Biology · Science General

Evolution and Biological Adaptation

1,288 Questions

Evolution and biological adaptation focus on natural selection, speciation events, and how organisms adjust to environmental changes over time. These foundational biology concepts appear frequently in general science sections of civil services and school board examinations. Use these questions to study evolutionary theories, ancestral traits, and the fossil record.

Natural selection mechanismsSpeciation event examplesBiological adaptation traitsPanspermia hypothesis conceptsFossil record analysisMate selection theories

Evolution and Biological Adaptation Questions

Multiple choice

Which of the following is not correct?

  1. Cytoskeleton is present in eukaryotic cells and absent in prokaryotic cells.

  2. Endocytosis and exocytosis occur only in eukaryotic cells.

  3. Circular DNA in cytosol only occurs in prokaryotic cells.

  4. First eukaryotic cell on earth were born more than 3 billion years ago.
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

The fossil record shows that earliest eukaryotic cells evolved about 1.5 billion years ago. Details of the evolutionary path from prokaryotes to eukaryotes cannot be deduced from the fossil record alone, but morphological and biochemical comparison of modern organisms has suggested a reasonable sequence of events consistent with the fossil evidence.

Multiple choice

Which of the following do(es) not determine human evolution?

  1. Relationships with other species

  2. Fossil dating

  3. DNA sequence

  4. Skin colour
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

We can determine human evolution by studying the fossils and also by studying the relationships of structure, anatomy, etc. with other species. The similarity and relationships can also be established by studying the DNA sequences of humans and comparing with other species. But skin colour cannot be used for determining human evolution because it has a huge variation in the same species.

Multiple choice

Which of the following options best describes homologous organs?

  1. Organs which are similar in structure, origin and function

  2. Organs which are similar in structure and origin, but different in function

  3. Organs which are similar in function, but different in structure and origin

  4. Organs which are similar in function and structure, but different in origin
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Homologous organs are those which have similar internal structure and origin, but they are differently modified in various organisms to perform the functions that they require, e.g. forelimbs of a man to write; forelimbs of a horse to walk; forelimbs of a bird to fly; and forelimbs of a whale to swim. Thus, only (2) is correct. Option (3) is opposite of homologous organs because organs which are similar in function, but different in structure and origin are called analogous organs, e.g. wings of birds and bats.

Multiple choice

Which of the following could not be explained by Darwin’s Natural Selection Theory?

  1. Presence of Tasmanian wolf only in Tasmania, having become extinct from the Australian mainland

  2. Long neck and long legs of giraffe

  3. Retention of characters of no use or vestigial organs

  4. Growth of numerous young trees below the parent trees and perishment of many of them

Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Natural selection is the gradual process by which heritable biological traits become either more or less common in a population as a function of the effect of inherited traits on the differential reproductive success of organisms interacting with their environment. It is a key mechanism of evolution. The term "natural selection" was popularised by Charles Darwin, who intended it to be compared with artificial selection, now more commonly referred to as selective breeding.

Multiple choice

According to Darwin, the organic evolution is due to

  1. intraspecific competition

  2. interspecific competition

  3. mutation

  4. reduced feeding efficiency in one species due to the presence of interfering species
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

According to Darwinism, competition between two different species is the key factor for organic evolution since it results in divergent evolution.

Multiple choice

Consider the following statements:

(a) Darwin differentiated between somatic and germinal variations. (b) Darwin failed to explain how an animal would evolve from aquatic animals. (c) A number of vestigial organs persisting generation after generation has no explanation according to Darwinism.

Which of the above statements is/are incorrect?

  1. Only (a)

  2. Only (b)

  3. Only (c)

  4. All of the above

  5. None of these
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Statement (a) is incorrect. Darwin did not differentiate between somatic and germinal variations.

Multiple choice

‘Natural selection’ selects individuals who are

  1. most adapted for survival

  2. least adapted for survival

  3. more in number

  4. less in number
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Natural selection refers to the phenomenon where nature selects those organisms which are well adapted. This means that they adjust with the changing environment and survive. Those which are least adapted are unable to survive. 

Multiple choice

What is Darwin's explanation of the way in which evolution occurs?

  1. God determines which species should evolve.

  2. Adaptations enable one species to produce more offspring by natural selection.

  3. Certain species undergo mutations.

  4. The traits used most often persist longer.
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Darwin stated that adaptations enable one species to produce more offspring by natural selection. 

Multiple choice

Which of the following are the examples of analogous organs?

  1. Wings of bird and bat

  2. Forelimbs of man and bat

  3. Forelimbs of man and bird

  4. Forelimbs of frog and lizard
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Analogous organs are the organs which have the same function but are of different origin. Wings of birds and bats are analogous organs.