Certified Crop Advisor Practice Exam

Which life stage characterizes insects with complete metamorphosis?

1. Egg, nymph, adult

2. Egg, larva, pupa, adult

3. Egg, larva, adult

4. Nymph, pupa, adult

The correct answer is: Egg, larva, pupa, adult

Insects that undergo complete metamorphosis progress through four distinct life stages: egg, larva, pupa, and adult. This process is characterized by significant changes in morphology and behavior at each stage, particularly during the transition from the larval to the pupal stage and finally to the adult stage. The egg stage is the initial phase where fertilized eggs are laid. After hatching, the larval stage emerges, which is often very different in appearance and behavior from the adult insect. This larval stage is primarily focused on feeding and growth. Following this, the insect enters the pupal stage, a period of transformation where the larva undergoes a remarkable change, reorganizing its body structure to develop into the adult form. Finally, the adult stage represents the mature form of the insect, capable of reproduction. This life cycle is distinct from incomplete metamorphosis, where insects develop through three stages: egg, nymph, and adult, without a pupal phase. By understanding the complete metamorphosis cycle, one can better grasp the developmental complexities and ecological roles of insects at different life stages.