All Free Biology MCQs with Answers

• A. 32o F
• B. 46oC
• C. 313K
• D. 37oC

Explanation: The optimum temperature for enzymes in the human body is 37ºC, which is crucial for maintaining the proper enzymatic activity necessary…

• A. A friend of mine is coming to visit next week.
• B. The friend of mine is coming to visit next week.
• C. Friend of mine is coming to visit next week.
• D. A friend of me is coming to visit next week.

Explanation: The correct answer is A. A friend of mine is coming to visit next week.

• A. Change in an individual
• B. Change in species over generations
• C. Modification in a single organism
• D. No change in population

Explanation: Evolution is defined as the change in heritable characteristics of biological populations over successive generations, not changes within…

• A. Appendix
• B. Skeleton of whale
• C. Pelvic in man
• D. Leg bone in snakes

Explanation: For instance, the skeletons of whales and some snakes retain vestiges of the pelvis and leg bones of walking ancestors, (Fig.

• A. All organisms show resemblances
• B. The organisms do not show resemblances
• C. The organisms show resemblances but later change
• D. None of the above

Explanation: Explanation for this question will be added soon

• A. Appendix
• B. Coccyx
• C. Wisdom Teeth
• D. Thumb

Explanation: The correct answer is Option D: Thumb. The thumb is not a vestigial organ as it plays a vital role in the dexterity and functionality of…

• A. Adaptations
• B. Polymorphism
• C. Specilaization
• D. Niches

Explanation: Niches refer to the role or position that a species occupies in its ecosystem.

• A. Similarity in characteristics due to shared ancestry
• B. Similarity in function due to acquired characteristics
• C. Study of similar structures regardless of origin
• D. Structures with different functions but similar appearances

Explanation: Homology is a fundamental concept in evolutionary biology that refers to similarities in characteristics due to shared ancestry.

• A. Offspring according to the resources available
• B. Offspring to create resources
• C. To create resources
• D. More offspring than supported

Explanation: According to the 'theory of natural selection', organisms produce more offsprings, than those who can survive i.e.

• A. Appendix
• B. Coccyx
• C. Both Options A and B are correct
• D. None of these options is correct

Explanation: Structures that have no apparent function and appear to be residual parts from a past ancestor are called vestigial structures.

• A. Similarity in characteristics resulting from common ancestors
• B. Similarity in function from acquired characteristics
• C. Study of different organs but with similar functions
• D. Study of similar organs but with different functions

Explanation: By definition, homology is similarity which results from shared ancestry: when similarity of a feature arises because organisms in two…

• A. More offspring than supported
• B. Less offspring than supported
• C. Offspring according to the resources available
• D. Offspring to create resources

Explanation: According to theory of natural selection, those organisms whose inherited characterstics fit them best to their enviroment are likely to…

• A. Origin of life
• B. How organs extinct
• C. How do new species arise?
• D. How do organisms form?

Explanation: Darwin's theory mainly focuses on how new species arise. His theory of evolution by natural selection states that individuals with…

• A. Homo neanderthalensis
• B. Lemuroidea
• C. Dromaeosaums
• D. Pan troglodytes

Explanation: Chimpanzees (Pan troglodytes) and bonobos (Pan paniscus) are both our evolutionary closest living relatives.

• A. Darwin's natural selection
• B. Lamarck's theory
• C. Hardy-Weinberg's principle
• D. None of these options are correct

Explanation: Option A: This is the correct option, Darwin suggested that populations of individual species become better adapted to their environments…

• A. Convergent evolution
• B. Divergent evolution
• C. Natural selecting
• D. Common ancestory

Explanation: Convergent evolution is the independent evolution of similar features in species of different periods in time.

• 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 doesn't apply here

Explanation: One of the assumptions of the Hardy-Weinberg principle is that there is random mating among the individuals of species.

• 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= 1 represents the Hardy-Weinberg principle; where p is the dominant allele,q is the recessive allele.

• A. Inbreeding
• B. Outbreeding
• C. Breeding
• D. None of these

Explanation: Mating is the process in which animals interact by sexual intercourse. When they do not breed within their relatives, we call it…

• A. The organism's ability to attain resources while in competition with other organisms of its species
• B. The organism's ability to attract the most mates
• C. The organism's health
• D. The ability of an organism to contribute its genes to future generations

Explanation: In terms of evolution, fitness is a measure of how well an organism is able to survive and reproduce in its environment.