What seems to be the most valid statement about root pressure?

1. It is the positive pressure responsible for transport of water most commonly.

2. It may provide a considerable push to the water column during transport.

3. It may help re establish the broken water columns during transpiration

4. Its effect is most observable during mid day

A structural attribute of guard cells that aid in its effective functioning is

1. Large cell size

2. Radial micellation in walls

3. Thick walls

4. All of the above

Not an aid to water absorption is

1. The high surface area of roots

2. High water potential of root hair cells

3. Thin cellulosic walls of root hair zone

4. Low concentration of solutes in the soil

The water is free to move between the cells except through the

1. xylem

2. epidermis

3. endodermis

4. pericycle

Continuity of protoplasm in sieve elements is maintained through

1. Cytoplasmic strands

2. P proteins

3. Vacuoles

4. Walls

Which is not an advantage of transpiration.

1. Maintains shape of cells by keeping them turgid

2. Cools down plant surfaces by evaporative cooling

3. Transports minerals.

4. None of the above.

One of the following is not a pre-requisite for transpiration?

1. high Vapour pressure deficit of atmosphere

2. Low atmospheric humidity

3.High soil water potential 

4. Sunny weather

A manifestation of root pressure is

1. Guttation

2. transpiration

3. Cohesion

4. Negative hydrostatic pressure

What is not a part of symplast?

1. Cell membrane

2. Cell wall

3. Tonoplast

4. Plasmodesmata

Mass flow seems to be the prominent mode of transport during

1. Translocation of organic solutes within phloem.

2. traslocation of water and minerals in xylem

3. Apolplastic movement of water in plants

4. All of the above