Shellfish & crabs
6 free practice questions with explanations
PassNova has 6 free Kids Sea Life practice questions on Shellfish & crabs, each with a clear explanation. Practise them in the browser with instant feedback — 100% free, no sign-up, on any device. Updated for 2026.
Shellfish & crabs: example questions & answers
6 worked examples with answers and explanations below. Practise them in the browser with instant feedback on every answer.
How many legs does a crab have?
- AFour legs
- BTwo legs
- CEight legs plus two claws✓
- DTwenty legs
Answer: A crab has eight walking legs and a pair of claws called pincers at the front.
What does a crab have on the outside of its body to keep it safe?
- ASticky slime
- BSmooth scales
- CSoft fur
- DA hard shell✓
Answer: A crab wears its hard shell on the outside like a suit of armour.
How does a crab usually walk?
- ASideways✓
- BBy hopping
- COn two legs
- DBackwards only
Answer: Crabs are famous for scuttling sideways along the sand and rocks.
A hermit crab keeps itself safe by living inside what?
- AA hole in a tree
- BAn empty seashell✓
- CA bird's nest
- DA cardboard box
Answer: A hermit crab borrows an empty shell to protect its soft body and moves to a bigger one as it grows.
Which of these is a shellfish that makes a shiny pearl inside its shell?
- AA shrimp
- BA jellyfish
- CAn oyster✓
- DA crab
Answer: An oyster can slowly make a smooth, shiny pearl inside its two-part shell.
What are the big front pincers on a crab used for?
- AFlying through the air
- BDigging tunnels in trees
- CCombing its fur
- DGrabbing food and defending itself✓
Answer: A crab uses its strong claws to pick up food and to protect itself.