Advertisements
Advertisements
प्रश्न
Droplets of water may sometimes be seen along the margins of the leaves of a banana plant, growing in wet soil, in the mornings. Are these dew drops? Comment upon your answer.
Advertisements
उत्तर
No, they are not dew drops.
This is water given out by the plant body through guttation. Since the banana plant is growing in humid environment, transpiration is hampered. But the roots continue to absorb water from the soil. This builds up a huge hydrostatic pressure within the plant and forces out the excess water from the hydathodes, which are pores present at the tips of veins in the leaf. This is observed especially during the mornings.
संबंधित प्रश्न
Name the following:
An instrument used to find the rate of transpiration.
What is a photometer?
Given below is the diagram of an apparatus used to study a particular phenomenon in plants:

- Name the apparatus.
- What is it used for?
- What is the role played by the air-bubble in this experiment?
- What is the use of the reservoir?
- What happens to the movement of the air-bubble if the apparatus is kept:
- in the dark
- in sunlight
- in front of a fan?
Give a reason in each case.
Given below is the diagram of an apparatus used to study a particular phenomenon in plants:

What is the use of the reservoir?
Given below is the diagram of an apparatus used to study a particular phenomenon in plants:

What happens to the movement of the air-bubble if the apparatus is kept:
(i) In the dark
(ii) In sunlight
(iii) In front of a fan
Give a reason in each case.
Write any two limitations of using a Ganong's potometer to demonstrate the uptake of water.
Match the terms given in column A with column B:
| Column A | Column B | ||
| (a) | Hydathodes | (i) | Photosynthesis |
| (b) | Stomata | (ii) | Respiration |
| (c) | Cuticle | (iii) | Regulates opening and closing of stomata |
| (d) | Lenticels | (iv) | Reduces loss of water |
| (e) | Guard cells | (v) | Guttation |
Name four kinds of potometers on the basis of the names of the scientists who discovered them.
Define the following term:
Potometer
