Advertisements
Advertisements
प्रश्न
The given figure represents an experiment:
- Leaf A was coated with grease on both surfaces.
- Leaf B was coated with grease on the lower surface.
- Leaf C was coated with grease on the upper surface.
- Leaf D was left without any application of grease. All four leaves A, B, C and D were left in a room for about 24 hours.
- Which leaf dries first? Give reason.
- Which leaf dries last? Give reason.
उत्तर
- Leaf D: the leaf with no greasing on either surface would dry first, as it would shed the maximum amount of water from both surfaces.
- Leaf A: The leaf that was greased on both surfaces would dry out due to the fact that grease prevents water evaporation and transpiration by means of stomata, which are more prevalent on the lower surface of the leaf.
संबंधित प्रश्न
Name the following:
Any two parts of a leaf which allow transpiration.
State the functions of guard cells.
How do stomata differ from a lenticel?
Give Reasons for the following:
Guard cells are small in size and are kidney-shaped in outline.
Differentiate Between Stomata and Hydathodes.
Given below is the diagram of an experimental set up to study the process of transpiration in plants. Study the same and then answer the questions that follow:
(i) What is the colour of dry cobalt chloride paper?
(ii) Is the experimental leaf a monocot or a dicot? Give a reason to support your answer.
(iii) Why axe glass slides placed over the dry cobalt chloride papers?
(iv) After about half an hour what change, if any, would you expect to find in the cobalt chloride paper placed on the dorsal and ventral sides of the leaf? Give a reason to support your answer.
(v) Define the term ‘transpiration’.
Mark the most appropriate answer in the following:
In the mechanism of opening and closing of stomata, the important factor is
Given below is the figure of a stoma. Study the same and answer the following questions:
- Label the guidelines A and B.
- Write the exact location of the above-mentioned structures.
- Mention one important role of structure A.
- Write three important roles for structure B.
- Redraw the same figure when structures A are in flaccid condition. When does the flaccid condition occur?
