CBSE Questions for Class 12 Medical Biology Evolution Quiz 6 - MCQExams.com

T. R. Malthus wrote
  • An essay on population
  • Origin of species
  • Discovery of India
  • Text book of mathematics
Which were dominant in mesozoic?
  • Dinosaurs
  • Gymnosperms
  • Fishes
  • Mammals
The earliest hominids that developed more than four million years ago were 
  • Homo erectus
  • Australopithecus
  • Cro-Magnon man
  • Neanderthal man
Dinosaurs were abundant in
  • Jurassic
  • Devonian
  • Permian
  • Pleistocene
Darwin's finches show
  • Adaptive radiation
  • Parallel evolution
  • Homology
  • Natural selection
Which of the following statement is correct about Cro-Magnon man?
  • Cro-Magnon is an advanced stage of man's evolution more advanced than Homo erectus.
  • Predecessor of Homo neanderthalensis.
  • Direct ancestor of modern man.
  • Cro-Magnon man lived during last ice age.
According to studies, the humans first originated in _____________
  • America
  • Australia
  • Asia
  • Africa
Biological concept of species is mainly based on
  • Reproductive isolation
  • Morphological features only
  • Methods of reproduction only
  • Morphology and methods of reproduction
Darwins finches are an excellent example of
  • Adaptive radiation
  • Seasonal migration
  • Brood parasitism
  • Connecting links
Origin of life occurred in
  • Precambrian
  • Coenozoic
  • Palaeozoic
  • Mesozoic
_________ muscles are found attached to the tail bone of humans.
  • Cardiac
  • Smooth
  • Striped
  • Rudimentary
Which of the following is the most primitive ancestor of man?
  • Homo habilis
  • Homo neanderthalensis
  • Australopithecus
  • Ramapithecus 
Ancestor of man who first stood erect was
  • Australopithecus
  • Cro-magnon
  • Java-ape man
  • Peking man
The reptiles, like dinosaurs were dominant in ________ period.
  • Cretaceous
  • Jurassic
  • Tertiary
  • Triassic
Which of the following is the correct sequence of evolution in vertebrates?
  • Bony fish - amphibians - reptiles - birds
  • Birdsbony fish - amphibians - reptiles
  • Amphibians - reptiles - bony fish - birds
  • Reptiles - birds - bony fish - amphibians
  • Reptiles - birds - amphibians - bony fish
The process in which organisms diversify from a common ancestor is known as ___________.
  • Natural selection
  • Adaptive radiation
  • Vestigial structure
  • Migration
  • Parallel evolution
Structures used for grasping is

481092_10348f72c1674096a2f1b9e05bc8c006.png
  • 1
  • 2
  • 3
  • 4
  • 5
Homo erectus evolved during
  • Pleistocene
  • Miocene
  • Pliocene
  • Holocene
According to Hardy-Weinberg theory, heterozygous individual is
  • $$\displaystyle p$$
  • $$\displaystyle { p }^{ 2 }$$
  • $$\displaystyle 2pq$$
  • $$\displaystyle { q }^{ 2 }$$
  • $$\displaystyle q$$
The frequency of a gene in an ideal population is not affected by ______________.
  • Environmental selective pressure
  • Mutation
  • Random breeding
  • Nonrandom matings
  • Selective emigration
Red streaks are made up of iron oxides on some rocks, formed when iron in ocean reacts with oxygen and settled to the ocean bottom. This chemical and physical process occurs due to
  • Early reducing atmosphere of Earth
  • Evolution of cyanobacteria
  • Symbiosis of photosynthetic bacteria and protists
  • Adaptation of plants to terrestrial environments
  • Metabolic activity of the first heterotrophs
Select the correct pair from the following.
  • Adaptive Radiation - Darwin's Finches
  • Connecting Link - Sewall - Wright effect
  • Genetic drift - Peppered moth
  • Industrial Melanism - Archeopteryx
Which of the following process gives rise to an array of species occupying different niches from an ancestral species?
  • Gradualism
  • Convergent evolution
  • Adaptive radiation
  • Punctuated equilibrium
  • Divergent evolution
The Hardy-Wein-berg equation used to reflect genotypic frequencies in a population, is
                 $${p}^{2}+2pq+{q}^{2}=1$$
Which of the following is indicated by the term $$2pq$$?
  • There are two alleles for that gene in the population
  • There are two genes in the population
  • There are twice as many dominant alleles as recessive alleles in the population
  • There are twice as many heterozygotes as homozygotes in the population
  • There are two separate reproductive combinations that can result in the formation of a heterozygous individual
Which of the following process takes place in the petri dish?
  • Macroevolution
  • Microevolution
  • Adaptive radiation
  • Divergent evolution
  • Speciation
What is true about evolution?
  • Populations evolve while individuals do not evolve.
  • Populations do not evolve while individuals evolve.
  • Populations evolve only when isolated individuals evolve.
  • Populations evolve only through mutations.
All of the following are the requirement for a population to be maintained in Hardy-Weinberg equilibrium through several generations of intermating except
  • Nonrandom mating among individuals
  • No net mutations
  • Large population size
  • Isolation from other populations (no migration into or out of the population)
  • No natural selection occurring
The frequency of the dominant allele in a turtle population living in a local pond showing $$4$$% of recessive phenotype would be
  • $$0.16$$
  • $$0.20$$
  • $$0.40$$
  • $$0.32$$
  • $$0.80$$
Which time period of the geological scale is responsible for mass extinction of Brachiopods?

487236.png
  • Cambrian - Ordovician
  • Silurian - Devonian
  • Permian - Triassic
  • Jurassic - Cretaceous
  • Tertiary - Quaternary
The Hardy-Wein-berg equation used to reflect genotypic frequencies in a population, is
                 $${p}^{2}+2pq+{q}^{2}=1$$
The value of $${p}^{2}$$ reflects
  • The frequency of individuals in the population with the dominant phenotype
  • The frequency of individuals in the population with the homozygous dominant genotype
  • The frequency of the dominant allele in the population
  • The frequency of individuals in the population with the homozygous recessive genotype
  • The frequency of individuals in the population that are heterozygous
Within the squirrel population at City Park, $$16$$% show the recessive phenotype of a curled tail $$\left(tt\right)$$.
The frequency of the dominant allele $$\left(T\right)$$ in the population is
  • $$0.40$$
  • $$0.16$$
  • $$0.26$$
  • $$0.60$$
  • $$0.32$$
The correct order of eras, from most ancient to most recent, along the geological time scale is
  • Paleozoic - precambrian - mesozoic - cenozoic
  • Precambrian - cenozoic - paleozoic - mesozoic
  • Precambrian - mesozoic - paleozoic - cenozoic
  • Precambrian - paleozoic - mesozoic - cenozoic
  • Cenozoic - mesozoic - paleozoic - precambrian
Which of the following statement best describes adaptive radiation?
  • Ability of one species to adapt to only one niche
  • Ability of a species to adapt itself to rapidly changing conditions
  • Evolution from a single ancestral species into several species adapted to various environments
  • Ability of a species to adjust its temperature by radiating heat
  • Advantages of radial symmetry to a stationary species
Which of the following bird's beak is adapted for probing flowers for nectar?
The change in the allele frequencies takes place when evolutionary forces act on a population. Which of the following is not an evolutionary force?
  • Mutations
  • Gene flow
  • Genetic drift
  • Random mating
  • Natural selection
If 60% of the alleles of a gene in population is recessive allele. The percentage of heterozygous individual in this population is
  • 0.16
  • 0.24
  • 0.36
  • 0.48
  • 0.60
Which of the following helps early protobionts to evolve into living cells?
  • A semipermeable membrane and a nucleus
  • Competition for resources and the development of hereditary mechanisms
  • A semipermeable membrane and the ability to catalyze chemical reactions
  • A nucleus and the ability to catalyze chemical reactions
  • A mechanism for growth and a mechanism for asexual reproduction
Both crabs and lobsters are the members of Pleocyemata. Both possess a tail but in the crab, it is very small and not used. This is an example of
  • Convergent evolution
  • Vestigial structure
  • Divergent evolution
  • Genetic fitness
  • Homologous structure
Which of the following is a characteristic of a population in Hardy-Weinberg equilibrium?
  • Founder effect
  • Heterozygote advantage
  • Population bottleneck
  • Random mating
  • Reproductive isolation
Mass extinction of animals is shown at the
500704_2e9164e15909403cac43b42af8c6154f.png
  • End of the Ordovician
  • End of the Silurian
  • End of the Devonian
  • End of the Permian
  • End of the Triassic
Red bands or iron oxide streaks are seen on some rocks which originated from dissolved iron in oceans and settled to the ocean bottom. The reason for the occurrence of chemical and physical process is  _________________.
  • Early reducing atmosphere of Earth
  • Evolution of cyanobacteria
  • Symbiosis of photosynthetic bacteria and protists
  • Adaptation of plants to terrestrial environments
  • Metabolic activity of the first heterotrophs
Which of the following is not a condition required to maintain constant allele frequencies of a gene in a population (Hardy-Weinberg Equilibrium)?
  • Mating is random
  • No natural selection is occurring
  • No mutations occur
  • The population is small
In Hardy-Weinberg equation, the frequency of heterozygous individual is represented by
  • pq
  • $$q^2$$
  • $$p^2$$
  • $$2$$pq
Which of the following is a condition that must be met for a population in Hardy-Weinberg equilibrium?
  • The population in question must be small.
  • Organisms must be free to migrate into or out of the population.
  • New mutations must be introduced to the gene pool at a consistent and unfluctuating rate.
  • Organisms in the population must express no mating preferences.
A heterozygous individual according to Hardy-Weinberg theory is represented by
  • p
  • p$$^2$$
  • 2pq
  • q$$^2$$
  • q
Which of the following fields of study has not contributed directly to evidence for biological evolution?
  • Biochemistry
  • Embryology
  • Geology
  • Quantum physics
The ABO blood typing system in humans is determined by a single locus with three alleles A,B, and O. Worldwide, the frequency of the B allele is 16%.
If blood type is not a factor for either natural or sexual selection and mutations to the locus are negligible, predict the frequency of the B allele in three generations.
  • 0%
  • 3%
  • 16%
  • 40%
A population of humans lives on a fictional isolated island. 75% of the population has purple hair, not found naturally in any other human populations. The purple hair is the result of a single gene locus, for which there are two alleles; purple hair, and non-purple hair (resulting in one of the typical human hair colors, which are determined by other genes).
Which of the following describes a reason the island population fails to meet Hardy-Weinberg equilibrium requirements for purple hair locus?
  • Due to the limited resources available on the island, there is no record of the population ever exceeding 50 people.
  • Neither sex seems to show any mating preference towards hair color, but demonstrating the ability to grill large birds without drying out the breast meat is important to mate selection for both males and females.
  • New people rarely come to the island, and when they do they are unsuccessful in convincing any of the island natives to mate with them.
  • The purple hair does not have any impact on survival.
A fictional population of cliff dwelling birds can be either red or black. Feather color is controlled by a single gene, with black being dominant to red.
A rock slide occurs, killing a portion of the population. The dots in the picture show the distribution of birds on the cliff face, and the birds within the circle were killed in the rock slide.
How does the final population compare to the initial population, and what is the evolutionary explanation for the change?
525232_454ccf12184e4c7d818135dbb157f853.png
  • The frequency of the dominant allele was higher in the final population due to mutations.
  • The frequency of the dominant allele was higher in the final population due to sexual selection.
  • The frequency of the dominant allele was lower in the final population due to genetic drift.
  • The frequency of the dominant allele was lower in the final population due to natural selection.
In a Hardy-Weinberg population, with two alleles (A and a) that are in equilibrium, the frequency of the allele A is 0.What is the percentage of the population that is heterozygous for this allele?
  • 0.32
  • 4
  • 16
  • 32
0:0:1


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Practice Class 12 Medical Biology Quiz Questions and Answers