Animal Life Cycle

1) What Is the Meaning of Life Span? Give Examples.

The period from birth to the death of an organism is called its life span. The lifespans of a few animals are given below—

• Dog: 10-13 years
• Elephant: 60-70 years
• Chimpanzee: 15-30 years
• Lion: 15-16 years
• Parrot: Some species of parrots can live up to 100-120 years, whereas some have a smaller life span of around 20 years.

2) Metamorphosis in Frog Is Controlled by Iodine. Why?

• Metamorphosis requires a hormone called thyroxine, secreted by the thyroid gland.
• Iodine is required for the proper functioning of the thyroid gland so that it can secrete the required amount of thyroxine.

3) How Does the Larva of a Butterfly Survive Without Feeding in the Pupa Stage?

• The larva of a butterfly eats voraciously in the second stage of their life cycle, i.e., caterpillar.
• During this stage, the larva stores food in its body in the form of fat.
• Energy is released in the pupa stage by burning the stored fat.
• It helps the larva to survive without eating in the pupa stage.

4) Why Is Water Essential in the Life Cycle of a Frog?

• The frog is an amphibian, and it lays eggs in water.
• The stages in the lifecycle of a frog cannot be accomplished in the absence of water.
• Also, the prominent feature of its life cycle, i.e., metamorphosis, takes place in water.
• Hence, water plays a crucial role in the life cycle of a frog.

5) Why Do Some Animals Show Metamorphosis?

• In some animals, the offspring born is very different from the adult.
• For instance, the tadpole of the frog has gills, whereas the adult frog has lungs.
• To develop features resembling adults, some animals undergo metamorphosis.