Habitats. The aquatic environment
Answers are for parents and teachers.
1
Sort into plankton, nekton or benthos: lobster, sardine, daphnia, mussel, dolphin, fish eggs.
Lobster, mussel – benthos; sardine, dolphin – nekton; daphnia, fish eggs – plankton.
2
Why is a fish’s swim bladder important in water?
It changes the fish’s density and keeps it suspended at the needed depth.
3
Write three differences between a water plant and a land plant.
Weak mechanical tissue and roots; developed aerenchyma; thin leaves.
4
Why are cold polar seas often richer in plankton than warm tropical seas? Explain using the properties of water.
Cold water dissolves more oxygen and carbon dioxide, and mixing of water layers brings minerals up from the bottom; so phytoplankton and the zooplankton feeding on it thrive.