Question

Which of the following animals does not undergo metamorphosis?
a. Moth
b. Earthworm
c. Starfish
d. Tunicate

Answer 1

Hint: Metamorphosis is the process of transformation of a larva into an adult. It is the type of indirect development. In earthworms, development of adult is direct. Animals that have larval stage during development show metamorphosis. Metamorphosis includes larva and pupa stage during development of egg into adult. Earthworms do not show larval and pupa stage during their development. Amphibians and insects usually show metamorphosis.

Complete answer:
Development of adults from eggs includes various stages. There are various changes observed in the habits of an animal during normal development of adult from embryonic stage. It is known as metamorphosis. During metamorphosis eggs develop into larva which ultimately develops into adults. It is called indirect development.

During direct development of embryo eggs directly develop into young ones and then the adult larval stage does not include in this type of development.
- Earthworms do not include any larval stage during their development tunicate belong to the category of urochordates. Larva is well developed in these organisms. Larva develops into sessile adults further but advanced features are absent in it.
- Moth comes in the category of insect. They show complete metamorphosis that means eggs develop into larva, larva develop into pupa which develops into adult.
- Starfish belongs to Echinodermata. Larva stage present in it.

From the above information we can say that earthworms do not undergo metamorphosis.
Hence, the correct answer is option (B).

Additional information:
Moth comes in the category of insect. They show complete metamorphosis that means eggs develop into larva, larva develop into pupa which develops into adult.
Starfish belongs to Echinodermata. Larva stage present in it.

Note: Metamorphosis can be complete or incomplete. It is said that humans also show metamorphosis like amphibians, humans have very similar life stages. Insects develop other features like development of wings, stretching their legs and becoming a part of the world. Most of the insects undergo complete metamorphosis.