What is the term for the development process of insects that includes stages from egg to larva to pupa to adult?

The term that describes the development process of insects from egg to larva to pupa to adult is known as metamorphosis. This biological process involves several distinct life stages, each characterized by significant changes in form and function. During metamorphosis, an organism transforms from one developmental stage to another, which is particularly evident in insects.

In the case of insects that undergo complete metamorphosis, such as butterflies and beetles, the transformation involves a dramatic reorganization of the body's structure. For instance, the pupa stage is a resting stage where the larva undergoes significant changes to emerge as a fully formed adult. Metamorphosis is essential for various reasons, including specialization for different ecological niches and strategies for survival.

The other terms listed refer to different biological processes. Eclosion refers specifically to the hatching of an insect from its egg and does not encompass the entire life cycle. Diapause relates to a period of suspended development in response to environmental conditions, allowing the insect to survive unfavorable conditions without progressing through its life cycle. Instar refers to the specific developmental stage of the larva between molts, but it does not convey the entire transition through all stages of an insect's life. Thus, metamorphosis is the correct