Xerophytic Plants

Question 1

Plants that live in conditions with a plentiful supply of freshwater have leaves with a

Answer 1

short diffusion distance through the stomata and a large surface area provided by the air spaces in the spongy mesophyll

Question 2

Plants that live in conditions with a plentiful supply of freshwater have leaves with a short diffusion distance through the stomata and a large surface area provided by the air spaces in the spongy mesophyll

These factors make them vulnerable to water loss

Xerophytic meaning

Answer 2

A plant that is adapted to live in conditions in which there is either a scarcity of water in the soil, or the atmosphere is dry enough to provoke excessive transpiration, or both.

Question 3

Plants that live in conditions where freshwater is limited have evolved very effective adaptations to conserve water:

Answer 3

Very few stomata
Sunken stomata
Hairs surrounding stomata
Needle-shaped or small leaves
Waxy cuticle

Question 4

Very few stomata

Answer 4

Stomata control a tradeoff for the plant: they allow carbon dioxide in, but they also let precious water escape. A plant that could get enough carbon dioxide with fewer stomata would have an advantage since it would be better able to conserve its water.

Question 5

Waxy cuticle

Answer 5

it acts as a waterproof barrier to evaporation and also the shiny surface reflects heat and so lowers temperature.

Question 6

Needle-shaped or small leaves

Answer 6

This reduces the surface area and hence the evaporating surface. Spines protect the plant from animals, shade it from the sun and also collect moisture.

Question 7

Hairs surrounding stomata

Answer 7

to provide a wind break and reduce air flow, thereby reducing the rate of evaporation.

trap water vapour

Question 8

Sunken stomata

Answer 8

ensure less water loss, thus reduces the rate of transpiration.