B3.1 Exchange systems in plants Flashcards
1
Q
Carbon dioxide enters the leaves by…
A
…diffusion
2
Q
What are most of the water and mineral ions absorbed by?
A
The roots
3
Q
How is the surface are of the roots increased?
A
Root hairs
4
Q
How is the surface area of leaves increased? (2 things)
A
- Flattened shape
- Internal air spaces
5
Q
Why do plants have stomata?
A
To obtain CO2 from the atmosphere and remove O2 in respiration
6
Q
Where do plants mainly lose water vapour from?
A
The stomata on the leaves
7
Q
When and why do the stomata close?
A
- When plants lose water faster than it is replaced by the roots
- To prevent wilting
8
Q
What do hot, dry and windy conditions do to the rate of transpiration (evaporation)?
A
Transpiration takes place more quickly
9
Q
What do guard cells do to the stomata?
A
- Open and close them
- Control the size of the stomata
