The humidity of rainforests is largely due to
The evolution of C4 plants is probably one of the strategies to
(1) Maximize oxygen availability
(2) Maximize Carbon dioxide availability
(3) Minimize water loss
(4) Both B and C
C4 plants are …….as efficient as C3 plants in term of making sugar and lose only ….. of the water in comparison.
(1) Half, double
(2) Twice, half
(3) One fourth, one third
(4) Twice, one third
Most of the minerals are absorbed through active transport because
(1) Minerals are charged particles
(2) Minerals are insoluble in lipid bilayer
(3) The amount of mineral is less in soil
(4) All of these
Which of the following statements is not correct?
(1) Some ions also move in epidermal cells passively
(2) The active uptake of ions is partly responsible for the water potential gradient in the roots.
(3) Uptake of water by the roots is through osmosis
(4) Transport proteins of pericycle are control points where a plant adjusts the quantity and types of solute which will cross the cell membrane
What is the chief sink of mineral elements in plants?
(1) Growing regions of the plant
(2) Enlarged cells
(4) Root hair
The most readily mobilised elements from older dying leaves are
(4) All of these
Which of the following is a part of structure and is not remobilised?
Which of the following is incorrect statement?
(1) An analysis of xylem exudate suggests that some of the nitrogen travels as inorganic ions and much of it is carried in the organic form as amino acids
(2) Small amount of P and S is also carried as inorganic compounds in xylem exudate
(3) There is exchange of material between xylem and phloem
(4) Xylem transports inorganic nutrients while phloem transports organic materials, this observation was proved wrong by the analysis of xylem exudate
The source and sink may be reversed
(1) Depending on the season
(2) Depending on the plant's needs
(3) Depending on the phloem type
(4) Both A and B