Primary 4 · Science · Cycles: Life Cycles
Cycles: Life Cycles questions for Primary 4 Science
10 questions to work through online, 2 of them written out the way the paper asks. Answer and you get the working straight away, then a score at the end. No sign-up, and you can retake it as often as you like.
- Reading a life cycle
- Applying a life cycle
- Comparing two cycles
- Which young resemble adults
- Which stage does the damage
- Frog life cycle
- Breaking a cycle
- Naming a stage
- Counting stages
- Reasoning about stages
Same picture as the question above.
| Insect | Egg | Larva | Pupa | Nymph | Adult |
|---|---|---|---|---|---|
| P | ✓ | ✓ | ✓ | ✗ | ✓ |
| Q | ✓ | ✗ | ✗ | ✓ | ✓ |
Answers and explanations for all 10 questions
Every answer with the reasoning behind it. Worth reading after you have tried the set — or on its own, if you are a parent marking it.
According to the diagram above, which stages of a mosquito live in water?
Answer: egg, larva and pupa
The first three stages — egg, larva and pupa — all develop in water. Only the adult leaves it.
Based on the life cycle shown above, why does emptying containers of standing water reduce the number of mosquitoes?
Answer: It removes the water the first three stages need to develop in.
Egg, larva and pupa all need standing water. Take the water away and the cycle is broken before any adult can form.
Based on the table above, which two statements are correct?
Answer: A and B only
P has egg, larva, pupa and adult — four stages. Q has egg, nymph and adult, and a nymph is a young insect that looks like a small wingless adult.
In which of these does the young look completely different from the adult?
Answer: a butterfly
A caterpillar has no wings, no long legs and a completely different body from the butterfly it becomes. The others all resemble their parents from the start.
Caterpillars strip the leaves off a farmer's cabbages, but the adult butterflies do not. Why does the farmer still try to keep butterflies off the field?
Answer: The butterflies lay the eggs that the caterpillars hatch from.
Keeping the adults away stops the eggs being laid, which stops the caterpillars appearing at all — dealing with the cycle rather than the damage.
Which change happens as a tadpole becomes an adult frog?
Answer: It grows legs and loses its tail.
A tadpole swims with a tail and no legs. As it develops, legs grow and the tail is gradually absorbed until the adult frog can live on land.
Which two of these would break a housefly's life cycle before any adult appears?
Answer: A and B only
Breaking the cycle means stopping a stage before the adult. Covering bins prevents eggs; clearing rotting food starves the larvae.
A young grasshopper looks like a small adult without wings. What is this young stage called?
Answer: nymph
A young insect that resembles a small wingless adult is a nymph.
Look at the life cycle shown in the diagram above. How many stages does it have? (Answer with a number.)
Answer: 4
Egg, larva, pupa and adult make 4 stages.
Why does a caterpillar eat almost constantly while an adult butterfly eats very little?
Answer: The caterpillar has to store enough food to change into an adult inside the pupa.
Inside the pupa the insect is rebuilt completely and cannot feed. All the material for that has to be eaten and stored during the caterpillar stage.