61. Which one option does not involve osmosis ?
A. Water passing from one xylem element to the other above it.
B. Water passing from soil to root hair
C. Water passing into mesophyll cell from xylem
D. Water passing from root hair cell to cortical cell
Answer : Option B
62. A bottle filled with previously moistened mustard seeds and water was screw capped tightly and kept in a corner. It blew up suddenly after about half an hour. The phenomenon involved is
63. When concentration of solutes is low in the soil, absorption of water is
64. Guard cells differ from epidermal cells in having.
65. Wilting in plants occurs when
A. Phloem is blocked
B. Xylem is removed / blocked
C. Pith is removed
D. A few leaves are removed
Answer : Option B
66. Guttation is the process of elimination of water from plants through
67. What is the action spectrum of transpiration ?
A. Green and ultraviolet
B. Orange and red
C. Blue and far red
D. Blue and red
Answer : Option A
68. Stomata open during day time because the guard cells
A. Produce osmotically active sugars or organic acids
B. Are thin walled
C. Are bean shaped
D. Have to help in gaseous exchange
Answer : Option D
69. Stomatal opening is under the control of
70. Maximum transpiration takes place from