Question

during day time daytime root pressure is not effective for transport of water in plants give reason ​

Answer 1

Answer:

Root pressure is the transverse osmotic pressure within the cells of a root system that causes sap to rise through a plant stem to the leaves.

Explanation:

Root pressure occurs in the xylem of some vascular plants when the soil moisture level is high either at night or when transpiration is low during the day. When transpiration is high, xylem sap is usually under tension, rather than under pressure, due to transpirational pull. At night in some plants, root pressure causes guttation or exudation of drops of xylem sap from the tips or edges of leaves. Root pressure is studied by removing the shoot of a plant near the soil level. Xylem sap will exude from the cut stem for hours or days due to root pressure. If a pressure gauge is attached to the cut stem, the root pressure can be measured.

Answer 2

During the daytime, transpiration is the major activity taking place. Transpiration is the loss of water from the aerial parts of the plant.

The water which is lost through stomata due to transpiration, is replaces by water from xylem vessels in the leaf. In fact, evaporation of water molecules from the cells of a leaf creates a suction which pulls water from the xylem cells of roots.

ADVANTAGES OF TRANSPIRATION;

- it helps in absorption and upward movement of water and minerals dissolved in it from roots to the leaves.

- it helps in temperature regulation