Plant Transport Pt 2 Xerophytes And Hydrophytes

Question 1

What water conservation features do typical land-dwelling (mesophytic) plants have?

Answer 1

• Waterproofed cuticle
• Stomata that can be opened or closed
• Exchange surfaces that are protected within the leaf to prevent excess evaporation (spongy mesophyll cells)

Question 2

What is a xerophyte?

Answer 2

A xerophyte is a plant adapted to conditions in which there is a lack of water (and therefore it needs to decrease transpiration to try and prevent desiccation).

Example - Marram Grass

Question 3

List the typical xerophytic leaf adaptations.

Answer 3

• Leaf Curvature: The fold creates an area of humid air which decreases the water potential gradient for evaporation and transpiration.
• Reduced Leaf Surface Area: Structures such as spines or needles reduce the area over which transpiration can take place.
• Sunken Stomata: Pits or grooves allow diffusion shells of humid air to build around the stomata, which reduces the water potential gradient and therefore reduces evaporation and transpiration.
• Leaf hairs: Found on the lower surface, these trap a layer of humid air in a diffusion shell and reduce the water potential gradient between the inside and outside of the leaf.
• thick cuticle: helps to reduce evaporation.
• succulent leaves and tissues; store large amounts of water for periods of drought

Question 4

Answer 4

Question 5

Answer 5

Question 6

Answer 6