Formative Practice 4.2 (Form 5 Biology Textbook Exercise and Answer)

Question 1:
State the factors involved in the water and mineral salts pathway from soil to leaves.

Root pressure, capillary action (adhesion and cohesion forces) and transpirational pull.

Question 2:
Give the definition of guttation and state its importance.

Guttation is a secretion of water droplets through a special structure at the end of leaf veins without involving the stomata caused by a high root pressure. Guttation maintains an effective root pressure. Hence, more water and mineral salts is absorbed by the root.

Question 3:
What is the difference between guttation and transpiration?

• Guttation happens at night and early morning whereas transpiration happens on hot and windy days.

• Guttation happens in herbaceous plants whereas transpiration happens in all plants.

• Guttation releases water droplets whereas transpiration released water vapour.

• Guttation happens through a special structure at the end of the leaf veins whereas transpiration happens through stomata.

• Guttation happens when root pressure is high whereas transpiration is controlled by the stomatal opening and closing.

Question 4:
On a hot and windy condition, water absorption by the roots and water transport in the xylem becomes faster.

Do you agree with the statement? Justify.
Agree. The conditions stated causes an increase in evaporation of water through transpiration, thus leading to an increase in transpiration pull.

Leave a Comment