Xylem in plants does not:
1. conduct material upward from the roots.
2. conduct materials within the dead cells.
3. transport large amounts of sugars and amino acids.
4. have a lower water potential than soil does.

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

Guttation is the result of:

Match List - I with List-II.

Choose the correct answer from the options given below.

Xylem transports air by:
1. the proton pump
2. active transport
3. chemiosmosis
4. air is not transported by xylem normally

The most important problem faced by most plants during flooding is:
1. inability to receive sunlight
2. leaching of nutrients
3. damage to the root system
4. oxygen deprivation

Mangrove plants are able to survive in water logged regions as their pneumatophores have:
1. Stomata
2. Halophytes
3. Parenchyma
4. Lenticels

Water vapor comes out from the plant leaf through the stomatal opening. Through the same stomatal opening, carbon dioxide diffuses into the plant during photosynthesis. Reason out the above statements using one of the following options
1. Both processes cannot happen simultaneously
2. Both processes can happen together because the diffusion coefficient of water and CO₂ is different
3. The above processes happen only during night time
4. One process occurs during day time and the other at night

Which of the following is not required for transpiration?
1. adhesion of water molecules to cellulose.
2. cohesion between water molecules.
3. evaporation of water molecules.
4. active transport through xylem cells.

All the following regarding the cohesion-tension model are true except:
1. Water movement is driven by transpiration.
2. The water potential of atmospheric air is more positive than that for xylem.
3. Cohesion represents the tendency for water molecules to stick together by hydrogen bonds.
4. The physical forces in the capillary-sized xylem cells make it easier to overcome gravity.