Transport In Plants(12th Grade > Biology ) Questions and Answers
Explanation:-
Answer: Option D. -> II only:
D
Xylem elements are dead where living protoplasm is absent. This means that a cell membrane or a semipermeable membrane is absent. Hence the movement of water through xylem doesn't involve osmosis. It occurs due to the pressure gradient created by the transpiration pull and the adhesion, cohesion and surface tension properties of water.
All of the other processes mentioned here involves osmosis and changes in turgor pressure.
Explanation:-
Answer: Option D. -> All of the above:
D
Over small distances, substances move by diffusion and cytoplasmic streaming supplemented by active transport. Long distance transport occurs through the vascular system by mass flow.
Explanation:-
Answer: Option C. -> Mycorrhiza – symbiotic association of alga and fungus:
C
In the apoplast pathway water flows outside cell membranes but includes cell walls. In symplast, water enters cells which are interconnected by plasmodesmata.Mycorrhiza is a symbiotic association of fungus and pine (gymnosperms). In guttation, water exudes out of leaves in the liquid form because of root pressure.
Explanation:-
Answer: Option B. -> False:
B
False. Transport of substance against the concentration gradient is impossible without the expenditure of energy. The transport can be done without the usage of energy as long as it is along the concentration gradient.
Explanation:-
Answer: Option A. -> Organic and mineral nutrients undergo multi-directional transport.:
A
Mineral nutrients are primarily absorbed by the roots and transported to different parts of the plant. Whereas organic nutrients based on their need in the plant body get transported in any direction, from the leaves to storage organs and from storage organs to different parts of the plant.
Explanation:-
Answer: Option A. -> Both A & R are true and R explains A:
A
Active transport uses energy to pump molecules against concentration gradient i.e from the region of lower concentration to higher concentration and hence the transport is referred as uphill transport.
Explanation:-
Answer: Option B. -> False:
B
False. Transport of substance against the concentration gradient is impossible without the expenditure of energy. The transport can be done without the usage of energy as long as it is along the concentration gradient.
Explanation:-
Answer: Option A. -> True:
A
Cell system has an optimum temperature maintained for its metabolic activity. This temperature can facilitate optimal kinetic energy for movement of molecules.Thus in aminimal heat energy, smaller molecules can diffuse faster than larger molecules as they require more energy and rate of diffusion becomes slow.
Explanation:-
Answer: Option A. -> ABCDE:
A
Water potential of the atmosphere is more negative than leaf xylem. From theleaf xylem to the root xylem water potentialincreases and soil solution has the maximum water potential.