Water will be absorbed by root hair when :
In plants, water transport mineral salts through special tubes called xylem. Plants have root hairs on their primary and secondary roots. Plants absorb water and mineral salts from the soil with the help of root hairs. They absorb water by the process of osmosis. Osmosis is the movement of water molecules (solutes) from a lower concentration solution to a higher concentration solution through a semi permeable membrane. So when concentration of solutes in the cell sap is high, water is absorbed by root hair.
Which one of the following is connected with transport of water in plants?
If the cut end of a tree is put in eosin solution
The principal pathways by which water is translocated in angiosperms is :
The carbohydrate synthesized in the leaves are transported through sieve tubes most commonly in the form of
Which of the following contributes most to transport of water from the ground to the leaves of a tall tree?
Water molecules have high cohesion and adhesion forces acting between them thus, a continuous column of water is formed in the xylem. Transpiration i.e., evaporation of water molecules from the cells of the leaf creates a suction force (transpiration pull) which pulls water from xylem cells. To maintain the continuous water column due to cohesion forces water is absorbed from the soil.
Due to low atmospheric pressure the rate of transpiration will
Transpiration is the loss of water from leaves in the form of vapour. There are some factors that affect the transpiration such as temperature, concentration of carbon dioxide, humidity, and atmospheric pressure. The reduction of atmospheric pressure reduces the density of the external atmosphere. This allows more rapid diffusion of water. The plants growing on hills show the higher rate of transpiration because of low atmospheric pressure and thus they develop xerophytes characters. Thus, option A is correct and other options are wrong.
The transpiration in plants will be lowest
Transpiration is loss of water in vapour form through stomata. Rate of transpiration depends on a number of factors, like carbon dioxide concentration, temperature, light, humidity etc. The most important factor which governs rate of transpiration is the vapour pressure gradient, which exists between leaf mesophyll and atmosphere. Thus, more the humidity lesser the rate of transpiration and vice versa.
Rate of transpiration in a dorsiventral leaf is
Two equal pieces of cobalt chloride paper are dried and placed one on the upper surface and the other on the lower surface of dorsiventral leaves. They are firmly held in place by pieces of cellotapes or glass slides. After a few minutes the cohalt chloride paper shows change in colour from blue to pink. The time taken for the cobalt chloride paper on the upper surface of the leaf to turn pink is much longer than for the under surface. Thus, it proves that the rate of transpiration is greater from the under surface of dorsiventral leaves.
Which of the following is not a function of transpiration?
Rate of transpiration slows down when plant
Rate of transpiration slows down when the non-rigid parts of the plant loses its rigidity and is called wilting of plant.
Maximum transpiration occurs in :
Transpiration occurs through the stomatal openings present on the leaves of plants. About 80% to 90% of water is lost through transpiration. Maximum transpiration occurs in mesophyte. In mesophytic plants, stomata are present on both surface of leaves. In hydrophytic plants, stomata are present only on the upper surface. Thus, the correct answer is option A.
Transpiration stream is continued in plants due to :
Stomata are pores in the leaf that allow gas exchange where water vapor leaves the plant and carbon dioxide enters. Special cells called guard cells control each pore's opening or closing. When stomata are open, transpiration rates increase; when they are closed, transpiration rates decrease.
Transpiration in plants take place through
We feel cool near a banyan tree during summer because of :
The big banyan tree leaves transpire. It loses a lot of water during summer by transpiration. The transpired water vapour stays around the tree. This makes the area cooler. This makes us feel cool near a banyan tree during summer.
Water movement against gravity is due to :
It happened so because there is a frequent lossof water from the leaves by transpiration due to which a transpirational pull is developed in the leaves which pull the water against the force of gravity.
The instrument used to measure transpiration is :
A potometer sometimes known as a transpirometer, is a device used for measuring the rate of water uptake of a leafy shoot.
The factors which affects the rate of transpiration is :
The rate of transpiration increases when :
The rate of transpiration can be affected by: light intensity, air movement, temperature and humidity.
Role of transpiration is :
Transpiration plays a vital role in the body of the plants, some of them are : It helps it to transport water and minerals towards the leaves from the roots in the upward direction against the gravitational pull It cools down the plant during summers It removes excess water Also when water is eliminated from the plant it urges the roots to pull more water and along with them minerals are also absorbed with is beneficial for the plant.