Q21
Guard cells help in
Correct Answer
Option A
Solution
(a) Guard cells regulate stomatal aperture, controlling transpiration and gas exchange.
Transport in Plants
Q22
Transpiration and root pressure cause water to rise in plants by
Correct Answer
Option A
Solution
(a) Transpiration pulls water up; root pressure pushes water up.
Q23
Stomata in grass leaf are
Correct Answer
Option A
Solution
(a) Grass (monocot) stomata: dumb-bell shaped guard cells.
Q24
Stomatal movement is not affected by
Correct Answer
Option D
Solution
(d) O2 concentration does not directly affect stomatal movement.
Q25
Grass leaves curl inwards during very dry weather. The most appropriate reason is
Correct Answer
Option B
Solution
(b) Bulliform cells lose turgor during water stress, causing leaves to curl/roll.
Q26
Translocation of carbohydrate nutrients usually occurs in the form of
Correct Answer
Option D
Solution
(d) Sucrose is the primary form of carbohydrate translocated in phloem.
Q27
Bidirectional translocation of minerals takes place in
Correct Answer
Option B
Solution
(b) Phloem allows bidirectional (up and down) translocation of minerals and organic solutes.
Q28
The translocation of organic solutes in sieve tube members is supported by
Correct Answer
Option A
Solution
(a) P-proteins (phloem proteins) are structural components supporting sieve tubes.
Q29
The movement of mineral ions into plant root cells as a result of diffusion is called
Correct Answer
Option C
Solution
(c) Passive absorption: movement of ions by diffusion along concentration gradient.
Q30
If cell A has DPD 4 bars and cells B, C, D have OP/TP = 4/4, 10/5, 7/3 bars respectively, water flow will be
Correct Answer
Option C
Solution
(c) DPD: A=4, B=0, C=5, D=4; water flows from lower to higher DPD, so from B (DPD=0) to A, C, D.
Ready for a full NEET mock test?
Timed · full syllabus · instant results
Take a Mock Test →