Question

Do you think that air bubbles are helpful in measuring the rate of transpiration? If yes, briefly explain the apparatus in which air bubbles are used for this purpose.

Answer 1

Transpiration:

1. Transpiration is the method through which plants lose water vapor through their stomata.
2. Water from the stem and roots travels upwards or is 'drawn' into the leaves as a result of the plant's loss of water vapor.

Role of air bubbles in measuring transpiration rate:

1. The movement of the air bubble in the potometer corresponds to the plant's intake of water, and the distance covered by the bubble in a given period determines the rate of transpiration.

Apparatus used to measure transpiration rate by air bubbles:

1. The apparatus used for measuring transpiration is called a potometer.
2. It helps to measure the water uptake by plant's shoot.
3. During this experiment, in the capillary tube, a single air bubble is injected.
4. To bring the air bubble down to zero on the scale, the reservoir's valve is unlocked to add water.
5. A timer is started, and a specific amount of time is recorded.
6. The scale's distance traveled by the air bubble is recorded.
7. The distance covered by an air bubble inside the capillary tube over time can be used to calculate the transpiration rate.
8. The greater the water uptake rate, the faster the bubble moves and thus the anticipated rate of transpiration.

Thus, air bubbles help in measuring the transpiration rate.