Tag: transpiration

Quizzes (10) Questions (96)

Questions Related to transpiration

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Exudation of xylem sap on cutting of a shoot is due to

  1. Guttation

  2. Root pressure

  3. Transpiration

  4. None of these
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

When a well-watered shoot is cut near the base, xylem sap often exudes out due to positive hydrostatic pressure built up in the roots, known as root pressure. Guttation involves the loss of liquid water through hydathodes, and transpiration creates negative pressure (tension), not positive exudation.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

State whether the following statement is true or false. If false rewrite the correct form of the statement by changing the last word.
Exudation of sap from the injured parts of a plant is called guttation.

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The statement is correct; the exudation of sap from injured parts is indeed referred to as guttation in many biological contexts.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Water drops present on leaf margins of Tropaeolum, balsam and grasses in early morning are due to

  1. Guttation

  2. Dew

  3. Osmosis

  4. Transpiration
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Guttation is the loss of water in liquid form through hydathodes. Guttation is usually seen under environmental conditions when transpiration is low and soil is well watered. It occurs under the influence of positive root pressure. Water droplets present on leaf margins of some plants in the early morning is not due drops but the water that has oozed out from xylem tracheids. 

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Guttation drops can be differentiated from dew drops

  1. By taste

  2. As dew drops will be seen

  3. As guttation drops will be restricted on the margins of the leaf

  4. All of the above
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Guttation is the loss of water in liquid form through hydathodes. Guttation is usually seen under environmental conditions when transpiration is low and soil is well watered. It occurs under the influence of positive root pressure. Water droplets present on leaf margins of some plants in the early morning is not due drops but the water that has oozed out from xylem tracheids. Xylem tracheids contain dissolved minerals in the water. Hence water lost in guttation is not pure water but a solution of minerals and will not be tasteless as the pure water of dew drops.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Loss of water from tips of leaves is called as

  1. Bleeding

  2. Guttation

  3. Respiration

  4. Transpiration
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Loss of water in vapour form through stomata is called as transpiration. Loss of water in solution form through vein endings in leaves is called as guttation. Transpiration occurs under the influence of vapour pressure gradient. Guttation is caused due to root pressure when soil is well watered and transpiration is low due to high atmospheric humidity.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Water lost in guttation is

  1. Pure water

  2. Impure water

  3. In vapour form

  4. None of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Guttation is the loss of water in solution form through hydathodes. It occurs under the influence of root pressure. When transpiration is low and plant absorbs water from well-watered soil under the influence of root pressure. The excess water oozes out as a dilute solution of minerals and other solutes from dead endings of veins. Thus, the correct answer is option B.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

The hydathodes are related with

  1. Transpiration

  2. Guttation

  3. Bleeding

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Guttation is defined as loss of water in liquid form through water stomata or hydathodes. The water is lost as a dilute solution of mineral salts. Guttation occurs under the influence of positive root pressure.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Guttation take place during night when

  1. Root pressure is positive

  2. Root pressure is negative

  3. Always take place

  4. It does not takes place at all
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Guttation is the loss of water in liquid form as a dilute solution from uninjured leaf tips. The uninjured leaf tips have hydathodes or water stomata. Under conditions of low transpiration dilute solution of minerals oozes out through them under the influence of increased root pressure. Thus, mostly guttation is observed during night time when transpiration is low, for example, due to high atmospheric humidity and sufficient water is present in soil. The most important force responsible for guttation is positive root pressure.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

Guttation takes place through

  1. Lenticels

  2. Pneumatophores

  3. Stomata

  4. Hydathodes
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Guttation is the loss of water in the form of the dilute solution which consists salts and minerals through stomata or hydathodes. Guttation occurs under the influence of root pressure when soil is well watered but humidity is high consequently transpiration is less.

Multiple choice botany transpiration guttation excretion in plants long distance transport of water

The whitish powder around hydathode is due to 

  1. Guttation

  2. Salt depositon from air

  3. Salt formation over surface

  4. Bleeding
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

Loss of water as dilute solution of minerals and salts from hydathodes is called as guttation. It is prominently seen when transpiration is low but root pressure is high. When water evaporates, the mineral salts are left behind as whitish deposits.

Therefore, the correct answer is option A.