Plant Adaptations and Transpiration Processes

The video tutorial covers the concept of transpiration in plants, focusing on the loss of water vapor from leaves and stems. It discusses factors affecting transpiration, such as light, temperature, humidity, and wind, and explains the transpiration stream, which involves water movement from roots to leaves. The role of hormones like abscisic acid in regulating stomata is highlighted, along with adaptations in xerophytes like cacti to conserve water. The video concludes with practice questions to reinforce learning.

What is the primary function of transpiration in plants?

• To produce energy through photosynthesis

• To facilitate the loss of water vapor

• To protect leaves from herbivores

• To absorb nutrients from the soil

How does increased light intensity affect the rate of transpiration?

• It causes the stomata to close

• It increases the rate of transpiration

• It has no effect on transpiration

• It decreases the rate of transpiration

What happens to the rate of transpiration when humidity is high?

• It increases

• It decreases

• It remains unchanged

• It causes the plant to wilt

Which factor speeds up the rate of transpiration by removing saturated air around the plant?

• Light

• Temperature

• Humidity

• Wind

What is the role of cohesion in the transpiration stream?

• It breaks down water molecules

• It prevents water from evaporating

• It helps water molecules stick together

• It increases the temperature of water

Which hormone is responsible for closing the stomata during water stress?

• Auxin

• Gibberellin

• Abscisic acid

• Indole acetic acid

Why are the stomata located on the underside of leaves?

• To increase photosynthesis

• To reduce water loss

• To absorb more sunlight

• To attract pollinators

What is a key adaptation of xerophytes to conserve water?

• Thin cuticles

• Vertical stems

• Shallow roots

• Broad leaves

How does CAM physiology help xerophytes conserve water?

• By increasing leaf surface area

• By opening stomata at night

• By closing stomata at night

• By opening stomata during the day

What is the purpose of spines instead of leaves in cacti?

• To increase photosynthesis

• To store water

• To reduce water loss

• To attract insects