Topic 3 - Exchange In Plants

Question 1

How do plants prevent water loss?

Answer 1

• stomata: (tiny pores on the leaves that regulate gas exchange), guard cells open and close based on water availability
• waxy cuticle: waterproof layer on leaves to reduce evaporation
• Reduced stomatal density: some plants have fewer stomata to minimise water loss

Question 2

What adaptions do Xerophytes have?

Answer 2

Sunken stomata to trap moist air, reducing the diffusion gradient for water loss
Rolled leaves and hairs on the surface to reduce transpiration
Thick waxy cuticles to minimise water loss
Stomata only open at night