Puoliintumista

Puoliintumista, also known as metamorphosis, is a biological process by which an animal physically develops after hatching from an egg. This process is characterized by distinct stages of growth and transformation. The term "metamorphosis" comes from the Greek words "meta," meaning "change," and "morph," meaning "form." Metamorphosis is a common feature among insects, amphibians, and some other animals.

In insects, metamorphosis typically occurs in four stages: egg, larva (often called a caterpillar or grub), pupa (chrysalis), and adult. The larva feeds and grows, then enters the pupal stage, where it undergoes significant internal and external changes. During this time, the larva's body breaks down and is rebuilt into the adult form. Finally, the adult insect emerges from the pupa.

Amphibians, such as frogs and salamanders, also undergo metamorphosis. They hatch from eggs as larvae, known as tadpoles, which have gills and a tail. Over time, the tadpole's tail disappears, its gills are replaced by lungs, and its legs develop. This transformation allows the tadpole to live on land and eventually become an adult amphibian.

Metamorphosis is a crucial stage in the life cycle of many animals, enabling them to adapt to different environments and survive. It involves complex biological processes, including cell differentiation, tissue reorganization, and hormonal regulation. The study of metamorphosis provides valuable insights into the mechanisms of development and evolution.