Life Cycle Models

Frogs exhibit an amphibian life cycle with metamorphosis from egg to adult. Eggs are laid in water and fertilized externally. Embryos develop into tadpoles, which are aquatic larvae with gills, tail, and specialized feeding structures. During metamorphosis, tadpoles undergo resorption of the tail, development of limbs, lungs, and digestive modifications to transition from herbivorous to carnivorous diet. Hormones such as thyroxine regulate these changes. Understanding the frog life cycle provides insights into developmental biology, hormonal regulation, and adaptation to aquatic and terrestrial environments.

The butterfly undergoes a complete metamorphosis comprising four stages: egg, larva (caterpillar), pupa (chrysalis), and adult. Eggs are laid on host plants, from which larvae hatch. Caterpillars feed voraciously, molting several times while growing. Pupation involves transformation inside the chrysalis, during which larval tissues are broken down and adult structures develop. Finally, the adult butterfly emerges, capable of flight, reproduction, and pollination. Understanding this life cycle is fundamental in entomology, ecology, and conservation biology, and demonstrates biological processes of growth, differentiation, and metamorphosis.