Review the key concepts, formulae, and examples before starting your quiz.
🔑Concepts
Metamorphosis: The biological process by which an animal physically develops after birth or hatching, involving a conspicuous and relatively abrupt change in the animal's body structure through cell growth and differentiation.
Complete Metamorphosis: A four-stage life cycle consisting of . Insects like butterflies and houseflies undergo this process.
Incomplete Metamorphosis: A three-stage life cycle consisting of . Insects like cockroaches and grasshoppers show this development.
Larva vs. Nymph: A larva (e.g., caterpillar) looks completely different from the adult, while a nymph looks like a smaller, wingless version of the adult.
Molting: The process of shedding the outer skin or exoskeleton periodically to allow for growth, commonly seen in the nymph stage of cockroaches.
Life Cycle of a Frog: A transformation from an aquatic stage to a terrestrial stage. The stages are .
Adaptations in Frogs: Tadpoles use gills for breathing under water and have tails for swimming, whereas adult frogs develop lungs and skin for exchange and legs for hopping.
📐Formulae
💡Examples
Problem 1:
Identify the stage of a butterfly that is often referred to as a 'resting stage' where the body undergoes internal transformation.
Solution:
The Pupa stage (or Chrysalis).
Explanation:
During the stage, the insect is enclosed in a protective covering. Although it appears inactive from the outside, the larval tissues are broken down and rebuilt into the adult body structure.
Problem 2:
A student observes a young organism in a pond that has gills and a long tail but no legs. After a few weeks, it develops lungs and legs. Identify the organism and the process.
Solution:
Organism: Tadpole (Frog); Process: Metamorphosis.
Explanation:
The change from a gill-breathing tadpole to a lung-breathing adult frog involves significant morphological changes. This is a classic example of amphibian metamorphosis, where the organism transitions from an aquatic habitat to a semi-terrestrial one.
Problem 3:
How many stages are there in the life cycle of a cockroach, and what is the middle stage called?
Solution:
There are stages; the middle stage is called the Nymph.
Explanation:
Cockroaches undergo incomplete metamorphosis: . The nymph resembles the adult but lacks wings and functional reproductive organs.