- Water will move from the root hair through cortex to
xylem, if the water potentials (ψw) are
Root hair Cortex Xylem
(a) 0 +1 +
(b) +2 +1 0
(c) -2 -1 0
(d) 0.5 -1 -
- match column-I with column-II and select the correct
option from the codes given below.
Column-I Column-II
a. Vein ending (i)Transpiration
B. Necessary evil (ii)Osmosis
c. Semi-permeable
membrane
(iii)Transpiration pull
D. cohesion and adhesion (iv)Guttation
E. Stomata closure (v)aBa
(a) a-(iv), B-(i), c-(iii), D-(ii), E-(v)
(b) a-(iv), B-(i), c-(ii), D-(iii), E-(v)
(c) a-(iii), B-(v), c-(i), D-(ii), E-(iv)
(d) a-(i), B-(ii), c-(iii), D-(iv), E-(v)
- The given diagram a potato plant consuming food of old
tubers (assume). Which route would be taken by most of
the food at this time?
Vegetative bud (7)
New tuber
Old tuber
Main stem
5
6
2
3
1
4
(a) 1 → 4 → 2 → 3 (b) 7 → 5 → 2 → 3
(c) 1 → 4 → 5 → 7 (d) 6 → 5 → 4 → 3
- cause of guttation and bleeding is
(a) development of absorption lag
(b) –ve root pressure early in the morning
(c) +ve root pressure
(d) high transpiration rate.
38. Which of the following is a wrong statement?
(a) movement of water in plant is always unidirectional
but translocation of sucrose may be bi-directional due
to variable source and sink relation.
(b) Sugar from mesophylls of leaf → companion cells
→ sieve tubes is translocated as sucrose by mass
flow hypothesis, passively.
(c) Newly formed root hair absorbs capillary water for
the first time by imbibition.
(d) Despite the absence of heart and circulatory system
in plants, the flow of water upwards through xylem
in plants can be achieved at fairly high rates, upto
15 meters per hours.
39. a cell is kept in hypotonic solution, after sometime its
(a) OP ↓ and ψs ↑ (b) ψw ↑ and DPD ↓
(c) ψp and TP both ↑ (d) all of the above.
40. Which of the following statements are true?
(i) In guard cells of dicots cellulose microfibrils are
arranged tangentially.
(ii) Osmosis is a diffusion of weaker solution into
concentrated solution, when two solutions were
separated by semi-permeable membrane.
(iii) Plasma membrane is differentially permeable
membrane.
(iv) In a flaccid cell ψw = ψs.
(v) If a solution is applied with pressure from outside its
ψw decreases.
(a) (iii), (iv) and (v) (b) (iv) and (v)
(c) (iii) and (v) (d) (i), (iii), (iv) and (v)
41. arrange the events of opening of stomata in correct
sequence and choose the correct option accordingly.
I. Lowering of ψw of guard cells.
II. Decline in guard cell solute.
III. rise of potassium ion level in guard cells.
IV. Guard cells absorb water from neighbouring
epidermal cells.
V. Guard cells become flaccid.
VI. Guard cells swells and make a pore between them.
(a) III, I, IV, V (b) I, II, III, IV, V, VI
(c) III, I, IV, VI (d) III, I, IV, VI, II, V
42. a fresh twig, having flower and buds, is kept in minute
amount of salt containing water. It remains fresh for a
longer period due to
(a) exosmosis
(b) absorption of small amount of water
(c) electrolyte balance
(d) decrease in transpiration rate
