All animals have a life cycle: they are born, grow, reproduce and die. Mammals such as dogs and humans are born alive and drink milk from their mother. Birds hatch from eggs with hard shells.
Some animals change shape completely as they grow. This is called metamorphosis. A butterfly starts as an egg, hatches into a caterpillar, makes a chrysalis, then comes out as an adult butterfly. A frog starts as frogspawn, hatches into a tadpole with a tail and gills, grows legs and lungs, and becomes an adult frog.
Worked example
Which stage comes after the caterpillar in a butterfly's life cycle?
- Egg → caterpillar → ? → adult.
- The caterpillar forms a hard case around itself.
Answer:The next stage is the chrysalis (pupa).
Key words
- life cycle
- the stages of an animal's life
- metamorphosis
- a big change in body shape while growing
- larva
- the young stage of an insect, such as a caterpillar
- pupa
- the resting stage before an adult insect; a chrysalis
Practise this
New questions every time.
NGSS-referenced: 3-LS1-1