Miss lee - Xerophytes and Hydrophytes

Question 1

What is a Xerophytes

Answer 1

Xerophytes are plants adapted to living in dry conditions.

They are able to survive in such conditions because of various adaptations which serve to minimise the water loss.
The adaptations include:
-Smaller leaves which reduce the surface area for water loss.
-Both densely packed mesophyll and thick waxy cuticles prevent water loss via evaporation.
-Moreover, xerophytes respond to low water availability by closing the stomata to prevent water loss.
- Apart from this, they contain hairs and pits which serve as a means of trapping moist air, thus reducing the water vapour potential.
-Xerophytes also roll the leaves to reduce the exposure of lower epidermis to the atmosphere, thus trapping air.

Question 2

What are Hydrophytes

Answer 2

Hydrophytes are plants that actually live in water such as water lillies.
As such they need their own adaptations for this environment.

• They have a very thin or absent waxy cuticle as they don’t need to conserve water.
• Many constantly open stomata are found on the upper surfaces of leaves to maximise gas exchange.
• Wide, flat leaves give a large surface area for light absorbtion.
• Air sacs are found in some hydrophytes to enable leaves to stay afloat.
• Many large air spaces to make leaves and stems more buoyant.