Question

A type of metamorphosis in insects with four developments stages i.e., eggs, larva, pupa and adult is
a. Hemimetabolous
b. Paurometabolous
c. Holometabolous
d. Ametabolous

Answer 1

Hint: Metamorphosis is a natural progression by which a creature actually matures after birth or hatching, involving an obvious and comparatively sudden change in the animal's body structure for the period of cell growth and differentiation. Some insects, fish, amphibians, tunicates, etc go through metamorphosis. It is habitually accompanied by an alteration of nutrition source or behavior.

Complete answer:
> A kind of metamorphosis in insects with four distinct developmental stages i.e, eggs, larva, pupa, and adult is holometabolous. It is a type of insect development that involves four life stages and it is also called complete metamorphosis. This category of metamorphosis takes place in the majority species of insects, involving bees, wasps, butterflies, moths, and ants. Holometabolism is a synapomorphic characteristic of every insect in the Endopterygota order.

> Hemimetabolism or incomplete metamorphosis is the form of growth of certain insects that involves three dissimilar stages: the egg, nymph, and the adult stage, or imago.

> Paurometabolous is the development of slow metamorphosis. In this type of development, immature stages look like small adults, and characteristically have exterior wing buds.

> Ametabolous insects appear from eggs into immatures of virtually the same shape as the adults.

Hence, the correct answer is option (C).

Note: In insects, growth and metamorphosis are managed by hormones created by endocrine glands near the front of the body. Neurosecretory cells in an insect's brain exude a hormone, the prothoracicotropic hormone (PTTH) that triggers prothoracic glands, which emit a second hormone, typically ecdysone, which persuades ecdysis. PTTH also excites the corpora allata, a retrocerebral organ, to manufacture juvenile hormones, which stops the growth of adult characteristics during ecdysis.