SECTION B: Answer any 2 questions. (a) What is transpiration? (ii) List the environmental factors that affect the rate of transpiration. (b) How is the process of transpiration important to plants? (c) Using a potometer, describe how the rate of transpiration can be measured.

Here are the answers to question 4:

a) (i) Define Seed dispersal.
Seed dispersal is the process by which seeds are moved away from the parent plant. This helps reduce competition for resources and allows plants to colonize new areas.

a) (ii) Define Gestation.
Gestation is the period of development of an embryo or fetus inside the mother's womb, from conception to birth.

b) State the agents of seed dispersal.
The main agents of seed dispersal are wind, water, animals (including birds, mammals, and insects), and explosive mechanisms (self-dispersal by the plant itself).

c) Differentiate between insect and wind pollinated flowers.

• Insect-pollinated flowers: Typically large, brightly colored, scented, and produce nectar to attract insects. Their pollen grains are often sticky and spiky to attach to insects. Stigmas are usually small and sticky.
• Wind-pollinated flowers: Usually small, dull-colored, unscented, and do not produce nectar. They produce large quantities of light, smooth pollen grains that are easily carried by wind. Stigmas are often large, feathery, and exposed to catch airborne pollen.

d) How is the human embryo protected?
The human embryo is protected within the mother's uterus, which is a muscular organ providing a safe environment. It is surrounded by the amniotic sac, which contains amniotic fluid that cushions the embryo against physical shocks and maintains a stable temperature. The placenta also acts as a barrier against some harmful substances while allowing nutrient and waste exchange.