Plant Transport and Physiology

 The main function of the xylem is to carry water and mineral salts upward from the root to different parts of shoots.

Cutin deposition reduces the rate of surface transpiration.

The cell wall of cork contains a fatty acid called suberin which makes it impermeable.

Cell wall is not permeable to macromolecules like starch.

 All of the above options are correct.

Sucrose is transferred into the phloem tissue using energy from ATP. This increases the osmotic pressure of the tissue, causing water to move into it. This pressure moves the material in the phloem to tissues which have less pressure.

Water absorption through roots can be increased by keeping the plants under the fan.

Water is transported xylem in plants whereas food is transported through phloem. Stomata are small pores on leaves through which water is lost in the form of water vapor. Root hairs are present on the roots and they help in water absorption from soil.

The root hair increase the surface area of the root for the absorption of water and mineral nutrients dissolved in water. The root hair is in contact with the water present between the soil particles.

Opening and closure of the stomata pore is mediated by changes in the turgor pressure of the two guard cells. The turgor pressure of guard cells is controlled by movements of large quantities of ions and sugars into and out of the guard cells

Root pressure pulls the water level up and excess water absorbed during water logged condition along with some salt, is given out through hydathodes in leaves which is guttation.

Foliar feeding is a technique of feeding plants by applying liquid fertiliser directly to their leaves. Plants are able to absorb essential elements through their leaves. The absorption takes place through their stomata and also through their epidermis. Transport is usually faster through the stomata, but total absorption may be as great through the epidermis. Plants are also able to absorb nutrients through their bark.

Insects affect crop plants by sucking food and water from plant bodies, cutting roots, stems and leaves of plants, and also by getting into fruits and destroying them.

Capillary water is held in the soil pores against gravity and is the primary source of water available for plant root absorption. Gravitational water drains away, while hygroscopic and combined water are held too tightly by soil particles for plants to extract.

Transpiration is the biological process where water is lost as vapor from the aerial parts of plants, primarily through the stomata.