Planarian is the common name for several genera of flatworms. When a planarian is cut in half, each half eventually grows back into a complete worm. Which of the following does this process most resemble?

Question

A.
asexual reproduction of a single-celled organism

B.
sexual reproduction of a single-celled organism

C.
sexual reproduction in which identical twins are produced

D.
asexual reproduction in which a mutation has occurred

Answer 1

The process by which a planarian can regenerate and grow back into a complete worm after being cut in half most resembles:

A. asexual reproduction of a single-celled organism.

This is because the regeneration process is a form of asexual reproduction, where an organism can create a complete individual from a part of itself. In this case, each half of the planarian effectively regenerates into a whole organism, similar to how some single-celled organisms can reproduce asexually by splitting into two.