CUET Biology MCQs Unit II Genetics and Evolution

CUET Biology Principles of Inheritance and Variation MCQs

Question: The crossing of F₁ to homozygous recessive parent is called

a) back cross

b) test cross

c) F₁ cross    

d) all of these

Answer : B

Question: Linkage reduces the frequency of

a) hybrids.

b) all parental types.

c) homozygous recessive parents.

d) heterozygous recessive parents.

Answer : A

Question: All genes located on the same chromosome

a) Form one linkage group

b) Will not from any linkage groups

c) Form interactive groups that affect the phenotype

Answer : A

Question: In sickle cell anaemia glutamic acid is replaced by valine. Which one of the following triplets codes for valine?

a) G U G

b) G A A

c) A A G

d) G G G

Answer : A

Question: A disease caused by an autosomal primary non-disjunction is

a) Down's syndrome

b) Klinefelter's syndrome

c) Turner's syndrome

d) Turner's syndrome

Answer : A

Question: A Across between two tall plants resulted in offspring having few dwarf plants. What would be the genotypes of both the parents?

a) Tt and Tt

b) TT and Tt

c) TT and TT

d) Tt and tt

Answer : A

Question: How many pairs of contrasting characters in pea plants were studied by Mendel in his experiments?

a) 7

b) 5

c) 6

d) 4

Answer : A

Question: Two linked genes a and b show 20% recombination.

The individuals of a dihybrid cross between ++ /++ × ab/ab shall show gametes

a) + +80 : ab 20

b) + + 50 : ab 50

c) + + 40 : ab 40 : + a 10 : + b : 10

d) + + 30 : ab 30 : + a 20 : + b : 20

Answer : C

Question: Mendel’s last law is 

a) segregation

b) dominance

c) independent assortment

d) polygenic inheritance

Answer : C

Question: A gene pair hides the effect of another. The phenomenon is 

a) epistasis

b) dominance

c) mutation

d) None of these

Answer : A

Question: When a certain character is inherited only through female parent, it probably represents

a) multiple plastid inheritance 

b) cytoplasmic inheritance

c) incomplete dominance

d) Mendelian nuclear inheritance

Answer : B

Question: Which of the following is suitable for experiment on linkage? 

a) aaBB × aaBB

b) AABB × aabb

c) AaBb × AaBb

d) AAbb × AaBB

Answer : B

Question: A cross between pure tall pea plant with green pods and dwarf pea plant with yellow pods will produce dwarf F2 plants out of 16

a) 9

b) 3

c) 4

d) 1

Answer : C

Question: When a single gene influences more than one traits it is called

a) pleiotropy

b) epistasis

c) pseudodominance

d) None of these

Answer : A

Question: Albinism is known to be due to an autosomal recessive mutation. The first child of a couple with normal skin pigmentation was an albino. What is the probability that their second child will also be an albino ? 

a) 100%

b) 25%

c) 50%

d) 75%

Answer : B

Question: A and B genes are linked. What shall be the genotype of progeny in a cross between AB/ab and ab/ab? 

a) AAbb and aabb

b) AaBb and aabb

c) AABB and aabb

d) None of these

Answer : B

Question: Which one of the following traits of garden pea studied by Mendel was a recessive feature?

a) Green pod colour

b) Round seed shape

c) Axial flower position

d) Green seed colour

Answer : D

Question: One of the parents of a cross has mutation in its mitochondria. In that cross, that parent is taken as a male. During segregation of F2 progenies that mutation is found in 

a) one-third of the progenies

b) none of the progenies

c) all of the progenies

d) fifty per cent of the progenies

Answer : B

Question: Sickle cell anaemia is

a) caused by substitution of valine by glutamic acid in the beta globin chain of haemoglobin.

b) caused by a change in a single base pair of DNA.

c ) characterized by elongated sickle like RBCs with a nucleus.

d) an autosomal linked dominant trait.

Answer : B

Question: Extra chromosome ‘X’ is present in which one of the following cases?

a) Down syndrome

b) Klinefelter syndrome

c) Turner syndrome

d) Bleeder’s disease

Answer : B

Question: Occasionally, a single gene may express more than one effect. The phenomenon is called

a) pleiotropy

b) mosaicism

c) polygeny

d) multiple allelism

Answer : A

Question: It is said that Mendel proposed that the factor controlling any character is discrete and independent. This proposition was based on the

a) observations that the offspring of a cross made between the plants having two contrasting characters shows only one character without any blending

b) self pollination of F₁ offsprings

c) cross pollination of parental generations

d) All of these

Answer : A

Question: A pleiotropic gene

a) controls multiple traits in an individual

b) controls multiple traits in an individual

c) is a gene evolved during Pliocene

d) control of trait only in combination with another gene

Answer : A

Question: ABO blood group system is due to

a) multifactor inheritance

b) incomplete dominance

c) multiple allelism

d) epistasis

Answer : C

Question: Sex is determined in human beings

a) by ovum.

b) at time of fertilization.

c) 40 days after fertilization.

d) seventh to eight week when genitals differentiate in foetus.

Answer : B

Question: If a genetic disease is transferred from a phenotypically normal but carrier female to only some of the male progeny, the disease is

a) Sex-linked recessive

b) Autosomal dominant

c) Sex-linked dominant

d) Autosomal recessive

Answer : A

Question: If a colour-blind man marries a woman who is homozygous for normal colour vision, the probability of their son being colour-blind is

a) 0

b) 0.5

c) 1

d) 2

Answer : A

Question: Which of the following will not result in variations among siblings?

a) Linkage

b) Mutation

c) Independent assortment of genes

d) Crossing over

Answer : A

Question: A normal green male maize is crossed with albino female. The progeny is albino because

a) trait for albinism is dominant

b) the albinos have biochemical to destroy plastids derived from green male

c) plastids are inherited from female parent

d) green plastids of male must have mutated

Answer : C

Question: The contrasting pairs of factors in Mendelian crosses are called 

a) multiple alleles

b) allelomorphs

c) alloloci

d) paramorphs

Answer : B

Question: In a cross between AABB × aabb, the ratio of F₂ genotypes between AABB, AaBB, Aabb and aabb would be 
a) 9 : 3 : 3 : 1
b) 2 : 1 : 1 : 2
c) 1 : 2 : 2 : 1
d) 7 : 5 : 3 : 1

Answer : C

Question: Mendel studied interitance of seven pairs of traits in pea which can have 21 possible combinations. If you are told that in one of these combinations, independent assortment is not observed in later studies, your reaction will be 

a) independent assortment principle may be wrong

b) Mendel might not have studied all the combinations

c) it is impossible

d) later studies may be wrong

Answer : B

Question: A fruit fly exhibiting both male and female traits is 

a) heterozygous

b) gynandromorph

c) hemizygous

d) gynander

Answer : B

Question: Alleles that produce independent effects in their heterozygous condition are called

a) codominant alleles

b) epistatic alleles

c) complementary alleles

d) supplementary alleles

Answer : A

Question: Hybridization between Tt × tt gives rise to the progeny of ratio 

a) 1 : 1

b) 1 : 2 : 1

c) 1 : 2

d) 4 : 1

Answer : A

Question: Extranuclear inheritance occurs in 

a) Killer Paramecium

b) Killer Amoeba

c) Euglena

d) Hydra

Answer : A

Question: The genes controlling the seven pea characters studied by Mendel are now known to be located on how many different chromosomes?

a) Five

b) Four

c) Seven

d) Six

Answer : B

Question: In a dihybrid cross, F₂ phenotypic ratio is 13 : 3. It is case of

a) complementary genes

b) epistatic genes

c) multigenic inheritance

d) incomplete dominance

Answer : B

Question: The number of phenotypes in ABO blood groups is

a) 1

b) 4

c) 6

d) 8

Answer : B

Question: Mendel’s Law of independent assortment holds good for genes situated on the:

a) non-homologous chromosomes

b) homologous chromosomes

c) extra nuclear genetic element

d) same chromosome

Answer : A

Question: _________ is a type of trait whose phenotype is influenced by more than one gene

a) Polygenic trait

b) Monogenic trait

c) Both

d) None of these

Answer : A

Question: In humans, the dominance relationship between the A and B alleles of the ABO blood group gene is an example of

a) complete dominance

b) incomplete dominance

c) codominance

d) epistasis

Answer : C

Question: Hb^A and Hb^S alleles of normal and sickle celled RBC are

a) dominant-recessive alleles.

b) polygenic alleles.

c) codominant alleles.

d) multiple alleles.

Answer : C

Question: Among the following characters, which one was not considered by Mendel in his experiments on pea?

a) Among the following characters

b) Seed – Green or Yellow

c) Pod – Inflated or Constricted

d) Pod – Inflated or Constricted

Answer : A

Question: In a dihybrid cross, if you get 9:3:3:1 ratio it denotes that

a) The allels of two genes are segregating independently.

b) It is a case of multiple allelism

c) It is a multigenic inheritance

d) The allels of two genes are interacting with each other

Answer : A

Question: Multiple alleles control inheritance of

a) phenylketonuria

b) colourblindness

c) sickle cell anaemia

d) blood groups

Answer : D

Question: RR (red) Antirrhinum is crossed with WW (white) one. Offspring RW are pink. This is an example of 

a) dominant-recessive

b) incomplete dominance

c) hybrid

d) supplementary genes

Answer : B

Question: Two dominant non-allelic genes are 50 map units apart. The linkage is 

a) cis type

b) trans type

c) complete

d) absent/incomplete

Answer : D

Question: When two genetic loci produce identical phenotypes in cis and trans position, they are considered to be

a) pseudoalleles

b) different genes

c) multiple alleles

d) parts of same gene

Answer : A

Question: How many types of genetically different gametes will be produced by a heterozygous plant having genotype AABbCc ? 

a) Two

b) Four

c) Six

d) Nine

Answer : B

Question: During organ differentiation in Drosophila, an organ is modified to another organ (such as wings may be replaced by legs) Genes responsible for such metamorphosis are called 

a) double dominant genes

b) plastid genes

c) complementary genes

d) homeotic genes

Answer : D

Question: Extra nuclear chromosomes occur in 

a) peroxisome, ribosome

b) chloroplast and mitochondria

c) mitochondria and ribosome

d) chloroplast and lysosome

Answer : B

Question: Two crosses between the same pair of genotypes or phenotypes in which the sources of the gametes are reversed in one cross, is known as 

a) dihybrid cross

b) reverse cross

c) test cross

d) reciprocal cross

Answer : D

Question: In sickle-cell anaemia, shape of RBCs under oxygen tension becomes

a) biconcave disc like

b) elongated and curved

c) circular                  

d) spherical

Answer : B

Question: A character which is expressed in a hybrid is called

a) dominant   

b) recessive

c) co-dominant

d) epistatic

Answer : A

Question: Two genes ‘A’ and ‘B’ are linked. In a dihybrid cross involving these two genes, the F₁ heterozygote is crossed with homozygous recessive parental type (aa bb). What would be the ratio of offspring in the next generation?

a) 1 : 1 : 1: 1

b) 9 : 3 : 3 : 1

c) 3 : 1

d) 1 : 1

Answer : A

Question: Distance between the genes and percentage of recombination shows

a) a direct relationship

b) an inverse relationship

c) a parallel relationship

d) no relationship

Answer : A

Question: Which one from those given below is the period

a) 1856 - 1863

b) 1840 - 1850

c) 1857 - 1869

d) 1870 - 1877

Answer : A

Question: A dihybrid condition is 

a) ttRr

b) Tt rr

c) tt rr

d) Tt Rr

Answer : D

Question: Haploid plants are preferred over diploids for mutation study because in haploids 

a) recessive mutation express immediately

b) induction of mutations is easier

c) culturing is easier

d) dominant mutation express immediately

Answer : A

Question: Which one of the following characters studied by Mendel in garden pea was found to be dominant ? 

a) Green seed colour

b) Terminal flower position

c) Green pod colour

d) Wrinkled seed

Answer : C
 

CUET Biology Evolution MCQs

Question: Stanley L. Miller conducted experiments before 1953 on prebiotic earth environment using special apparatus. The primary surprising products were

a) amino acids

b) peptides

c) nucleotides 

d) simple sugars

Answer : A

Question: What is common amongst whale, seal and shark?

a) Homoiothermy

b) Seasonal migration

c) Thick subcutaneous fat

d) Convergent evolution

Answer : D 

Question: Which of the following is used as an atmospheric pollution indicator?

a) Lichens

b) Lepidoptera

c) Lycopersicon

d) Lycopodium

Answer : A

Question: Analogous organs arise due to

a) convergent evolution

b) genetic drift

c) artificial selection

d) divergent evolution

Answer : A

Question: ___________ is a vestigial organ

a) Vermiform appendix

b) None of the above

c) Papillae

d)  Intestinal villi

Answer : A

Question: For the MN-blood group system, the frequencies of M and N alleles are 0.7 and 0.3, respectively. The expected frequency of MN-blood group bearing organisms is likely to be

a) 42%

b) 49%

c) 9%

d) 58%

Answer : A

Question: The experiment that simulated conditions thought to be present on the early earth

a) Miller–Urey experiment

b) Schiehallion experimen

c) Geiger–Marsden experiment

d) Hershey–Chase experiment

Answer : A

Question: Parallelism is 

a) adaptive divergence

b) adaptive divergence of widely separated species

c) adaptive convergence of widely different species

d) adaptive convergence of closely related groups

Answer : D 

Question: Which one does not favour Lamarckian concept of inheritance of acquired characters?

a) Lack of pigment in cave dwellers

b) Absence of limbs in snakes

c) Presence of webbed toes in aquatic birds

d) Melanization of peppered moth in industrial areas

Answer : D 

Question: Genetic drift operates only in 

a) smaller populations

b) larger populations

c) Mendelian populations

d) island populations

Answer : A

Question: Genetic drift operates in 

a) small isolated population

b) large isolated population

c) fast reproductive population

d) slow reproductive population

Answer : A

Question : The Finches of Galapogas islands provide an evidence in favour of

a) biogeographical evolution

b) special creation

c) evolution due to mutation

d) retrogressive evolution EBD_7209 Evolution 253

Answer : A

Question : A population is in Hardy- weinberg equilibrium for a gene with only two alleles. If the gene frequency of an allele A is 0.7, the genotype frequency of Aa is

a) 0.21

b) 0.42

c) 0.36 

d) 0.7

Answer : B

Question :  In 1953 S. L. Miller created primitive earth conditions in the laboratory and gave experimental evidence for origin of first form of life from preexisting non-living organic molecules. The primitive earth conditions created include: 

a) high temperature, volcanic storms, reducing atmosphere containing CH₄, NH₃ etc

b) high temperature, volcanic storms, non-reducing atmosphere

c) low temperature, volcanic storms, reducing atmosphere

d) low temperature, volcanic storms, atmosphere rich in oxygen

Answer : A

Question :  The principle of competitive exclusion was stated by

a) G.F. Gause

b) C. Darwin

c) Verhulst and Pearl

d) Mac Arthur

Answer : A

Question :  A population will not exist in Hardy Weinberg equilibrium if

a) individuals mate selectively

b) there are no mutations

c) there are no mutations

d) All of these

Answer : A

Question :  Basic principles of embryonic development were pronounced by 

a) von Baer

b) Weismann

c) Haeckel

d) Morgan

Answer : A

Question : ‘Golden age of dinosaurs’/Age of reptiles was 

a) Mesozoic

b) Coenozoicc

c) Palaeozoic

d) Psychozoic

Answer : A

Question : Darwin’s finches provide an excellent evidence in favour of evolution. This evidence comes from the field of 

a) Biogeography

b) Anatomy

c) Embryology

d) Palaeontology

Answer : A

Question : Which of the following is homologous organ? 

a) Wings of birds and locust

b) Wings of birds (sparrow) and pectoral fins of fish

c) Wings of bat and butterfly

d) Legs of frog and cockroach

Answer : B

Question : What kind of evidence suggested that man is more closely related with chimpanzee than with other hominoid apes? 

a) Evidence from DNA from sex chromosomes only

b) Comparison of chromosomes morphology only

c) Evidence from fossil remains and the fossil mitochondrial DNA alone

d) Evidence from DNA extracted from sex chromosomes, autosomes and mitochondria

Answer : D 

Question : Evolutionary history of an organism is known as 

a) Ancestry

b) Palaeontology

c) Ontogeny

d) Phylogeny

Answer : D 

Question : Which one of the following statements about fossil human species is correct ? 

a) Fossils of Homo neanderthalensis have been found recently in South America

b) Neanderthal man and Cro-magnon man did exist for sometime together

c) Australopithecus fossils have been found in Australia

d) Homo erectus was preceded by Homo habilis

Answer : D 

Question : Which of the following is closest relative of man? 

a) Chimpanzee

b) Gorilla

c) Orangutan

d) Gibbon

Answer : A

Question : Among the human ancestors the brain size was more than 1000 cc in 

a) Homo neanderthalensis

b) Homo erectus

c) Ramapithecus

d) Homo habilis

Answer : A

Question : Which of the following had the smallest brain capacity ? 

a) Homo sapiens

b) Homo neanderthalensis

c) Homo habilis

d) Homo erectus

Answer : C

Question: Who proposed that the first form of life come from preexisting non- living molecules?

a) Oparin and Haldane

b) de Vries and Haldane

c) Darwin and Lamarck

d) Louis Pasteur and Miller

Answer : A

Question: Darwin’s finches are a good example of

a) convergent evolution

b) industrial melanism

c) connecting link

d) adaptive radiation

Answer : D 

Question: Appearance of antibiotic-resistant bacteria is an example of

a) pre-existing variation in the population

b) divergent evolution

c) transduction

d) adaptive radiation

Answer : A

Question: Fossils are generally found in

a) Sedimentary rocks

b) Igneous rocks

c) Metamorphic rocks

d) Any type of rock

Answer : A

Question: “Continuity of germplasm” theory was given by 

a) deVries 

b) Weismann

c) Darwin

d) Lamarck

Answer : B

Question: Weismann cut off tails of mice generation after generation but tails neither disappeared nor shortened showing that 

a) Darwin was correct

b) tail is an essential organ

c) mutation theory is wrong

d) Lamarckism was wrong in inheritance of acquired characters

Answer : D 

Question: Frequency of a character increases when it is 

a) recessive

b) dominant

c) inheritable 

d) adaptable

Answer : D 

Question: Darwin’s theory of pangenesis shows similarity with theory of inheritance of acquired characters then what will be correct according to it? 

a) Useful organs become strong and developed while useless organs become extinct. These organs help in struggle for survival

b) Size of organs increase with ageing

c) Development of organs is due to will power

d) There should become physical basis of inheritance

Answer : D 

Question: Darwin in his ‘Natural Selection Theory’ did not believe in any role of which one of the following in organic evolution? 

a) Discontinuous variations

b) Parasites and predators as natural enemies

c) Survival of the fittest

d) Struggle for existence

Answer : A

Question : Single step large mutation leading to speciation is also called

a) Founder effect      

b) saltation

c) branching descent

d) natural selection

Answer : B

Question :  The first mammals were like

a) chimpanzee

b) gorilla

c) shrews  

d) reptiles

Answer : C

Question :  The chronological order of human evolution from early to the recent is

a) Ramapithecus → Australopithecu s →Homo habilis → Homo erectus

b) Australopithecus → Homo habilis → Ramapithecus → Homo erectus

c) Australopithecus → Ramapithecus → Homo habilis → Homo erectus

d) All of these

Answer : A

Question :  Correct order is 

a) Palaeozoic —>Archaeozoic —>Coenozoic

b) Archaeozoic —> Palaeozoic —> Proterozoic

c) Palaeozoic —> Mesozoic —> Coenozoic

d) Mesozoic —> Archaeozoic —> Proterozoic

Answer : C

Question : Which one of the following sets includes only the vestigial structures in man? 

a) Body hair, olecranon process, coccyx, patella

b) Wisdom teeth, mammary glands, coccyx, patella

c) Coccyx, nictitating membrane, vermiform appendix, ear muscles

d) Coccyx, body hair, ear ossicles, vermiform appendix

Answer : C

Question : In which era reptiles were dominant? 

a) Coenozoic era

b) Mesozoic era

c) Palaeozoic era

d) Archaeozoic era

Answer : B

Question : In recent years, DNA sequences (nucleotide sequence) of mtDNA and Y-chromosomes were considered for the study of human evolution, because 

a) they can be studied from the samples of fossil remains

b) they are small and, therefore, easy to study

c) they are uniparental in origin and do not take part in recombination

d) their structure is known in greater detail

Answer : C

Question : Which of the following is the relatively most accurate method for dating of fossils?

a) Radio-carbon method 

b) Potassium-argon method

c) Electron-spin resonance method

d) Uranium-lead method

Answer : C

Question : Common origin of man and chimpanzee is best shown by 

a) banding pattern in chromosomes number 3 and 6

b) cranial capacity

c) binocular vision

d) dental formula

Answer : A

Question : Which of the following is correct order of evolutionary history of man? 

a) Peking man, Homo sapiens, Neanderthal, Cro-magnon

b) Peking man, Neanderthal, Homo sapiens, Cro-magnon

c) Peking man, Heidelberg man, Neanderthal, Cro-magnon

d) Peking man, Neanderthal, Homo sapiens, Heidelberg man

Answer : C

Question : The extinct human who lived 1,00,000 to 40,000 years ago, in Europe, Asia and parts of Africa, with short stature, heavy eye brows, retreating for heads, large jaws with heavy teeth, stocky bodies a lumbering gait and stooped posture was 

a) Cro-magnon humans

b) Rampithecus

c) Homo habilis

d) Neanderthal human

Answer : D 

Question: Analogous organs are

a) different in origin but perform similar functions.

b) common in origin and perform common functions.

c) common in origin but perform different functions.

d) different in origin and perform different functions.

Answer : A

Question: The theory of spontaneous generation stated that

a) life can arise from non-living things only

b) life arises spontaneously, neither from living nor from the non-living.

c) life can arise from both living and non-living

d) life arose from living forms only

Answer : A

Question: The force that initiates evolution is

a) Variation

b) Mutation

c) Extinction

d) Adaptation

Answer : A

Question: Which of the following is an example for link species?

a) Lobe fish

b) Dodo bird

c) Sea weed

d) Tyrannosaurus rex

Answer : A

Question: Which was absent in the atmosphere at the time of origin of life? 

a) NH₃ 

b) H₂

c) O₂ 

d) CH

Answer : C

Question: Identify the correct sequence in which the following substances have appeared during the course of evolution of life on earth 

a) glucose, amino acids, nucleic acids, proteins

b) ammonia, amino adds, proteins, nucleic acids

c) water, amino acids, nucleic acids, enzymes

d) amino acids, ammonia, phosphates, nucleic acids

Answer : B

Question : The term ‘Survival of Fittest’ was used by

a) Charles Darwin

b) Herbert Spencer

c) Jean Baptiste   

d) Hugo de Vries

Answer : B 

Question :  Random genetic drift in a population probably results from 

a) highly genetically variable individuals.

b) interbreeding within the population.

c) constant low mutation rate.

d) large population size.

Answer : A

Question :  Analogous structures are a result of

a) Convergent 

b) Convergent evolution

c) Shared ancestry

d) Stabilizing selection

Answer : B

Question : The homologous organs are those that show similarity in 

a) size

b) origin

c) function

d) appearance

Answer : B

Question : Convergent evolution is illustrated by

a) dogfish and whale 

b) rat and dog

c) bacterium and protozoan

d) starfish and cuttle fish 

Answer : A

Question : One of the important consequences of geographical isolation is 

a) no change in the isolated fauna

b) preventing speciation

c) speciation through reproductive isolation

d) random creation of new species

Answer : C

Question: Thorn of Bougainvillea and tendril of Cucurbita are examples of

a) retrogressive evolution.

b) analogous organs.

c) homologous organs.

d) vestigial organs.

Answer : C

Question: The bones of forelimbs of whale, bat, cheetah and man are similar in structure, because

a) they share a common ancestor

b) one organism has given rise to another

c) they perform the same function

d) the have biochemical similarities

Answer : A

Question: The earliest geological time period among the following is

a) Cambrian

b) Permian

c) Jurassic

d) Quaternary

Answer : A