Question

Assertion (A): The early embryos of fish, salamander, tortoise, chick and humans resemble one another closely.

Reason (R): Ontogeny recapitulates phylogeny.

Options

• Both assertion (A) and reason (R) are true, and reason is the correct explanation of assertion.

• Both assertion (A) and reason (R) are true, but reason is not the correct explanation of assertion.

• Assertion (A) is true but reason (R) is false.

• Both assertion (A) and reason (R) are false.

Answer 1

Both assertion (A) and reason (R) are true, and reason is the correct explanation of assertion.

Explanation:

Early vertebrate embryos share features such as pharyngeal clefts, a notochord and a tail-like structure. The recapitulation theory relates developmental stages to ancestral history and is used to explain these embryological similarities.