Transpiration

Question 1

Transpiration stream

Answer 1

The continuous passage of water through a plant from root to leaf is called the transpiration stream.

Question 2

Transpiration

Answer 2

Transpiration is the process by which water is lost by evaporation from the aerial parts of a plant. Most transpiration occurs through tiny pores in the leaf called stomata.

Question 3

Transpiration process

Answer 3

• Water is being used by mesophyll cells for photosynthesis and is also being lost from the leaves by evaporation through stomata which causes water to be drawn up the xylem.
• This transpiration pull causes continuous, thin, tense columns of water to be drawn up the xylem .
• At the same time root hairs spread out from the roots and greatly increase the surface area for absorption.
• Water in the soil enter the cells of the root hairs by osmosis and diffuses through permeable cell walls.
• Water moves from cell to cell by osmosis until it enters the xylem.
Process then repeats.

Question 4

Factors affecting transpiration

Answer 4

Temperature - causes an increase in transpiration.
Humidity- causes a decrease in transpiration.
Wind speed - causes an increase in transpiration.
Light intensity- causes an increase in transpiration.