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The two kinds of elements present in xylem are:
Xylem in plants is responsible for transport of:
Living cells placed in isotonic solution (0.9% saline) retain their size and shape. This is based on the concept of
Osmosis is the concept that involves in the moment of solutions inside and outside of the cell. If the cell is placed in isotonic solution, the net change will be zero.
Which of the following substances is transported by phloem tissue?
The exudation of xylem sap drops on the edges of leaves is called
Steroid hormones easily pass through the plasma membrane by simple diffusion because they
Steroid hormones are made up of fats and they are not soluble in water. They are hydro phobic in nature. Hence they can easily pass through the plasma membrane by simple diffusion.
Seeds swell when placed in water due to:
Raisins when soaked in water swell up due to imbibition. As a result of absorption or imbibition of water, the size of the raisins increases. The difference in mass between the swollen and dry raisins gives the amount of water imbibed by the raisins.
Which component allows the movement of sugar stored in the roots or stem to the newly growing buds in spring?
In spring, new buds are formed. These buds need more energy to grow than other parts of the plant. This energy comes from the sugar stored in the root or stem tissue to the buds by phloem. Thus, buds need the sugars in springs.
In angiosperms, water is conducted through:
The rate of transpiration increases by an increase in the:
Transpiration is physiological evaporation of water . It is same as evaporation of water from living system. More the temperature more will be evaporation. Hence, transpiration will be more at high temperature.
Root pressure is highest when:
The stomata open when the guard cells are:
The opening and closing of the stomata is controlled by the guard cells. In light, guard cells take up water by osmosis and become turgid. Because their inner walls are rigid they are pulled apart, opening the pore. In darkness, water is lost and the inner walls move together closing the pore.
The loss of water from the aerial parts of the plant during day time is known as:
The loss of water in the form of vapour from living plants, particularly from the aerial parts, is known as transpiration. The process is in principle one of evaporation and diffusion. Loss of water vapour may occur from any part of the plant which is exposed to the air.
An organism’s body has a large proportion of dead cells, have low energy needs, and can use relatively slow transport system. This organism could be :
Plants: Plants do not move. They have a large proportion of dead tissues. Some plants are very tall. So, plants generally have relative slow transport system.
Tissue that transports products of photosynthesis from the leaves where they are synthesized to other parts of the plant, are called:
The phloem is arranged in long, continuous strands called vascular bundles that extend through the roots and stem and reach into the leaves as veins. vascular bundles also contain the xylem, the tissue that carries water and dissolved minerals from the roots to the shoots.