Q. No.Which of the following facilitates opening of stomatal aperture?
| 1. | Decrease in turgidity of guard cells |
| 2. | Radial orientation of cellulose microfibrils in the cell wall of guard cells |
| 3. | Longitudinal orientation of cellulose microfibrils in the cell wall of guard cells |
| 4. | Contraction of outer wall of guard cells |
The water potential of pure water is:
1. Less than zero
2. More than zero but less than one
3. More than one
4. Zero
Root pressure develops due to?
1. Active absorption
2. Low osmotic potential in Soil
3. Passive absorption
4. Increase in transpiration
A column of water within xylem vessels of tall trees does not break under its weight because of?
1. Dissolved sugar in water
2. Tensile strength of water
3. Lignification of xylem vessels
4. Positive root pressure
Transpiration and root pressure cause water to rise in plants by:
2. pulling and pushing it, respectively
3. pushing it upward
4. pushing and pulling it, respectively
Which one of the following is correctly matched?
1. Passive transport of nutrients-ATP
2. Apoplast- Plasmodesmata
3. Potassium- Readily mobilized
4. Bakanae of rice seedlings-F Skoog
| 1. | Calcium | 2. | Potassium |
| 3. | Sulphur | 4. | Phosphorus |
Xylem translocates:
1. Water, minerals salts, some nitrogen and hormones
2. Water only
3. Water and mineral salts only
4. Water, mineral and some organic nitrogen only
What is the direction of movement of sugars in phloem?
1. Bi-directional
2. Non-multidirectional
3. Upward
4. Downward
The main difference between active and passive transport across cell membrane is :
| 1. | passive transport is non-selective whereas active transport is selective |
| 2. | passive transport requires a concentration gradient across a biological membrane whereas active transport requires energy to move solutes. |
| 3. | passive transport is confined to anionic carrier proteins whereas active transport is confined to cationic channel. |
| 4. | active transport occurs more rapidly than passive |
© 2025 GoodEd Technologies Pvt. Ltd.