Sudden change occurring in a population

EVOLUTION MCQs for NEET UG BIOLOGY — Mixed difficulty

1 Easy

1 of 339

Understanding +4 | -1

The main point of Darwin’s theory is

View answer and explanation

Correct option: B

Natural selection

Option B is correct because natural selection is the central mechanism in Darwin's theory of evolution.

Solution approach

Correct Answer + Core Reason: Natural selection. Natural selection is the driving force behind Darwin's theory of evolution.

Step-by-Step Solution:

Step 1: Recall the main points of Darwin's theory of evolution.

Step 2: Consider the role of natural selection in driving evolutionary change.

Step 3: Understand that natural selection is the process by which organisms with advantageous traits are more likely to survive and reproduce.

Why other options are wrong:
- Option A: Variation is a prerequisite for natural selection, but not the main point of the theory.
- Option C: Enormous fertility contributes to the struggle for existence, but is not the main point of the theory.
- Option D: Mutation provides new genetic variation, but natural selection acts on this variation.

Key Concepts:
- Natural selection
- Darwin's theory of evolution

Memory Aids:
- Remember that natural selection is the driving force behind Darwin's theory of evolution.

Quick Tips:
- Focus on the role of natural selection in driving evolutionary change.

2 Easy

2 of 339

Understanding +4 | -1

Which one of the following is not a vestigial structure in Homo sapiens?

View answer and explanation

Correct option: B

Epiglottis

Option B (Epiglottis) is correct because the epiglottis is a functional structure that prevents food from entering the trachea.

Solution approach

Correct Answer + Core Reason: Epiglottis. The epiglottis is a functional structure that prevents food from entering the trachea and is not vestigial.

Step-by-Step Solution:

Step 1: Define what a vestigial structure is.

Step 2: Consider the function of each structure listed.

Step 3: Identify the structure that has a current, essential function.

Why other options are wrong:
- Option A (Third molar): Third molars (wisdom teeth) are often impacted and non-functional, making them vestigial in many individuals.
- Option C (Plica semilunaris): The plica semilunaris is a remnant of the nictitating membrane (third eyelid) and is considered vestigial.
- Option D (Pyramidalis muscle): The pyramidalis muscle is a small, triangular muscle in the lower abdomen that is absent in some individuals and has a limited function, making it vestigial.

Key Concepts:
- Vestigial structures
- Human anatomy
- Function of anatomical structures

Memory Aids:
- Remember that the epiglottis is essential for swallowing safely.

Quick Tips:
- Understand the function of different anatomical structures to determine if they are vestigial.

3 Medium

3 of 339

Remembering +4 | -1

The brain capacities of Homo habilis were

View answer and explanation

Correct option: B

650-800cc

Option B (650-800cc) is correct because this is the known brain capacity range for Homo habilis.

Solution approach

Correct Answer + Core Reason: 650-800cc. This is the established brain capacity range for Homo habilis.

Step-by-Step Solution:

Step 1: Recall the characteristics of Homo habilis.

Step 2: Homo habilis is known for having a brain capacity between 650 and 800 cc.

Step 3: Compare the given options with the known brain capacity.

Step 4: Select the option that matches the brain capacity of Homo habilis.

Why other options are wrong:
- Option A (900cc): This brain capacity is larger than that of Homo habilis and is more characteristic of Homo erectus.
- Option C (1400cc): This brain capacity is much larger than that of Homo habilis and is closer to that of Neanderthals or modern humans.
- Option D (1350cc): This brain capacity is also much larger than that of Homo habilis and is not associated with this species.

Key Concepts:
- Human Evolution
- Homo habilis characteristics
- Brain capacity of hominids

Memory Aids:
- Remember "habilis" as "handy man" with a smaller brain than later species.

Quick Tips:
- Memorize the brain capacities of key hominid species to answer such questions quickly.

4 Medium

4 of 339

Analyzing +4 | -1

Assertion (A): In mammals the forelimbs perform different functions.

Reason (R): The forelimbs in different mammals consist of different sets of bones.

View answer and explanation

Correct option: C

If (A) is true but (R) is false

Option C is correct because while forelimbs in mammals perform different functions, they consist of the same basic set of bones, modified for different purposes.

Solution approach

Correct Answer + Core Reason: If (A) is true but (R) is false. Mammalian forelimbs perform different functions, but they have the same basic set of bones.

Step-by-Step Solution:

Step 1: Understand Mammalian Forelimbs: Mammalian forelimbs are adapted for various functions, such as walking, swimming, flying, and grasping.

Step 2: Evaluate Assertion (A): The assertion that in mammals the forelimbs perform different functions is true. For example, a bat's wing, a whale's flipper, and a human's arm all perform different functions.

Step 3: Evaluate Reason (R): The reason states that the forelimbs in different mammals consist of different sets of bones. This is false. Mammalian forelimbs have the same basic set of bones (humerus, radius, ulna, carpals, metacarpals, phalanges), but these bones are modified in shape and size to perform different functions. This is an example of homologous structures.

Step 4: Determine the relationship: Since the assertion is true and the reason is false, the correct answer is C.

Why other options are wrong:
- Option A: The reason is false.
- Option B: The reason is false.
- Option D: The assertion is true.

Key Concepts:
- Homologous Structures
- Adaptation
- Mammalian Anatomy

Memory Aids:
- Homologous: Same bones, different forms.

Quick Tips:
- Remember the basic bone structure of mammalian limbs.

5 Easy

5 of 339

Remembering +4 | -1

Identify the phenomenon in which the members of a species do not interbreed with the members of other species or same species

View answer and explanation

Correct option: D

Reproductive isolation

Option D (Reproductive isolation) is correct because it specifically refers to the inability of members of different species, or even the same species, to interbreed and produce viable, fertile offspring.

Solution approach

Correct Answer + Core Reason: Reproductive isolation. This is the phenomenon where members of different species or even the same species cannot interbreed.

Step-by-Step Solution:

Step 1: Define reproductive isolation: Mechanisms that prevent interbreeding between different species or populations.

Step 2: Consider the other options:
- A: Habitat species - Not a recognized term in this context.
- B: Geographical isolation - Physical separation, but doesn't necessarily prevent interbreeding if brought together.
- C: Temporal isolation - Isolation due to different breeding times, but doesn't necessarily prevent interbreeding if times overlap.

Step 3: Conclude that reproductive isolation is the correct term.

Why other options are wrong:
- Option A: "Habitat species" is not a standard term related to interbreeding.
- Option B: Geographical isolation can contribute to speciation, but it's not the phenomenon of not interbreeding itself.
- Option C: Temporal isolation is a *cause* of reproductive isolation, not the phenomenon itself.

Key Concepts:
- Reproductive Isolation
- Speciation
- Prezygotic Barriers
- Postzygotic Barriers

Memory Aids:
- "Reproductive" refers to breeding; reproductive isolation prevents breeding.

Quick Tips:
- Understand the different types of reproductive isolation (e.g., temporal, behavioral, mechanical).

6 Easy

6 of 339

Analyzing +4 | -1

Assertion: Organic compounds first evolved in earth required for origin of life were protein and nucleic acid.
Reason: All life forms were in water environment only.

View answer and explanation

Correct option: B

If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

Option B (If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion) is correct because while both the assertion about organic compounds and the reason about the water environment are true, the water environment isn't the sole reason for the evolution of organic compounds.

Solution approach

Correct Answer + Core Reason: If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion. Both statements are true, but the water environment is not the direct explanation for the evolution of proteins and nucleic acids.

Step-by-Step Solution:

Step 1: Analyze Assertion: Organic compounds first evolved in Earth required for the origin of life were protein and nucleic acid.

Step 2: Analyze Reason: All life forms were in a water environment only.

Step 3: Evaluate the relationship: Both statements are true, but the water environment is not the direct cause of the evolution of proteins and nucleic acids.

Step 4: Final Answer: If both Assertion and Reason are correct but Reason is not a correct explanation of the Assertion.

Why other options are wrong:
- Option A: The reason is not the correct explanation.
- Option C: Both are true.
- Option D: Both are true.

Key Concepts:
- Origin of life
- Organic compounds
- Water environment

Memory Aids:
- Remember that the water environment was important, but not the sole reason for the evolution of organic compounds.

Quick Tips:
- Consider the different factors that contributed to the origin of life.

7 Medium

7 of 339

Remembering +4 | -1

‘XX’ lived 100000-40000 years ago, in Europe, Asia and Africa. ‘XX’ was short stature, hairy eyebrows, sctreating forehead and large jaws. Identify ‘XX’

View answer and explanation

Correct option: A

Neanderthal man

Option A (Neanderthal man) is correct because the description matches the known characteristics of Neanderthals.

Solution approach

Correct Answer + Core Reason: Neanderthal man. The description matches Neanderthal characteristics.

Step-by-Step Solution:

Step 1: Analyze the given characteristics: The description includes short stature, hairy eyebrows, retreating forehead, and large jaws.

Step 2: Compare with hominin species: These characteristics are typical of Neanderthals.

Step 3: Eliminate other options:
- Homo habilis: Earlier hominin with smaller brain size.
- Cro-magnon man: Early Homo sapiens with more modern features.
- Dryopithecus: An ape ancestor, not a hominin.

Why other options are wrong:
- Option B: Homo habilis is an earlier hominin and doesn't fit the description as well.
- Option C: Cro-magnon man is early Homo sapiens and had more modern features.
- Option D: Dryopithecus is an ape ancestor and doesn't fit the hominin description.

Key Concepts:
- Hominin evolution
- Neanderthals
- Homo sapiens

Memory Aids:
- Neanderthals = Short, stocky, heavy brow

Quick Tips:
- Remember key characteristics of different hominin species.

8 Hard

8 of 339

Remembering +4 | -1

Which of the following is the unit of evolution?

View answer and explanation

Correct option: C

Population

Option C is correct because evolution occurs at the population level, not at the level of individual organisms.

Solution approach

Correct Answer + Core Reason: Population. Evolution is defined as a change in the heritable characteristics of biological populations over successive generations.

Step-by-Step Solution:

Step 1: Define evolution and its scope.

Step 2: Consider that evolution involves changes in allele frequencies within a population over time.

Step 3: Recognize that individual organisms do not evolve; rather, populations evolve as a whole.

Why other options are wrong:
- Option A: A cell is a basic unit of life, but not the unit of evolution.
- Option B: An individual organism does not evolve; rather, populations evolve.
- Option D: A species is a group of populations that can interbreed, but the unit of evolution is the population.

Key Concepts:
- Evolution
- Population genetics

Memory Aids:
- Remember that evolution occurs at the population level, not at the individual level.

Quick Tips:
- Focus on the changes in allele frequencies within a population when considering evolution.

9 Medium

9 of 339

Remembering +4 | -1

Hugo de Vries’s experimental organism was

View answer and explanation

Correct option: D

Evening primrose

Option D is correct because Hugo de Vries conducted his mutation experiments using the evening primrose (Oenothera lamarckiana).

Solution approach

Correct Answer + Core Reason: Evening primrose. Hugo de Vries used the evening primrose in his experiments on mutation.

Step-by-Step Solution:
Step 1: Recall Hugo de Vries's work: He is known for his mutation theory of evolution.
Step 2: Identify the experimental organism: He used the evening primrose (Oenothera lamarckiana).

Why other options are wrong:
- Option A: Fruit flies were used extensively by Thomas Hunt Morgan in his work on genetics.
- Option B: China rose plant is not the organism used by Hugo de Vries.
- Option C: Four O'clock plant is not the organism used by Hugo de Vries.

Key Concepts:
- Hugo de Vries
- Mutation Theory
- Evening Primrose

Memory Aids:
- De Vries = Evening Primrose.

Quick Tips:
- Remember the key scientists and their experimental organisms.

10 Easy

10 of 339

Remembering +4 | -1

In which era, life was absent?

View answer and explanation

Correct option: D

Azoic

Option D (Azoic) is correct because the Azoic era is characterized by the absence of life.

Solution approach

Correct Answer + Core Reason: Azoic. The Azoic era is defined by the absence of life.

Step-by-Step Solution:

Step 1: Understand the question. The question asks about the era when life was absent.

Step 2: Recall the geological eras. The major eras are Azoic, Archaeozoic, Proterozoic, Palaeozoic, Mesozoic, and Cenozoic.

Step 3: Define Azoic era. Azoic era is the earliest part of Earth's history when there was no life.

Step 4: Conclusion. The era when life was absent is the Azoic era.

Why other options are wrong:
- Option A: Archaeozoic era is marked by the beginning of life (primitive life forms).
- Option B: Palaeozoic era is marked by the diversification of marine life and the appearance of land plants and animals.
- Option C: Proterozoic era is marked by the evolution of eukaryotes and multicellular organisms.

Key Concepts:
- Geological time scale
- Azoic era
- Archaeozoic era
- Proterozoic era
- Palaeozoic era

Memory Aids:
- Azoic = "a" (without) + "zoic" (life) = without life

Quick Tips:
- Remember the order of the geological eras to answer such questions.

11 Easy

11 of 339

Understanding +4 | -1

The concept of chemical evolution is based on

View answer and explanation

Correct option: D

Possible origin of life by combination of chemicals under suitable environment conditions

Option D (Possible origin of life by combination of chemicals under suitable environment conditions) is correct because the concept of chemical evolution posits that life arose from the gradual formation of complex organic molecules from simpler inorganic substances in Earth's early environment.

Solution approach

Correct Answer + Core Reason: Chemical evolution is based on the origin of life by combination of chemicals under suitable environmental conditions.

Step-by-Step Solution:

Step 1: Chemical evolution proposes that life arose from non-living matter through a series of chemical reactions.

Step 2: These reactions involved the formation of organic molecules from inorganic substances.

Step 3: Suitable environmental conditions, such as the presence of water, energy sources (e.g., lightning, UV radiation), and a reducing atmosphere, were necessary for these reactions to occur.

Why other options are wrong:
- Option A: Crystallization of chemicals is a physical process and does not explain the origin of life.
- Option B: Interaction of water, air, and clay under intense heat is a possible scenario, but it doesn't encompass the full scope of chemical evolution, which involves the formation of complex organic molecules.
- Option C: Effect of solar radiation on chemicals is a factor, but it's only one aspect of the broader process of chemical evolution.

Key Concepts:
- Chemical evolution
- Abiogenesis
- Origin of life

Memory Aids:
- Chemicals + Environment = Life

Quick Tips:
- The Miller-Urey experiment is a classic example of simulating chemical evolution in the lab.

12 Medium

12 of 339

Analyzing +4 | -1

Read the following statements and find out incorrect statements:

A) Alfred Wallace worked in Malay Archipelago

B) Anteater and numbat show convergent evolution

C) Branching descent and natural selection are key concepts of lamarck's theory of evolution

D) Marsupial mole and Marsupial mouse consider as examples of placental mammals

View answer and explanation

Correct option: A

C and D

Option A (C and D) is correct because branching descent and natural selection are key concepts of Darwin's theory, not Lamarck's, and marsupial moles and mice are not considered placental mammals.

Solution approach

Correct Answer + Core Reason: C and D. Branching descent and natural selection are Darwinian concepts, and marsupial moles and mice are not placental mammals.

Step-by-Step Solution:

Step 1: Evaluate statement A: Alfred Wallace worked in Malay Archipelago. This is a correct statement.

Step 2: Evaluate statement B: Anteater and numbat show convergent evolution. This is a correct statement.

Step 3: Evaluate statement C: Branching descent and natural selection are key concepts of lamarck's theory of evolution. This is incorrect; these are key concepts of Darwin's theory.

Step 4: Evaluate statement D: Marsupial mole and Marsupial mouse consider as examples of placental mammals. This is incorrect; they are marsupials, not placental mammals.

Step 5: Identify the incorrect statements: C and D.

Why other options are wrong:
- Option B: A is correct, so this option is incorrect.
- Option C: B is correct, so this option is incorrect.
- Option D: A and B are correct, so this option is incorrect.

Key Concepts:
- Darwin's theory of evolution
- Lamarck's theory of evolution
- Convergent evolution
- Marsupials
- Placental mammals

Memory Aids:
- Darwin = Natural Selection.
- Marsupials != Placentals.

Quick Tips:
- Know the key differences between Darwin's and Lamarck's theories.

13 Easy

13 of 339

Remembering +4 | -1

The Mesozoic era is also called as the golden age of the

View answer and explanation

Correct option: B

Reptiles

Option B (Reptiles) is correct because the Mesozoic era is widely known as the age of reptiles, characterized by their dominance.

Solution approach

Correct Answer + Core Reason: Reptiles. The Mesozoic era is known as the age of reptiles.

Step-by-Step Solution:
Step 1: Recall the major life forms that dominated each geological era.
Step 2: The Mesozoic era is characterized by the dominance of reptiles, including dinosaurs.
Step 3: Therefore, the Mesozoic era is also called the golden age of reptiles.

Why other options are wrong:
- Option A: Amphibians were more prominent in the Paleozoic era.
- Option C: Mammals became dominant in the Cenozoic era.
- Option D: Birds evolved during the Mesozoic era but did not dominate it.

Key Concepts:
- Geological time scale
- Mesozoic era
- Dominant life forms in different eras

Memory Aids:
- Mesozoic = Reptiles (Think "Meso-Reptiles")

Quick Tips:
- Memorize the dominant life forms for each major geological era.

14 Easy

14 of 339

Understanding +4 | -1

Evolution is

View answer and explanation

Correct option: B

Progeny with modifications

Option B is correct because evolution is the process of change in the heritable characteristics of biological populations over successive generations, leading to progeny with modifications.

Solution approach

Correct Answer + Core Reason: Progeny with modifications. Evolution results in offspring that differ from their ancestors due to accumulated changes over time.

Step-by-Step Solution:

Step 1: Define evolution and its scope.

Step 2: Consider that evolution involves changes in the heritable characteristics of biological populations over successive generations.

Step 3: Understand that these changes lead to modifications in the progeny compared to their ancestors.

Why other options are wrong:
- Option A: Evolution is not necessarily a sudden change; it can be gradual.
- Option C: Evolution is a continuous process, not discontinuous.
- Option D: Only option B is correct.

Key Concepts:
- Evolution
- Heritability
- Adaptation

Memory Aids:
- Remember that evolution leads to progeny with modifications over time.

Quick Tips:
- Focus on the changes in heritable characteristics over successive generations when considering evolution.

15 Hard

15 of 339

Understanding +4 | -1

Assertion: The modern horse evolved during
pliocene epoch.

Reason: It arose from eohippus.

View answer and explanation

Correct option: D

If both Assertion and Reason are false

Option D (If both Assertion and Reason are false) is correct because the modern horse evolved during the Pleistocene epoch, not the Pliocene, and it evolved from a series of ancestors, not directly from Eohippus.

Solution approach

Correct Answer + Core Reason: Both Assertion and Reason are false.

Step-by-Step Solution:

Step 1: The assertion states that the modern horse evolved during the Pliocene epoch, which is incorrect. The modern horse evolved during the Pleistocene epoch.

Step 2: The reason states that it arose from Eohippus, which is also incorrect. The modern horse evolved through a series of intermediate ancestors from Eohippus, not directly from it.

Step 3: Therefore, both the assertion and the reason are false.

Why other options are wrong:
- Option A: Both Assertion and Reason are not true, so this option is incorrect.
- Option B: Both Assertion and Reason are not true, so this option is incorrect.
- Option C: Assertion is not true, so this option is incorrect.

Key Concepts:
- Evolution of the horse
- Geological epochs
- Ancestral relationships

Memory Aids:
- Modern horse = Pleistocene

Quick Tips:
- Remember the evolutionary lineage of the horse and the corresponding geological epochs.

16 Hard

16 of 339

Remembering +4 | -1

What is the important example of genetic drift?

View answer and explanation

Correct option: C

Both 1 and 2

Option C (Both 1 and 2) is correct because both the founder effect and bottleneck effect are important examples of genetic drift.

Solution approach

Correct Answer + Core Reason: Both 1 and 2. Both founder effect and bottleneck effect are examples of genetic drift.

Step-by-Step Solution:

Step 1: Define the terms.

Step 2: Founder effect occurs when a small group of individuals establishes a new population, leading to a different allele frequency than the original population.

Step 3: Bottleneck effect occurs when a population's size is drastically reduced, leading to a loss of genetic diversity and a change in allele frequencies.

Step 4: Industrial melanism is an example of natural selection, not genetic drift.

Step 5: Therefore, both founder effect and bottleneck effect are examples of genetic drift.

Why other options are wrong:
- Option A: Founder effect is only one example of genetic drift, not the only one.
- Option B: Bottleneck effect is only one example of genetic drift, not the only one.
- Option D: Industrial melanism is an example of natural selection, not genetic drift.

Key Concepts:
- Genetic drift
- Founder effect
- Bottleneck effect

Memory Aids:
- Founder = New population
- Bottleneck = Population reduction

Quick Tips:
- Remember that both founder and bottleneck effects reduce genetic diversity.

17 Medium

17 of 339

Analyzing +4 | -1

Lemur is placental mammal. If it exhibits convergent evolution with an australian marsupial, it should be :

View answer and explanation

Correct option: B

Spotted cuscus

Option B is correct because the spotted cuscus is the Australian marsupial that exhibits convergent evolution with the placental mammal lemur.

Solution approach

Correct Answer + Core Reason: Spotted cuscus. Lemur and Spotted cuscus exhibit convergent evolution.

Step-by-Step Solution:

Step 1: Recall the concept of convergent evolution.

Step 2: Identify the Australian marsupial that occupies a similar ecological niche as the Lemur.

Step 3: The Spotted cuscus is the marsupial counterpart to the placental Lemur.

Why other options are wrong:
- Option A: Anteater is convergent with Numbat.
- Option C: Tasmanian tiger cat is convergent with Bobcat or Wolf.
- Option D: Flying phallanger is convergent with Sugar Glider.

Key Concepts:
- Convergent Evolution
- Ecological Niche
- Placental Mammals
- Australian Marsupials

Memory Aids:
- Convergent evolution: different species evolve similar traits independently.

Quick Tips:
- Understand the ecological niches and how different species adapt to them.

18 Easy

18 of 339

Analyzing +4 | -1

From the options given below showing convergent evolution between placental mammals and Australian marsupials, which is incorrectly matched?

View answer and explanation

Correct option: B

Placental Mammals - Flying phalanger, Australian Marsupials - Flying squirrel

Option B is incorrectly matched. Flying phalanger is a marsupial, and sugar glider is its placental mammal counterpart, not flying squirrel.

Solution approach

Correct Answer + Core Reason: Placental Mammals - Flying phalanger, Australian Marsupials - Flying squirrel. This pair is incorrect because the placental counterpart of the Australian marsupial Flying Phalanger is the Sugar Glider.

Step-by-Step Solution:

Step 1: Review the concept of convergent evolution: different species evolve similar traits due to similar environmental pressures.

Step 2: Evaluate each option:
- A: Lemur - Spotted cuscus (Correct match)
- B: Flying phalanger - Flying squirrel (Incorrect match. Sugar glider is the placental counterpart of Flying Phalanger)
- C: Anteater - Numbat (Correct match)
- D: Bobcat - Tasmanian tiger cat (Correct match)

Step 3: Identify the incorrect match: Option B is incorrect.

Why other options are wrong:
- Option A: Lemur and Spotted cuscus are a correct example of convergent evolution.
- Option C: Anteater and Numbat are a correct example of convergent evolution.
- Option D: Bobcat and Tasmanian tiger cat are a correct example of convergent evolution.

Key Concepts:
- Convergent Evolution
- Placental Mammals
- Australian Marsupials

Memory Aids:
- Convergent evolution: species evolve similar traits independently.

Quick Tips:
- Understand the ecological niches and how different species adapt to them.

19 Hard

19 of 339

Understanding +4 | -1

Read the following three statements (a) – (c) and mark the correct option.

(a) The thorns of Bougainvillea and tendrils in cucurbita represent divergent evolution.

(b) The similarity in the eyes of octopus and monkeys is the result of convergent evolution.

(c) The potato and sweet potato are the examples of homology.

View answer and explanation

Correct option: A

(a) and (b)

Option A ((a) and (b)) is correct because thorns and tendrils are homologous, and octopus and monkey eyes are analogous.

Solution approach

Correct Answer + Core Reason: (a) and (b). Thorns and tendrils are homologous, and octopus and monkey eyes are analogous.

Step-by-Step Solution:

Step 1: Analyze statement (a): The thorns of Bougainvillea and tendrils in cucurbita are modifications of the same structure (axillary bud), indicating divergent evolution from a common ancestor. Thus, statement (a) is correct.

Step 2: Analyze statement (b): The similarity in the eyes of octopus and monkeys is due to convergent evolution, where similar environmental pressures lead to similar structures in unrelated organisms. Thus, statement (b) is correct.

Step 3: Analyze statement (c): Potato and sweet potato are analogous structures (modified stems and roots, respectively) that perform similar functions (storage). Thus, statement (c) is incorrect.

Why other options are wrong:
- Option B: Statement (c) is incorrect.
- Option C: Statement (c) is incorrect.
- Option D: Statement (c) is incorrect.

Key Concepts:
- Homologous Structures
- Analogous Structures
- Convergent Evolution
- Divergent Evolution

Memory Aids:
- Homologous = Same origin.
- Analogous = Similar function.

Quick Tips:
- Distinguish between homologous and analogous structures.

20 Hard

20 of 339

Analyzing +4 | -1

Assertion : Cro-magnon man has more
intelligence than the man of present time.

Reason : He is regarded as most recent ancestor
of today's man.

View answer and explanation

Correct option: B

If both Assertion and Reason are true but Reason
is not the correct explanation of Assertion

Option B is correct. While Cro-Magnon man was intelligent and is a recent ancestor, there's no definitive evidence they were *more* intelligent than modern humans, and ancestry doesn't directly equate to intelligence.

Solution approach

Correct Answer + Core Reason: If both Assertion and Reason are true but Reason is not the correct explanation of Assertion. Cro-Magnon intelligence is debatable, and recent ancestry doesn't determine intelligence.

Step-by-Step Solution:
Step 1: Analyze the assertion: Cro-magnon man has more intelligence than the man of present time. This is debatable and not definitively proven.
Step 2: Analyze the reason: He is regarded as most recent ancestor of today's man. This is true.
Step 3: Determine the relationship: Being a recent ancestor doesn't automatically mean greater intelligence.
Step 4: Conclude: The reason doesn't explain the assertion.

Why other options are wrong:
- Option A: The reason is not a correct explanation of the assertion.
- Option C: The assertion is debatable, not definitively true.
- Option D: The reason is true.

Key Concepts:
- Human Evolution
- Cro-Magnon Man
- Intelligence

Memory Aids:
- Ancestry doesn't directly determine intelligence.

Quick Tips:
- Be critical of claims about intelligence in extinct hominids.

21 Medium

21 of 339

Remembering +4 | -1

Select the wrong pair

View answer and explanation

Correct option: B

Spallanzani – Approve abiogenesis

Option B (Spallanzani – Approve abiogenesis) is the wrong pair because Spallanzani disproved abiogenesis.

Solution approach

Correct Answer + Core Reason: Spallanzani did not approve abiogenesis; he disproved it.

Step-by-Step Solution:

Step 1: The question asks to identify the incorrect pairing of a scientist and their contribution to the understanding of the origin of life.

Step 2: Analyze each pair:
- Oparin proposed the concept of probionts.
- Haldane suggested the \"hot dilute soup\" theory.
- Fox is known for his work on microspheres (proteinoids), which are similar to coacervates.
- Spallanzani conducted experiments that refuted the theory of spontaneous generation (abiogenesis).

Step 3: Therefore, the incorrect pair is Spallanzani – Approve abiogenesis.

Why other options are wrong:
- Option A: Oparin – Probiont is a correct pairing.
- Option C: Haldane – Hot dilute soup is a correct pairing.
- Option D: Fox – Coacervates is a correct pairing.

Key Concepts:
- Abiogenesis
- Biogenesis
- Contributions of scientists to the origin of life theories

Memory Aids:
- Spallanzani's experiments with sealed flasks disproved spontaneous generation.

Quick Tips:
- Remember the key experiments and theories associated with each scientist.

22 Easy

22 of 339

Remembering +4 | -1

The concept of natural selection in evolution was proposed by

View answer and explanation

Correct option: A

Charles Robert Darwin

Option A is correct because Charles Robert Darwin proposed the concept of natural selection as the driving force of evolution.

Solution approach

Correct Answer + Core Reason: Charles Robert Darwin. Darwin proposed the concept of natural selection.

Step-by-Step Solution:

Step 1: Recall the key figures in the history of evolutionary thought.

Step 2: Darwin is credited with the theory of natural selection.

Why other options are wrong:
- Option B: August Weismann proposed the germ plasm theory.
- Option C: Hugo de Vries proposed the mutation theory of evolution.
- Option D: Jean Baptiste Lamarck proposed the theory of inheritance of acquired characteristics.

Key Concepts:
- Natural Selection
- Darwin's Theory
- Evolutionary Biology

Memory Aids:
- Darwin = Natural Selection.

Quick Tips:
- Remember the key scientists and their contributions to evolutionary theory.

23 Hard

23 of 339

Remembering +4 | -1

The first life form originated

View answer and explanation

Correct option: C

In water

Option C (In water) is correct because the first life forms are believed to have originated in aquatic environments.

Solution approach

Correct Answer + Core Reason: In water. The first life form originated in water.

Step-by-Step Solution:
Step 1: Recall the conditions necessary for the origin of life.
Step 2: The early Earth's atmosphere was reducing, and the oceans provided a stable environment for the formation of organic molecules and the first cells.

Why other options are wrong:
- Option A: On land, the early Earth's conditions were too harsh for the origin of life.
- Option B: In air, the early Earth's atmosphere lacked a protective ozone layer.
- Option D: All of these is incorrect because only water provided the necessary conditions.

Key Concepts:
- Origin of life
- Early Earth conditions

Memory Aids:
- Water = Life (Think "Water - Where Life Began")

Quick Tips:
- Remember the importance of water for the origin of life.

24 Medium

24 of 339

Understanding +4 | -1

The process by which different type of finches were evolved in Galapagos islands is

View answer and explanation

Correct option: A

Adaptive radiation

Option A (Adaptive radiation) is correct because Darwin's finches are a classic example of a species diversifying to fill different ecological niches.

Solution approach

Correct Answer + Core Reason: Adaptive radiation. Darwin's finches are a prime example of this.

Step-by-Step Solution:

Step 1: Define adaptive radiation: The evolutionary diversification of a single lineage into a variety of forms that occupy different ecological niches.

Step 2: Apply to Darwin's finches: The finches on the Galapagos Islands evolved different beak shapes to exploit different food sources.

Why other options are wrong:
- Option B: Geographic similarity is not a process of evolution.
- Option C: Geographic dissimilarity could contribute to speciation, but doesn't describe the process of finch evolution.
- Option D: Unadaptive radiation is not a recognized term.

Key Concepts:
- Adaptive Radiation
- Darwin's Finches

Memory Aids:
- Adaptive = Adapting to different niches.

Quick Tips:
- Darwin's finches are the classic example of adaptive radiation.

25 Medium

25 of 339

Remembering +4 | -1

Choose the correct statements
I. Law of embryonic development was given by Von Baer
II. Recapitulation theory was proposed by Haeckel
III. Haeckel theory states that ‘Ontogeny repeats phylogeny’
IV. Haeckel theory and biogenetic law were proposed by the same person
The correct combination is

View answer and explanation

Correct option: D

I, II, III and IV

Option D (I, II, III and IV) is correct because all the statements are accurate: Von Baer proposed the law of embryonic development, Haeckel proposed the recapitulation theory, Haeckel's theory states 'Ontogeny repeats phylogeny', and Haeckel proposed both the theory and the biogenetic law.

Solution approach

Correct Answer + Core Reason: I, II, III and IV. All the statements are correct regarding embryonic development and recapitulation theory.

Step-by-Step Solution:

Step 1: Evaluate each statement:
- I. Law of embryonic development was given by Von Baer: Correct.
- II. Recapitulation theory was proposed by Haeckel: Correct.
- III. Haeckel theory states that ‘Ontogeny repeats phylogeny’: Correct.
- IV. Haeckel theory and biogenetic law were proposed by the same person: Correct.

Step 2: Conclusion: All statements are correct.

Why other options are wrong:
- Option A: Incorrect because statements III and IV are also correct.
- Option B: Incorrect because statements I and IV are also correct.
- Option C: Incorrect because statements II and IV are also correct.

Key Concepts:
- Embryonic development
- Recapitulation theory
- Von Baer's law
- Haeckel's biogenetic law

Memory Aids:
- Remember Von Baer's and Haeckel's contributions to embryology.

Quick Tips:
- Carefully evaluate each statement for accuracy.

26 Hard

26 of 339

Understanding +4 | -1

Genetic erosion is due to

View answer and explanation

Correct option: D

All the above

Option D (All the above) is correct because deforestation, shifting cultivation, and adopting genetically uniform varieties all contribute to the loss of genetic diversity, which is genetic erosion.

Solution approach

Correct Answer + Core Reason: All the above. All listed factors reduce genetic diversity.

Step-by-Step Solution:

Step 1: Define Genetic erosion.

Step 2: Genetic erosion is the loss of genetic diversity within a species or population.

Step 3: Deforestation reduces the habitat and population size, leading to a loss of genetic diversity.

Step 4: Shifting cultivation can lead to habitat fragmentation and loss of local varieties.

Step 5: Adopting genetically uniform varieties reduces the overall genetic diversity of crops.

Step 6: Therefore, all the listed factors contribute to genetic erosion.

Why other options are wrong:
- Option A: Deforestation alone contributes to genetic erosion, but it's not the only factor.
- Option B: Shifting cultivation alone contributes to genetic erosion, but it's not the only factor.
- Option C: Adopting genetically uniform varieties alone contributes to genetic erosion, but it's not the only factor.

Key Concepts:
- Genetic erosion
- Genetic diversity
- Deforestation
- Shifting cultivation
- Genetically uniform varieties

Memory Aids:
- Remember that anything that reduces genetic diversity contributes to genetic erosion.

Quick Tips:
- Consider the impact of different agricultural practices on genetic diversity.

27 Medium

27 of 339

Remembering +4 | -1

Which type of growth living organism undergoes?

View answer and explanation

Correct option: D

Intussusception

Option D is correct because living organisms grow through intussusception, which is internal growth by adding new material within.

Solution approach

Correct Answer + Core Reason: Intussusception. Living organisms grow by intussusception, which is growth from within.

Step-by-Step Solution:
Step 1: Define Intussusception: Growth by the addition of new particles between existing particles.

Why other options are wrong:
- Option A: Reversible growth is not a characteristic of living organisms.
- Option B: Apical growth refers to growth at the tips or ends, like in plants, but not the general growth mechanism of all living organisms.
- Option C: Accretion is growth by external addition, like the formation of a pearl, not internal growth.

Key Concepts:
- Intussusception
- Growth in Living Organisms

Memory Aids:
- Intussusception = \"Internal Growth.\"

Quick Tips:
- Remember that living organisms grow from within.

28 Hard

28 of 339

Understanding +4 | -1

Which one of the following is the example of evolution by anthropogenic action :

View answer and explanation

Correct option: A

Antibiotics resistance microbes

Option A (Antibiotics resistance microbes) is correct because the development of antibiotic resistance in microbes is a direct result of human use of antibiotics, which is an anthropogenic action.

Solution approach

Correct Answer + Core Reason: Antibiotics resistance microbes. This is a direct result of human actions.

Step-by-Step Solution:

Step 1: Define evolution by anthropogenic action.

Step 2: Evolution by anthropogenic action is evolutionary change driven by human activities.

Step 3: The overuse and misuse of antibiotics by humans has created a strong selection pressure for antibiotic-resistant microbes to evolve.

Step 4: Microbes that are resistant to antibiotics are more likely to survive and reproduce, leading to an increase in their population.

Step 5: Therefore, antibiotic resistance in microbes is an example of evolution by anthropogenic action.

Why other options are wrong:
- Option B: Marsupial radiation is an example of adaptive radiation, but it is not primarily driven by human activities.
- Option C: Adaptive radiation is a general process of diversification, but it is not necessarily caused by human activities.
- Option D: Only option A is a direct example of anthropogenic action.

Key Concepts:
- Evolution by anthropogenic action
- Antibiotic resistance
- Natural selection

Memory Aids:
- Remember that human actions can have significant evolutionary consequences for other organisms.

Quick Tips:
- Consider the role of human activities in driving evolutionary change.

29 Easy

29 of 339

Understanding +4 | -1

Homologous organs indicate the

View answer and explanation

Correct option: C

Common descendent

Option C (Common descendent) is correct because homologous organs are structures that share a common ancestry, indicating descent from a common ancestor.

Solution approach

Correct Answer + Core Reason: Homologous organs indicate a common descendent.

Step-by-Step Solution:

Step 1: Homologous organs are structures in different species that have a similar underlying anatomy due to shared ancestry.

Step 2: The presence of homologous organs suggests that these species evolved from a common ancestor that possessed the same basic structure.

Step 3: Over time, the structure may have been modified in different lineages to perform different functions, but the underlying similarity remains.

Why other options are wrong:
- Option A: Convergent evolution results in analogous organs, not homologous organs.
- Option B: Parallel evolution is when similar traits evolve independently in closely related lineages, but homologous organs are a direct result of common ancestry.
- Option D: Natural selection is the mechanism that drives evolutionary change, but homologous organs are the result of shared ancestry and subsequent modification.

Key Concepts:
- Homologous organs
- Common descent
- Evolution

Memory Aids:
- Homologous = Common Ancestry

Quick Tips:
- Look for underlying structural similarities when identifying homologous organs.

30 Medium

30 of 339

Analyzing +4 | -1

Read the following statements and find out incorrect statements:
A) Organs which have different origin but have similar function are analogous organs.
B) Wings of butterflies and birds represents analogous organs.
C) Vertebrates hearts and vertebrates brains represents analogous organs.
D) Analogous organs are based on emoryology and physiology.

View answer and explanation

Correct option: D

C and D

Option D is correct because vertebrate hearts and brains are homologous, not analogous, and analogous organs are based on evolutionary adaptation, not embryology and physiology.

Solution approach

Correct Answer + Core Reason: C and D. Vertebrate hearts and brains are homologous, and analogous organs are based on evolutionary adaptation, not embryology and physiology.

Step-by-Step Solution:

Step 1: Define Analogous Organs: Analogous organs are organs that have different origins but perform similar functions. They arise due to convergent evolution.

Step 2: Define Homologous Organs: Homologous organs are organs that have a similar origin and structure, but may have different functions. They arise due to divergent evolution.

Step 3: Evaluate Statement A: Organs which have different origin but have similar function are analogous organs. This is correct.

Step 4: Evaluate Statement B: Wings of butterflies and birds represents analogous organs. This is correct.

Step 5: Evaluate Statement C: Vertebrates hearts and vertebrates brains represents analogous organs. This is incorrect. Vertebrate hearts and brains are homologous organs because they share a common ancestry and developmental origin.

Step 6: Evaluate Statement D: Analogous organs are based on emoryology and physiology. This is incorrect. Analogous organs are based on convergent evolution and adaptation to similar environments, not embryology and physiology.

Why other options are wrong:
- Option A: Statement A is correct.
- Option B: Statement B is correct.

Key Concepts:
- Analogous Organs
- Homologous Organs
- Convergent Evolution
- Divergent Evolution

Memory Aids:
- Analogous: Act alike, different ancestry.
- Homologous: Same ancestry, different action (potentially).

Quick Tips:
- Distinguish between homologous and analogous organs.

Your Progress

Evolution practice · Mixed difficulty

Explore Other Chapters in BIOLOGY

Key Takeaways

Continue Your Practice

Your practice