 2H2O + NOCI+Cl2
B. H2 + NOCI+ 2HOCI
C. H2O+ NOCI+ 2HCl
D. 2H2O+NOCI+ 2Cl
EXPLANATION
When HNO3 and HCl are mixed together in molar ratio 1:3 it forms aqua regia(royal water), which is 2H2O+NOCl+2Cl.The nascent chlorine released is responsible for dissolving metals like gold and platinum.

QUESTION: What is the order of the following reaction: 2NO +O2 -> 2NO2
A. 0
B. 1
C. 2
D. 3
EXPLANATION
The order of the reaction is not decided by adding moles in the equation on the reactant side but by adding the exponents on these reactants in the rate equation. However, in this case, since the rate equation is not given we are not left with any choice rather than just adding moles on the reactant side of the equation which is 2+1=3.

QUESTION: One Calorie is equivalent to:
A. 0.4184J
B. 41.84 J
C.  4.184 J
D. 418.4 J
EXPLANATION
One Calorie is equivalent to 4.184 J.

QUESTION: Paramagnetic elements contain:
A. All paired electrons
B. All unpaired electrons
C. Few unpaired electrons.
D. Unequal electrons and protons
EXPLANATION
A paramagnetic element is one that has paramagnetic electrons(few unpaired electrons). A paramagnetic electron is an unpaired electron. An atom is considered paramagnetic if even one orbital has a net spin. The unpaired electrons of paramagnetic atoms realign in response to external magnetic fields and are therefore attracted.

QUESTION:  How many atmospheres correspond to 1050 torr?
A. 1.050
B. 10.38
C. 1.380
D.  2.760
EXPLANATION
In ancient times, the Torr was defined as a millimetre of Hg. So, as 1 atm = 760 mm Hg, therefore, 1 atm is also considered to be equal to 760 torrs. Now, we can calculate the atmospheres corresponding to 1050 torr, ∴ 1050 torr = 1050/760 atm = 1.38 atm

QUESTION: The mass of an electron is:
A. 1.008 amu
B. 1.009 amu
C.  0.000550 amu
D. 0.5500 amu
EXPLANATION
The mass of an electron is 0.000550 amu amu=atomic mass unit The mass of the neutron is 1.009amu and the mass of the proton is 1.008 amu.

QUESTION: The rate of E1 reaction depends upon:
A. The concentration of the substrate
B.  The concentration of the nucleophile
C. The concenıration of the nucleophile and the substrate
D. The amount of the solvent used
EXPLANATION
An E1 reaction is a Unimolecular Elimination reaction. This means the only rate-determining step is that of the dissociation of the leaving group from the substrate (Hence option A is correct). E2 is bimolecular, in which nucleophilic attack is also a part of the rate-determining step.

QUESTION: The number of bonds in nitrogen molecules are:
A. One sigma and one pi
B. One sigma and two pi
C. Three sigma only
D. Two sigma and one pi
EXPLANATION
The nitrogen molecule has three bonds in total that are 1 sigma and 2 pi. A single bond is always 1 sigma A double bond is always 1 sigma and 1 pi A triple bond is always 1 sigma and 2 pi.

QUESTION: An ionic compound A+ B- is most likely to be formed when:
A. The ionization energy of A is high and the electron affinity of B is low.
B. The ionization energy of A is low and the electron affinity of B is high.
C. The ionization energy of A and the electron affinity of B is high.
D. The ionization energy of A and the electron affinity of B is low.
EXPLANATION
The ionization energy (IE) is defined as the amount of energy required to remove the most loosely bound electron of an isolated gaseous atom to form a cation. Electron affinity of an atom or molecule is defined as the amount of energy released when an electron is added to a neutral atom or molecule in the gaseous state to form a negative ion. When the ionization energy is low and electron affinity is high, more will be the tendency to form an ionic bond.

QUESTION:  The electrophile in aromatic sulfonation is:
A.  H2SO4
B. HSO4
C. SO3H+
D. SO3
EXPLANATION
SO3H+ is the electrophile in the sulfonation of benzene. SO3 can also be considered as an electrophile for this reaction but since SO3 is not alone able to sulfonate benzene, but requires concentrated sulfuric acid to attack the benzene so SO3H+ is the more appropriate option.

QUESTION: Choose the correct IUPAC name for the following complex. [Cr(NH3)4Cl2]Cl
A. Trichlorotetra amine chromium (lII)
B. Dichlorotetra amine chromium (III) chloride
C. Dichloro Tetra ammonia chromium (III) chloride
D. Dichlorotetra amine chromate (lll) chloride
EXPLANATION
Option B is the correct option because it abides by IUPAC rules of naming complex ions. Option A is wrong because it says “Trichloro” when originally we have TWO chlorine atoms, not THREE. Option C is wrong because it says “ammonia” when according to rules NH3 should be called amine when in complex ions. Option D is wrong because it says “chromate”, the correct way to refer to Cr here is Chromium (III) instead.

QUESTION: SN2 reactions can be best carried out with:
A. Primary alkyl halides
B. Secondary alkyl halides
C.  Tertiary alkyl halides
D.  Both primary and tertiary alkyl halides
EXPLANATION
The SN2 reaction is most favored by primary alkyl Halides(1∘). This is because the primary alkyl halide provides minimum hindrance for SN2 substitution reaction. The order of reactivity of alkyl halide towards SN2 can be given as follow: 1∘>2∘>3∘.

QUESTION:  Name the main product formed as a result of the following reaction H3C - (CH2)5 - CH3 ————> Product          n-heptane Conditions: 480 - 550 C, 150 - 399 psi V2O5
A. Benzene
B. Toluene
C. Xylene
D. Cyclohexane
EXPLANATION
The above reaction leads to cyclization of n-heptane followed by the aromatization of that cyclic ring, this forms toluene, option B is correct. Benzene is the wrong option because benzene has six carbon while n-heptane has 7 carbon atoms. Cyclohexane is also the wrong option for the same reason. Xylene has 8 carbon atoms while our reactant has 7 carbon atoms.

QUESTION: The pH of 10-3 mol dm-3 of an aqueous solution H2SO4 is:
A. 3.0
B. 2.7
C. 2.0
D. 1.5
EXPLANATION
Correct option is 2.7.

QUESTION:  The oxidation state of Cl in HClO4 is:
A. -1
B. +5
C. +7
D. -7
EXPLANATION
The overall oxidation state of this compound is 0. The oxidation state of hydrogen ion is +1, the oxidation state of one oxide ion is -2.  So: +1+x+4(-2)=0 +1+x-8=0 x=8-1=+7 Hence C.

QUESTION:  In a zero-order reaction, the rate is independent of:
A. The temperature of the reaction
B.  The concentration of reactants.
C. Concentration of products
D. Catalyst used
EXPLANATION
Unlike the other orders of reaction, a zero-order reaction has a rate that is independent of the concentration of the reactant(s). As such, increasing or decreasing the concentration of the reacting species will not speed up or slow down the reaction rate.

QUESTION: Which one of the following is NOT a nucleophile?
A.  H2S
B. BF3
C. NH3
D. CN-
EXPLANATION
BF3 is not a nucleophile but an electrophile. Electrophiles are the positively charged or electron-deficient species that get attracted towards negative charge or electron pairs. They are also the ones who readily accept an electron pair. Now if you want to accept electron pairs you must have at least one empty orbital to accept those lone pairs. If you check the hybridization of BF3 it would come out to be Sp2. It still leaves BF3 with one empty P orbital. BF3 uses this empty orbital to accept an electron pair and therefore acts as an electrophile. Electrophiles are also called the lewis Acid

QUESTION: Which of the following molecules have zero dipole moments?
A. NH3
B. CHCl3
C. H2O
D. BF3
EXPLANATION
Only in BF3 do the dipole moments of the bonds cancel out as shown below: In other molecules, the dipoles do not cancel out like this.

QUESTION: The ligand field effect splits five degenerate d-orbitals into two sets with different energies, the pair of high energy degenerate orbitals is:
A. dxy, dyz
B. dyz, dzx
C. dx2 ,d
D. dx2 - y2, dy2
EXPLANATION
The ligand field splits the five d-orbitals into two states: eg and t2g.eg being a higher energy state and t2g being the lower energy state. This demonstrated by the diagram below:

QUESTION: A catalyst increases the rate of reaction by:
A. decreasing the activation energy
B.  decreasing the concentration of reactants
C.  decreasing the temperature
D. increasing the temperature
EXPLANATION
A catalyst speeds up a chemical reaction, without being consumed by the reaction. It increases the reaction rate by lowering the activation energy for a reaction, hence option A is correct.

QUESTION: Which of the following ions has the largest heat of hydration?
A. Na+
B. Al3+
C. F-
D. Sr2+
EXPLANATION
Hydration energy depends upon size of cation and charge of cation so higher the charge of cation and lower the size of cation have higher hydration energy. So, here Al+3 will have highest hydration due to smaller size and charge.

QUESTION: Determine the significant figures in 0.0085:
A. 4
B. 3
C. 2
D. 1
EXPLANATION
For example, 0.008 has only one significant figure and 0.0085 has two significant figures. Zeros between non-zero digits are significant. For example, 3.05 has three significant figures.

QUESTION: Write the chemical name of the given structure.
A. 4-ethy1-25-hexadiyne
B. 3-ethyl-1,4-hexadiene
C.  3-ethyl-1,4-hexadiyne
D.  3.ethyl-2,5-hexadiyne
EXPLANATION
The numbering of carbon atoms in this organic compound is from right to left because the ethyl group is attached nearer the right side than the left. An ethyl group is attached to the third carbon so the IUPAC name should be “3-ethyl”.Now, as it can be seen the triple bond can be formed between 1st and 2nd carbon, and 4th and 5th carbon, so it should be “1,4-hexadiyne”. Option C satisfies all of these rules. All other options, one way or another, don’t abide by these rules.

QUESTION: Copper (Cu, z=29) is a
A. d1 system with respect to the electronic configuration
B. d3 system with respect to THE electronic configuration
C. d7 system with respect to the electronic configuration
D. d10 system with respect to the electronic configuration
EXPLANATION
The electronic configuration of Cu (Copper Z=29) is 1s2, 2s2, 2p6, 3s2, 3p6, 3d10, 4s1, as it can be seen in an electronic configuration that the 3d orbital of Cu has 10 electrons so it can be said that Cu belongs to the d10 system.

QUESTION: The carbon number of gasoline is:
A. C5 - C6
B. C6 - C7
C. C5 - C10
D. C12 - C15
EXPLANATION
The hydrocarbons of gasoline contain typically C5-C10 carbon atoms.

QUESTION: The oxidation number of Br in Br2 is:
A. -1
B. -2
C. 0
D. +1
EXPLANATION
By definition, the oxidation state of all elements in their natural state is 0. Br2 is the natural state for bromine so, its valence (oxidation state) is 0.

QUESTION: The number of moles of CO2 which contain 8.0 g of oxygen is:
A. 0.25
B. 0.50
C. 0.75
D. 1.00
EXPLANATION
Mass of Oxygen = 8 g The molar mass of Oxygen =32g mol ⁻¹ Number of moles of Oxygen = 8 / 32 moles                                               = 0.25 moles 1 mole of CO₂ will contain 1 mole of Oxygen ∴ 0.25 mole of oxygen is present in 0.25 moles of CO₂

QUESTION: Hydrogen bonds are represented by:
A. dative bonds
B. full bond
C. partial charges
D. dotted bonds
EXPLANATION
Hydrogen bonds are represented as H···Y system, where the dots represent the hydrogen bond.

QUESTION: Effusion of gases take place through a hole with:
A.  Hole dimensions
B.  Infinite dimensions
C. Slit like dimensions
D. Molecular dimensions:
EXPLANATION
Effusion of gases takes place through a hole that has molecular dimensions. Slit for the effusion of a gas is so small that it allows even a single molecule to pass, so for that our slits should have “molecular” dimensions.

QUESTION: For an equilibrium change involving gaseous phase, the forward reaction is first order while the reverse reaction is second order. The unit of Kp for the forward equilibrium is:
A. atm
B. atm2
C. atm-1
D. atm-2
EXPLANATION
The correct option is A as the question asks for the Kp for the forward reaction.

QUESTION: In t-butyl alcohol, the tertiary carbon is bonded to:
A. No H-atoms
B. One H-atoms
C. Three H-atoms
D. Four C-atoms
EXPLANATION
Tertiary alcohol has the hydroxyl group on a tertiary (3°) carbon atom, which is bonded to three other carbons.  A primary alcohol has the hydroxyl group on a tertiary (1°) carbon atom, which is bonded to one other carbon. Secondary alcohol has the hydroxyl group on a secondary (2°) carbon atom, which is bonded to two other carbons.

QUESTION: The oxidation potential standard hydrogen electrode is arbitrarily taken as:
A. -0.76 volts
B. 0.00 vols
C. +1.5 volts
D. 1.0 vots
EXPLANATION
Hydrogen has an oxidation potential of 0.

QUESTION: Down’s cell is used to prepare:
A. Sodium carbonate
B. Sodium bicarbonate
C. Sodium hydroxide
D. Sodium metal
EXPLANATION
Downs cell sodium is prepared by electrolysis of molten (fused) sodium chloride. Some CaCl2 is added to lower the melting point of NaCl from 801 ℃ to 600 ℃. The cell consists of an iron vessel. A large block of graphite acts as an anode.

QUESTION: Which of the hydrogen compounds has the highest percentage of ionic character?
A. HCI
B. HBr
C. HI
D. HF
EXPLANATION
HF has the highest percentage of ionic character because F has the greatest electronegativity. F, Cl, I, and Br are all in the same group so that means their electronegativity (and thus the percentage of ionic character) decreases as they go down the group in the periodic table.

QUESTION: The solubility product of AgCl is 2.0x10-10 mol-2 dm-6. The maximum concentration of Ag-1 ions in the solution is:
A. 2.0x10-12 mol dm-3
B. 1.14 x 10-5 mol dm-3
C. 1.0x10-12 mol dm-3
D. 2.5x10-10 mol dm-3
EXPLANATION
Let ‘X be the concentration of Ag+2. Solubility product=2.0x10-10 mol2 dm-6 [AgCl-2]=[Ag2+][Cl-1] 2.0*10-10=x*x 2.0*10-10=x2 x=c

QUESTION:  A limiting reactant is the one, which:
A. is taken in lesser quantity in grams as compared to the other reactant
B. is taken in lesser quantity in volume as compared to the other reactant
C.  gives the minimum amount of the product which is required
D. gives equal amounts of the reactants and products
EXPLANATION
The reactant in a chemical reaction limits the amount of product that can be formed. The reaction will stop when all of the limiting reactants are consumed.

QUESTION: The chemical formula of Tincal is:
A. Na2B2O7.10H2O
B. Na2B4O7 . H2O
C. Na2B4O7 . 10 H2O
D.  Na2B2O5 . 10 H2O
EXPLANATION
The chemical formula of Tincal is Na2B4O7 10H2O This requires just a factual recall.

QUESTION: Hydrogen resembles the elements of groups:
A.  I-A, V-A and VIll-A
B.  I-A, IV A and Vl-A
C. I-A, II-A and VIl-A
D.  I-A, IV-A and VIl-A
EXPLANATION
Hydrogen resembles the elements from the groups I-A, IV-A, and VIII-A. It is because hydrogen has one electron in its outermost orbit. It shares the chemical properties of a group I element as it can lose that electron to form a cation. It has a half-filled outermost orbit like group IV-A as the total capacity of the outermost orbit is 2. It can gain one electron to fill its outermost orbit like group VII-A elements.

QUESTION:  The unit cell parameters of the monoclinic system are:
A.  a = b ≠ c ; α=β=γ=90
B. a ≠ b ≠ c ; α=γ=90 ; β≠90
C. a ≠ b = c ; α=β=90; γ≠90
D.  a = b = c ; α=β=γ=90
EXPLANATION
According to the crystal systems in the table given below, option B is correct.

QUESTION: The colour of transition metal complexes is due to:
A. d-d transition of electrons.
B. Paramagnetic nature of transition elements
C. Loss of s-electrons
D. Refraction phenomenon
EXPLANATION
The striking colours exhibited by transition-metal complexes are caused by the excitation of an electron from a lower-energy d orbital to a higher energy d orbital, which is called a d–d transition. During this phenomenon some specific wavelengths are absorbed while some get reflected, giving the metal ion the colour.

QUESTION: Orbitals having the same energy are called:
A. Hybrid orbitals
B.  Degenerate orbitals
C. valence orbitals alence orbitals
D.  Sub-orbitals
EXPLANATION
Degenerate orbitals are the orbitals of the same subshell having equal energies. When the electrons of the orbitals are not influenced by any external factors like an electric field or magnetic field, they have the same energies.

QUESTION: The oxidation state of Cl in HClO4 is:
A. -1
B. -5
C. +7
D. -7
EXPLANATION
The overall oxidation state of this compound is 0. The oxidation state of hydrogen ion is +1, the oxidation state of one oxide ion is -2. So: +1+x+4(-2)=0 +1+x-8=0 x=8-1=+7 Hence C.

QUESTION: The pH of 10-3 M H2SO4 solution is:
A. 3.0
B. 2.7
C. 2.0
D. 1.5
EXPLANATION
Since the concentration of H2SO4 is 10-3 (M), the concentration of H+ in the solution will be 2 x 10-3(M) (because each molecule of H2SO4 releases 2 H+ ions). pH of a solution is -log([H+]). where, [H+] is the concentration of H+ in the solution. So, the pH of the given solution is, -log(0.002)=2.69. Therefore the pH of the given solution is 2.69.

QUESTION: In the Compton Scattering experiment the X-ray wavelength change Δλ is ___________. Here h is Planck constant, m rest mass of electron and θ is angle after scattering.
A. Δλ=h/moC(1+ Cosθ)
B. λ=h/moC(1 - Cos2θ)
C. Δλ=h/moC(1 - Cosθ)
D. Δλ=h/moC2(1 + Cosθ)
EXPLANATION
Option C is correct. The derivation is given below:

QUESTION:  An object is falling down with a speed of 20 m/s. After 3 seconds its velocity will be ______ m/s (g = 10 m/s2).
A. 05
B. 50
C. 55
D. 95
EXPLANATION
v=u+at v=20+10(3) v=20+30=50 m/s. Hence B.

QUESTION:  In Youngs double-slit experiment, if d is the separation between two slits 1 is the wavelength of light and θ is the angle of the line from the centre of slits to the point of observation on the screen; then for maxima (bright fringe); the formula is _________.
A. 2d sinθ = mλ ; m = 0 .. 2, …
B.  dsinθ = mλ ; m = 0, 1, 2, ...
C. .sin θ = (m + ½) λ ; m = 0, 1, 2, …..
D.  2msinθ = dλ ; m = 0, 1, 2, ….
EXPLANATION
The formula to determine the angle between maxima (bright fringe) to the centre of the line is dsinθ = mλ.

QUESTION: The polarization of light by tourmaline crystals is due to the ______effect.
A. selective diffraction
B. selective reflection
C. selective interference
D. selective absorption
EXPLANATION
Polarized light can also be produced by using a tourmaline crystal. Tourmaline (a double-refracting substance) removes one of the polarized rays by selective absorption. Organic substances that affect polarized light that passes through their solution are called optically active.

QUESTION: A paratrooper is falling down with uniform velocity and also rotating with a constant angular velocity of 0.2 rad/sec. The body satisfies ______.
A. The first condition of equilibrium but not second
B. Second condition of equilibrium but not first
C.  The first and second conditions of equilibrium
D. Neither the first nor the second condition of equilibrium
EXPLANATION
Body satisfies the first and second law of equilibrium. The first law states that for an object to be in equilibrium forces acting on it must be equal and opposite, since the paratrooper is falling with a uniform velocity, this means this is true. The angular velocity is also constant, which implies that torque acting on the paratrooper clockwise is equal to the torque acting anticlockwise.

QUESTION:  If 92 U 235, decays by emitting two α one β and two γ -rays the new daughter element is = _______.
A. 88 Y 227
B. 89 Y 227
C. 90 Y 227
D. 89 Y 231
EXPLANATION
During beta decay, a neutron decays to form a proton that makes a 93 U 235. During alpha decay, 2 protons and 2 neutrons are released from the element. Since there are two alpha decays, that means the total loss in mass number would be 8 and in proton number would be 4, making 93 U235 convert to 89 U227. Gamma decay causes no effect on nucleons. Hence our answer is B.

QUESTION: A changing current in a coil sets up a changing magnetic field around it which in turn induces an e.m.f. in it. This effect is known as _______
A. Simple induction
B. Mutual induction
C. Self-induction
D. EMF induction
EXPLANATION
The property of induction of e.m.f. in the same coil when there is a change in current in it is called self-induction. Hence, the answer is option B.

QUESTION: The principle of an AC generator is.
A. Lenzs law
B. Faradays Law
C. Self-induction
D. Amperes law
EXPLANATION
It works on the principle of Faraday’s law of electromagnetic induction. Whenever a coil is rotated in a uniform magnetic field about an axis perpendicular to the field, the magnetic flux linked with the coil changes, and an induced emf is set up across its ends.

QUESTION: Braggs Law for measurement of wavelength à. of i-rays, using crystal lattice planes having distance d between each other, for constructive interference for integral multiple of i is.
A. mλ = 2d/ sinθ
B. 2λ =md sinθ
C.  mλ = 2d sinθ
D. dλ = 2m sinθ
EXPLANATION
nλ=2d⋅sin⁡θ where • n is an integer determined by the order given, • λ is the wavelength of x-rays, and moving electrons, protons, and neutrons, • d is the spacing between the planes in the atomic lattice, and • θ is the angle between the incident ray and the scattering planes.

QUESTION: The velocity of a particle is related to time according to the equation V= ct3. The dimensions of constant are _______.
A. L-1 T-1
B. L T-3
C. LT -4
D. L-2 T-2
EXPLANATION
For the principle of homogeneity; V=ct3 (LT-1)=c(T3) c=LT-1/T3 c=LT -1-3 c=LT -4.

QUESTION: What should the distance of an object from a convex lens of focal length f=10 cm in order to produce an erect image twice as large as the object?
A.  20 cm from the lens
B. 15 cm from the lens
C. 10 cm from the lens
D. 05 cm from the lens
EXPLANATION
See the image attached. However, the answer can also be reached without doing any calculation at all. Heres how: The lens in question is a convex lens. We know that for a convex lens to form a virtual, magnified image, the object must be placed within the focal length of the lens. This means that the object distance should be less than the focal length. Only option D satisfies this condition.

QUESTION: A material that does NOT become radioactive after absorbing neutrons is called.
A. Shielding
B. Reactor fuel
C. Control material
D. Coolant
EXPLANATION
Those materials that do not become radioactive after absorbing neutrons are called radioactive shielding materials.

QUESTION: The scalar or Dot product of Vectors (3i - 2j + 4k) and (2i + 2j - 3k) is _____.
A. -9
B. -10
C. -11
D. 10
EXPLANATION
(3)(2)+(-2)(2)+(4)(-3) 6-4-12 =-10

QUESTION: The sum of Kinetic energy and the Potential energy is always constant to provide _____ .
A. There is a greater force of friction involved during motion
B. The body is in simple harmonic motion
C. There is less force of friction involved during motion
D. No force of friction involved during motion
EXPLANATION
The law of conservation of energy states that energy can neither be created nor destroyed. Therefore, the total energy in simple harmonic motion will always be constant. However, kinetic energy and potential energy are interchangeable. Given below is the graph of kinetic and potential energy vs instantaneous displacement.The graph for a body is SHM.

QUESTION: Three times decrease in the distance between the plates of a parallel plate capacitor will _______.
A. Decrease the capacitance three times
B. Decrease the capacitance nine times
C. Increase the capacitance three times
D. Increase the capacitance six times
EXPLANATION
The generalized equation for the capacitance of a parallel plate capacitor is given as C = ε(A/d) where ε represents the absolute permittivity of the dielectric material being used. The dielectric constant, εo also known as the “permittivity of free space” has the value of the constant 8.84 x 10-12 Farads per meter. Conductive plate area is symbolized by “A” and distance by d. As it can be seen C and d are inversely proportional to each other, three times decrease in distance and increase capacitance three times.

QUESTION: A car of mass 1200 kg initially at rest has been accelerated to a speed of 8 m/s in 16 meters. Average acceleration of the car is ______ m/s2? And force is _____ N?
A. 1.5 and 1500
B. 2.5 and 2400
C. 3.5 and 3500
D. 2 and 2400
EXPLANATION
m=1200kg v=8m/s d=16m v2=u2+2as (8)2=(0)2+2(a)(16) 64=32a a=2m/s2 F = ma = 1200×2 =2400N

QUESTION: In the SI system of units, the fundamental units of length, mass, and time are ____, _____ and respectively:
A. Meter Kilogram and Kilo second
B. A kilometre, Kilogram and hour
C. Meter, Kilogram, and Second
D. Centimetre, Centigram and Second
EXPLANATION
The fundamental units of length, mass, and time are meters, kilogram, and seconds.

QUESTION: In Nuclear Physics the mass defect is referred to _______.
A. The difference in masses of free neutrons and protons.
B. The difference in masses of free neutrons and bonded nucleus
C. The difference in masses of free nuclear constituent and bonded nucleus
D. Difference between atomic mass and atomic number
EXPLANATION
When nuclear constituents are free they have a higher mass but when they get bounded in the form of a nucleus their overall mass decreases. This happens because of the conversion of some mass into energy (which is lost), this loss in mass is termed as mass defect.

QUESTION:  The formula for the Paschen series for the Hydrogen spectrum is _______.
A. 1/λ=Rh(1/22 - 1/n2 ) n=3,4,5
B. 1/λ=Rh(1/42 - 1/n2 ) n=2,3,4,5
C. 1/λ=Rh(1/42 - 1/n2 ) n=5,6,7
D. 1/λ=Rh(1/32 - 1/n2 ) n=4,5,6
EXPLANATION
The formula for the Paschen series is option D, this is a factual recall.

QUESTION: The necessary condition for Boyles law to hold is that the process must be ______.
A. Isobaric
B. Adiabatic
C. Isochoric
D. Isothermal
EXPLANATION
The necessary condition for Boyles law is that the process should be isothermal. Pressure and volume are said to be inversely proportional only when the temperature is kept constant.

QUESTION: A body is hanging from a rigid support by an extensible string of length L. It is struck inelastically by an identical body of mass m with horizontal velocity v =√2gl , the tension in the string increases just after striking by:
A. mg
B. 3mg
C. 2mg
D. None of these
EXPLANATION
Correct option is C.

QUESTION: When an object is thrown upward, it rises to height h. How high is the object in terms of h, when it has lost ⅓ of its original kinetic energy?:
A. H/2
B. H/3
C. H/4
D. H/6
EXPLANATION
If an object loses its kinetic energy by 1/3rd that means this energy is converted into its potential energy, as according to the law of conservation of mass loss in kinetic energy is equal to gain in potential energy. KE=PE A decrease in KE of ⅓ means an increase in PE by 1/3rd 1/3KE=PE+1/3PE Thus, to gain 1/3rd of that kinetic energy the object must climb 1/3rd of its height Link to further discussion: https://www.quora.com/When-an-object-is-thrown-upward-it-rises-to-height-h-How-high-is-the-object-in-terms-of-h-How-high-has-it-lost-1-3-of-its-original-kinetic-energy

QUESTION: The internal energy of the system decreases in an adiabatic process. Which of the following must be true regarding this process?
A. Heat flows out of the system
B. Work is done by the system
C. Work is done by the surrounding
D. The potential energy of the system is changing
EXPLANATION
Refer to the following solution:

QUESTION:  If μ is the permeability of the medium and ∈ permittivity of the medium then the value of √ 1 / μ . ∈. Is equal to ______.
A. Plancks constant
B. Speed of sound waves
C. Speed of ultrasound waves
D. Speed of light
EXPLANATION
√ 1 / μ . ∈ would represent the speed of light.

QUESTION: Which statement describes the electric potential difference between two points in the electric field of charge Q?
A. The difference of electric field between the points per unit charge.
B. The ratio of the power dissipated between the points to the mass of charge
C. The work done in moving a test charge between points divided by the magnitude of the test charge.
D. The force required to move a unit positive charge between the points per unit charge.
EXPLANATION
This question is simply revising how the electric potential is defined as it is work done per unit charge in moving that charge from one place to the other in the electric field. All others are not the definitions of electric potential.

QUESTION: In a step up transformer ________.
A. Vs > Vp while Is > Ip
B. Vs < Vp while Is > Ip
C. Vs = Vp while Is > Ip
D. Vs > Vp while Is < Ip
EXPLANATION
Step-up transformers increase the voltage and decrease the current.

QUESTION: If a compressible medium has bulk modulus denoted by B and density denoted by P, then a Newtons formula for the speed of sound in a medium is _____.
A. V = √ B / p
B. V = √ B p
C. V = B / p
D. V = √ p / B
EXPLANATION
This is also just a factual recall: V = √ B / p

QUESTION: In order to produce pair production the minimum energy of photon required is:
A. 1.02 KeV
B. 1.02 MeV
C. 10.2 KeV
D. 1.00 MeV
EXPLANATION
A factual recall to which the answer is 1.02 MeV

QUESTION: The Bohr’s postulate for stationary orbits of Hydrogen atoms _____. Here m is the mass of the electron, v velocity, r orbital, and h is Plancks constant.
A. mr=nhv/2ℼ
B. mvr=nh/2ℼ
C. mvr=nh/2ℼr
D. mv=nhr/2ℼ
EXPLANATION
Bohr’s equation for a stationary object is mvr=nh/2ℼ

QUESTION:  A car starts from rest and moves with constant acceleration. During the 4th second of its motion, it covers a distance of 21 meters. The acceleration of the car is _____ m.
A. 04
B. 06
C. 08
D. 16
EXPLANATION
refer to the following:

QUESTION: Which particle (marked A) is obtained in the following nuclear reaction? 4Be9 + 2He4 -> 6C12 + A
A. A = 1H1
B. A = 1n0
C. A = 1H2
D. A = 2He2
EXPLANATION
To see which particle is obtained in the nuclear reaction, we should see both sides of the equation and check which particle should fit in the nuclear reaction to balance out the equation. In this case, since the mass number is only less on the product side and not the proton number that means neutrons should be on the product side.

QUESTION: An electron moving with velocity v has momentum 3 x 10 -26 Kg.m/s. The de Broglie wavelength associated with it is ______. Value of h = 6.63 x 10-34 is.
A. 24.1 nm
B. 22.14 m
C. 22.1 nm
D. 22.1 mm
EXPLANATION
λ=h/p ; p=momentum λ=6.63 x10-34/3x10-26 λ=22.1x10-9 m λ=22.1 nm.

QUESTION: Laplaces correction to Newton’s formula is based on the fact that the compressions and rarefactions occur as ______.
A. Adiabatic process
B. Isothermal process
C. Isochoric process
D. Isobaric process
EXPLANATION
Newton assumed that the pressure–volume changes that occur when a sound wave travels through the gas are isothermal. Laplace was subsequently able to obtain agreement between theory and experiment by assuming that pressure–volume changes are adiabatic.

QUESTION: A car 500 kg is travelling at a constant speed of 9 m/s round a curve of 100m. What is the centripetal force?
A. 205N
B. 305N
C. 405N
D. 505N
EXPLANATION
F = Mv2 / R F = 500× 9×9 / 100 F = 405 N

QUESTION: When a train whistling passes near you, a considerable change in the pitch of the sound is heard. When the train is moving away, the pitch of the sound _____ whereas the pitch of the sound _____ when the train is approaching.
A. Increases … decreases
B. Increases … remains same
C. Decreases … increases
D. Decreases … remains same
EXPLANATION
When the train is moving away the pitch of the sound decreases and when the train moves towards you the pitch of the sound increases.

QUESTION: The vector product of two vectors A and B is ____ vectors A and B.
A. Equal to the product of magnitudes of
B. In the plane parallel to
C. Perpendicular to the plane containing
D. Less in magnitude than the product of magnitudes of
EXPLANATION
The product of two vectors is perpendicular to the plane containing the two vectors

QUESTION: If a conductor carrying current I is placed in uniform magnetic field B, It experiences a magnetic force F. The direction of this force F.
A. + is parallel to current I only
B. Is perpendicular to current I only
C. Is perpendicular to magnetic field B only
D. Is perpendicular to both current I and magnetic field B
EXPLANATION
The direction of the force F is perpendicular to the current I and the field B, when in a magnetic field.

QUESTION: A battery of 12 volts is connected to three resistors of 4 Ohm, 5 Ohm and 3 Ohm joined together in parallel. The current through the 3 - Ohm resistances is _____.
A. 1.0A
B. 2.5A
C. 3.0A
D. 4.0A
EXPLANATION
Since the voltage is constant in all the resistors. Then the voltage across the 3 Ohm resistor will be 12 volts too. Resistance of it is 3 Ohm. We can apply: V=IR (12)=I(3) I=4A.

QUESTION: If the time interval between the occurrence of two events is measured in a frame with no relative motion in which two events occur. Then the time measured by the observer in a frame moving with relative velocity v is _______.
A. Option A
EXPLANATION
t = t0/(1-v2/c2)½    Is the formula used in the equation. This is just a factual recall.

QUESTION: A travelling wave, in which the particles of the distributed medium, move parallel to the direction of propagation of the wave is called:
A. Transverse wave
B. Circular wave
C. Longitudinal wave
D. Stationary wave
EXPLANATION
A longitudinal wave is a wave in which particles of the medium move in a direction parallel to the direction that the wave moves.