Grass leaves curl inwards during very dry weather. Select the most appropriate reason from the following
flaccidity of buliform cells
shrinkage of air spaces in spongy mesophyll
tyloses in vessels
closure of stomata
A.
flaccidity of buliform cells
Buliform cells become flaccid due to water loss. This will make the leaves to curl inward to minimise water loss.
Apopalstic movement of water occurs exclusively through the
(i) Intercelluar spaces
(ii) Walls of the cells
(iii) Plasmodesmata
(iv) Cytoplasm
(i), (ii) and (iv) only
(iii) and (iv) only
(i) and (ii) only
(ii) and (iv) only
(ii) and (iv) only
What is the direction of movement of sugars in phloem?
Upward
Downward
Bi-directional
Non-multidirectional
When a molecule moves across a membrane independent of other molecules the process is called
(i) Uniport
(ii) Symport
(iii) Antiport
(i) only
(i) and (ii) only
(i) and (iii) only
(ii) and (iii) only
(ii) and (iii) only
