Evolution

PROBLEM SOLVING-2

BQ29Q443

(A) Neo Darwinism (B) Natural selection

(C) Mutation (D) Neo Lamarckism

Industrial melanism is an example of NEET - 2015

BQ29S443

Ans [B]

Within a period of years in industrial or polluted areas the dark species has almost

replaced the light species. This is called industrial melanism because of its association

with the sooty atmosphere of industry. It is an example of natural selection.

BQ29Q444

(A) Transduction (B) Chromosomal aberrations

(C) Genetic drift (D) Recombination

Which is the most common mechanism of genetic variation in the population of a

sexually reproducing organism? NEET - 2015

BQ29S444

Ans [D]

Recombination - when two molecules of DNA exchange pieces of their genetic material

with each other during meiosis.

BQ29Q446

(A) Small isolated population (B) Large isolated population

(C) Non-reproductive population (D) Slow reproductive population

Genetic drift operates in NEET - 2016

BQ29S446

Ans [A]

The genetic drift is a drastic change in allele frequency when population size is

very small. Its effects are more marked in a small isolated population.

BQ29Q447

(A) P2 (B) 2pq

(C) pq (D) q2

In Hardy- Weinberg equation, the frequency of heterozygous individual is represented

by NEET - 2016

BQ29S447

Ans [B]

Hardy- Weinberg principle states that the allele frequencies in a population are stable

and remain constant from generation to generation. This can be expressed by the

equation :

p2 + 2pq + q2 = 1

or p + q 2 = 1

Where p2 represents frequency of homozygous dominant genotype 2pq represents the

frequency of heterozygous genotype and q2 represents the frequency of homozygous

recessive genotype.

BQ29Q448

(A) I,II,III,IV (B) I,III,II,IV

(C) II,III,I,IV (D) II,III,IV,I

Which of the following is the correct sequence of events in the origin of life?

I. Formation of protobionts,

II. Synthesis of organic monomers.

III. Synthesis of organic polymers.

IV. Formation of DNA-based genetic systems.

NEET - 2016

BQ29S448

Ans [C]

The sequential manner of events of origin of life is as follows

Synthesis of organic monomers → Synthesis of organic polymers → Formation of

protobionts → Formation of DNA-based genetic systems

BQ29Q449

(A) C Darwin (B) GF Gause

(C) MacArthur (D) Verhuisd and Pearl

The principle of competitive exclusion was stated by NEET - 2016

BQ29S449

Ans [B]

The principle of competitive exclusion is stated by GF Gause. He studied the effects of

interspecific competition between two closely related species.

He stated that two species competing for the same food resource can not coexist at the

same place as highest degree of competitiveness exists between them.

BQ29Q450

(A) Convergent evolution (B) Shared ancestry

(C) Stabilizing selection (D) Divergent evolution

Analogous structures are a result of NEET - 2016

BQ29S450

Ans [A]

Analogous structures are a result of convergent evolution. When organisms with

completely different organization, living in the same habitat come to possess

superficial resemblance, this is known as convergent evolution.

BQ29Q451

(A) Wing of a moth (B) Hind limb of rabbit

(C) Flipper of whale (D) Dorsal fin of a shark

Which of the following structures is homologous to the wing of a bird? NEET - 2016

BQ29S451

Ans [C]

Wings of bird and flipper of whale are modified fore limbs of the two organisms so

have same origin wings help in flying and flippers help in swimming, but thus perform

the different functions.

BQ29Q454

(A) Lichens (B) Conifers

(C) Algae (D) Fungi

Which of the following are most suitable indicators of SO2 pollution in the

environment? NEET - 2015

BQ29S454

Ans [A]

Lichens are useful bioindicators for air pollution, especially sulphur dioxide

pollution since they derive their water and essential nutrients mainly from the

atmosphere rather than from soil.

BQ29Q455

(A) Homo erectus (B) Homo sapiens

(C) Homo neanderthalensis (D) Homo habilis

Which of the following had the smallest brain capacity? NEET - 2015

BQ29S455

Ans [D]

Homo habilis also called the 'tool maker' or 'hand man' had a brain capacity of 700 cc.

Homo erectus had a brain or cranial capacity of 800-1000 cc.

Homo neanderthalensis has the largest brain capacity i.e., averaged 1400 cubic

centimetres.

Homo sapiens or modern man showed a slight reduction in brain/cranial capacity, i.e.

1300-1600 cc will be an average of 1450 cc.

BQ29Q456

(A) Individuals mate selectively (B) There are no mutations

(C) There is no migration (D) The population is large

A population will not exist in Hardy-Weinberg equilibrium if NEET - 2015

BQ29S456

Ans [A]

Hardy-Weinberg equilibrium exists in population only when following conditions are

present.

No mutation

No gene flow

No genetic drift

No genetic recombination

No natural selection pressure.

If the individuals in the population mate selectively, it will lead to mutation thus

shifting the Hardy-Weinberg equilibrium.

BQ29Q457

(A) 0.4 (B) 0.5

(C) 0.6 (D) 0.7

In a population of 1000 individuals 360 belongs to genotype AA, 480 to Aa and the

remaining 160 to aa. Based on this data, the frequency of allele A in the population is

NEET - 2014

BQ29S457

Ans [C]

BQ29Q458

(A) Analogous organs (B) Adaptive radiation

(C) Homologous organs (D) Convergent evolution

Forelimbs of cat/ lizard used in walking; forelimbs of whale used in swimming and

forelimbs of bats used in flying are an example of NEET - 2014

BQ29S458

Ans [C]

Homologous organs, are those organs which have a common fundamental

anatomical plan and similar embryonic origin but perform varied functions.

BQ29Q459

Which one of the following are analogous structures? NEET - 2014

(A) Wings of eagle and wings of pigeon

(B) Gills of prawn and lungs of man

(C) Thorns of Bougainvillea and tendrils of Cucurbita

(D) Flippers of dolphin and legs of horse

BQ29S459

Ans [B]

Analogous organs are the structures of different species having similar or

corresponding functions but different structure. They do not belong to the same

evolutionary origins.

BQ29Q461

(A) Natural selection (B) Convergent evolution

(C) Non-random evolution (D) Adaptive radiation

The process by which organisms with different evolutionary history evolve similar

phenotypic adaptations in response to a common environment challenge, is called

NEET - 2013

BQ29S461

Ans [B]

BQ29Q493

When two species of different genealogy come to resemble each other as a

result of adaptation, the phenomenon is termed:-

(A) Convergent evolution (B) Divergent evolution

(C) Microevolution (D) Co-evolution

BQ29S493

Ans [A]

Convergent evolution

BQ29Q495

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

BQ29S495

Darwin's finches of Galapagos islands had common ancestors later on whose

beaks modified according to their feeding habits. These provide evidence of

geographical distribution.

Ans [A]

Biogeographical Evolution

BQ29Q496

One of the important consequences of geographical isolation is:-

(A) Random creation of new species

(B) No change in the isolated fauna

(C) Preventing Speciation

(D) Speciation through reproductive isolation

BQ29S496

Ans [D]

Speciation through reproductive isolation

Speciation refers to a lineage-splitting event that is used to produce two or more

separate species. The process takes place as a result of geographical isolation

caused due to natural disasters and natural changes and also due to the reduction

in gene flow. One of the main consequence of geographical isolation is speciation

through reproductive isolation

BQ29S497

Ans [D]

BQ29Q498

The concept of chemical evolution is based on-

(A) Possible origin of life by combination of chemicals under suitable

environmental conditions

(B) Crystallization of chemicals

(C) Interaction of water, air and clay under intense heat

(D) Effect of solar radiation on chemicals

BQ29S498

Concept of chemical evolution refers to origin of life from non living matter. First

inorganic compounds and then organic compounds were formed in accordance

with ever changing environmental conditions

Ans [A]

Possible origin of life by combination of chemicals under suitable

environmental conditions

BQ29Q499

Among the human ancestors the brain size was more than 1000 CC in:-

(A) Homo habilis (B) Homo neanderthalensis

(C) Homo erectus (D) Ramapithecus

BQ29S499

Homo neanderthalensis and Cro-Magnon man are believed to be immediate

precursors of modern humans. Their brains may have been slightly larger than

present day humans and both groups had significantly larger brains than H.

erectus. Both Ramapithecus and Homo habilis were primitive to both

Neanderthalensis and Cro-Magnon man.

Ans [B]

Homo neanderthalensis

BQ29Q501

Which one of the following amino-acids was not found to be synthesized in

Miller's experiment ?

(A) Glycine (B) Aspartic acid

(C) Glutamic acid (D) Alanine

BQ29S501

Ans [C]

Glutamic acid

Miller and Urey were the two scientists who recreated the conditions of primitive earth in laboratory and abiotically synthesized amino acids and bases. They synthesized glycine, aspartic acid and alanine in abundance quantities while glutamic acid is not synthesized in their experiment.

BQ29Q502

Niche overlap indicates-

(A) Active cooperation between two species

(B) Two different parasites on the same host

(C) Sharing of one or more resources between the two species

(D) Mutualism between two species

BQ29S502

Ans [C]

Sharing of one or more resources between the two species

Niche overlap is a measure of the association of two or more species and this

shows their similar habitat requirements and might even include the competition

between the species if the resources are limited.

BQ29Q504

Jurassic period of the Mesozoic era characterized by-

(A) Gymnosperms are dominant plants and first birds appear

(B) Radiation of reptiles and origin of mammal like reptiles

(C) Dinosaurs become extinct and angiosperms appear

(D) Flowering plants and first dinosaurs appear

BQ29S504

Ans [A]

Gymnosperms are dominant plants and first birds appear

Jurassic period is the second geological period of the mesozoic era. In this

period the gymnosperms were dominant and the first primitive bird ,

Archaeopteryx , also made its appearance

BQ29Q505

At a particular locus, frequency of 'A' allele is 0.6 and that of 'a' is 0.4. What

would be the frequency of heterozygotes in a random mating population at

equilibrium -

(A) 0.24 (B) 0.16

(C) 0.48 (D) 0.36

BQ29S505

Ans [C]

0.48

Accordingly to Hardy-Wienberg principle, P² + 2PQ + Q² = 1 , where P and Q are the

individual frequency of dominant amd recessive allele respectively at a particular locus and

the term 2PQ represents the frequency of heterozygotes in a randomly mating population.

Hence, the answer should be (2*0.6*0.4) = 0.48 .

BQ29Q507

Which one of the following phenomena supports Darwin's concept of

natural selection in organic evolution -

(A) Production of 'Dolly', the sheep by cloning

(B) Development of organs from 'stem' cells for organ transplantation

(C) Development of transgenic animals

(D) Prevalence of pesticide resistant insects

BQ29S507

Ans [D]

Prevalence of pesticide resistant insects

Darwin's Theory of Evolution by Natural Selection

• More individuals are produced each generation that can survive.

• Phenotypic variation exists among individuals and the variation is heritable.

• Those individuals with heritable traits better suited to the environment will survive.

• Origin of new species

BQ29Q508

Which of the following is the relatively most accurate method for dating of

fossils -

(A) Electron-spin resonance method

(B) Uranium-lead method

(C) Potassium–argon method

(D) Radio-carbon method

BQ29S508

Ans [A]

Electron-spin resonance method

Electron spin resonance method is the most accurate method for dating of fossils. It

measures number of charges occupying deep traps crystal band gap.

BQ29Q510

De Vries gave his mutation theory on organic evolution while working on -

(A) Oenothera lamarckiana (B) Drosophila melanogaster

(C) Pisum sativum (D) Althea rosea

BQ29S510

Ans [A]

Oenothera lamarckiana

According to him, new species are not formed by continuous variations but by sudden

appearance of variations, which he named as mutations. Hugo de Vries stated that

mutations are heritable and persist in successive generations.He conducted his

experiments on Oenothera Lamarckian, (Evening Primrose)

BQ29Q511

Convergent evolution is illustrated by : -

(A) Rat and dog (B) Bacterium and protozoan

(C) Starfish and cuttle fish (D) Dogfish and whale

BQ29S511

Convergent development is the securing of same or comparable characters by

indirectly related lines of plummet. Dogfish (Pisces) and whale (vertebrates) have

procured sea-going characters however indirectly related.

Ans [D]

Dogfish and whale

BQ29Q512

Which one of the following sequences was proposed by Darwin and Wallace

for organic evolution : -

(A) Overproduction, variations, constancy of population size, natural selection

(B) Variations, constancy of population size, overproduction, natural selection

(C) Overproduction, constancy of population size, variations, natural selection

(D) Variation, constancy of population size, variations, natural selection

BQ29S512

Organisms tend to increase the number of offsprings in the individual for survival

in number. Then the interspecific, intraspecific, extra specific struggle for

existence occurs. Then small changes occur from the parent generation to the

next progenies which acts as a raw material for a source of evolution. And nature

selects the useful or adaptive variation.

Ans [C]

Overproduction, constancy of population size, variations, natural selection

BQ29Q514

In recent years, DNA sequences (nucleotide sequence) of mt-DNA and Y

chromosomes were considered for the study of human evolution, because : -

(A) They are small, and therefore, easy to study

(B) They are uniparental in origin and do not take part in recombination

(C) Their structure is known in greater detail

(D) They can be studied from the samples of fossil remains

BQ29S514

Ans [B]

They are uniparental in origin and do not take part in recombination

•In human cells, chromosomes are present in both nucleus as well as mitochondria. Most of the proteins in humans are encoded by the nuclear genome but mitochondrial DNA plays a significant role too.•Mitochondria contain their own DNA that is separate from the nuclear DNA. mtDNAshows maternal inheritance.•The nuclear DNA which is equally inherited from both the mother and the father, mitochondrial DNA (mtDNA) is inherited only from the mother. This makes mitochondrial DNA particularly interesting and useful for human evolutionary studies.•Normally, mtDNA is identical to that of the mother. But like all DNA molecules, mtDNA molecules also undergo mutations that change the sequence slightly. Thus, mtDNA of a daughter cell would be different from the mtDNA of its mother and this difference is proportional to the amount of time that has passed and therefore proves to be very useful for studying human evolution.•Similar is the case with Y chromosome that is inherited from the father and, therefore, follows a similar evolutionary pattern like mtDNA.

BQ29Q515

Industrial melanism is an example of : -

(A) Drug resistance

(B) Darkening of skin due to smoke from industries

(C) Protective resemblance with the surroundings

(D) Defensive adaptation of skin against ultraviolet radiations

BQ29S515

In this case moths with dark coloured will be selected by nature and hence they will

be reproductively successful as compared to moths of light colour. Hence it is an

example of protective colouration.

Ans [C]

Protective resemblance with the surroundings