Question

If heterocysts of blue-green algae are covered then how do they take water by diffusion through it?

Answer 1

Heterocyst is a specialized nitrogen fixing cell formed in some blue green algae in low nitrogen areas. This heterocyst can not perform photosynthesis and the supply of glucose comes from the main vegetative cells. As it does not perform photosynthesis, there is no requirement of water as such for these types of cells. They get the necessary nutrient from the glucose supplied to them.