Insect Life Cycles: Complete and Incomplete Metamorphosis — Answers
Answer sheet with model answers and success criteria for the 4th Grade living things & life cycles worksheet.
Success TutoringWorksheetsAnswer sheet4th Grade · Science · Living Things & Life CyclesInsect Life Cycles: Complete and Incomplete Metamorphosis — Answers
Part A: Two kinds of life cycle
Read the passage. Then circle the best answer.
All insects begin life as an egg, but they grow up in two different ways. Big changes in body shape during a life cycle are called metamorphosis.
Complete metamorphosis has four stages: egg → larva → pupa → adult. The larva looks nothing like the adult. It eats and grows, then forms a pupa. Inside the pupa its body changes completely. Butterflies, moths, beetles, flies, bees and ants all grow this way.
Incomplete metamorphosis has three stages: egg → nymph → adult. A nymph looks like a small adult without full wings. It grows by moulting — shedding its hard outer skin — several times. Grasshoppers, crickets, cockroaches and dragonflies grow this way.
Some young insects live in a different place from the adults. Dragonfly nymphs and mosquito larvae live in water, but the adults fly in the air.
- Aegg → pupa → larva → adult
- Begg → larva → pupa → adult
- Clarva → egg → adult → pupa
- Degg → nymph → adult
Answer: egg → larva → pupa → adult
Complete metamorphosis has four stages: egg, larva, pupa, adult.
- Acaterpillar
- Bnymph
- Ctadpole
- Dmaggot
Answer: caterpillar
The larva of a butterfly or moth is a caterpillar. A maggot is a fly larva.
- Aa butterfly
- Ba beetle
- Ca grasshopper
- Da bee
Answer: a grasshopper
Grasshoppers hatch as nymphs that look like small adults. They have no pupa stage.
- AThe insect lays eggs.
- BThe insect eats lots of leaves.
- CThe insect hatches from an egg.
- DThe insect's body changes into the adult form.
Answer: The insect's body changes into the adult form.
Inside the pupa (a butterfly's chrysalis), the larva's body is rebuilt into the adult.
- AIts hard outer skin cannot stretch as it grows.
- BIt is too cold.
- CIt wants to change color.
- DIt is turning into a pupa.
Answer: Its hard outer skin cannot stretch as it grows.
An insect's outer skeleton is hard. The nymph sheds it so it can grow bigger.
Part B: Stages and names
- butterfly
- fly
- grasshopper
- caterpillar
- nymph
- maggot
Answer: butterfly → caterpillar; fly → maggot; grasshopper → nymph
Answer: chrysalis
Answer: three
Egg, nymph, adult. Also accept: 3.
Answer: The pupa stage (complete metamorphosis also has a larva instead of a nymph).
Part C: True or false?
Write True or False.
Answer: True
The caterpillar is the larva stage; it becomes a butterfly after the pupa stage.
Answer: False
Grasshoppers have no pupa stage. The nymph moults and grows straight into an adult.
Answer: True
Both complete and incomplete metamorphosis begin with an egg.
Part D: Working scientifically: observing a butterfly
Use the class observations to answer.
A class kept a butterfly habitat and recorded what they saw:
Day 1: tiny eggs on a leaf · Day 4: small caterpillars hatched · Day 18: caterpillars hung upside down and formed chrysalises · Day 28: butterflies came out
Answer: 14 days (day 4 to day 18).
Answer: 10 days (day 18 to day 28).
Model answer: It is complete metamorphosis, because it has four stages — egg, larva (caterpillar), pupa (chrysalis) and adult. The caterpillar looked very different from the adult butterfly, and its body changed inside the chrysalis.
Success criteria:
- Identifies complete metamorphosis
- Names the four stages
- Uses evidence from the observations (pupa stage, larva looks different from adult)
Marking tips
- Give credit for correct method even when the final answer slips — the working shows where the thinking went right.
- For open-ended tasks, use the success criteria as a checklist rather than looking for one "right" answer.
- Celebrate what went well first, then pick one thing to work on next.
Great work. Here's what to try next: