Q. What is the primary driving force for the movement of water in plants?
A.Root pressure
B.Capillary action
C.Transpiration pull
D.Soil moisture
Solution
Transpiration pull is the primary driving force for water movement in plants, created by the evaporation of water from leaf surfaces.
Correct Answer: C — Transpiration pull
Q. What is the primary mechanism by which nutrients are absorbed by plant roots?
A.Active transport
B.Facilitated diffusion
C.Endocytosis
D.Simple diffusion
Solution
Active transport is the primary mechanism for nutrient absorption in plant roots, allowing plants to uptake minerals against their concentration gradient.
Correct Answer: A — Active transport
Q. What is the term for the movement of water from the roots to the leaves?
A.Translocation
B.Transpiration
C.Absorption
D.Evaporation
Solution
Translocation refers to the movement of water and nutrients through the plant, specifically from roots to leaves.
Correct Answer: A — Translocation
Q. Which hormone is primarily involved in regulating stomatal closure?
A.Auxin
B.Gibberellin
C.Abscisic acid
D.Cytokinin
Solution
Abscisic acid is the hormone that signals stomata to close in response to water stress, reducing water loss.
Correct Answer: C — Abscisic acid
Q. Which of the following is a factor that affects the rate of transpiration?
A.Soil pH
B.Humidity
C.Root depth
D.Leaf color
Solution
Humidity affects the rate of transpiration; lower humidity increases transpiration rates due to a greater water vapor gradient.
Correct Answer: B — Humidity
Q. Which process is primarily responsible for the movement of water through xylem?
A.Active transport
B.Diffusion
C.Transpiration
D.Osmosis
Solution
Transpiration creates a negative pressure in the leaves, which pulls water upward through the xylem.
Correct Answer: C — Transpiration
Q. Which structure in plant leaves is primarily responsible for gas exchange?
A.Stomata
B.Cuticle
C.Chloroplasts
D.Xylem vessels
Solution
Stomata are small openings on the leaf surface that allow for gas exchange, including the intake of carbon dioxide and the release of oxygen.
