NCERT textbook says that plant growth is unique. What is the character of plant growth being referred to?
1. Plants have a closed growth
2. Capacity of unlimited growth throughout life
3. Complete absence of growth after a certain age
4. Growth without development
Given below are two statements: one is labelled as Assertion (A) and the other is labelled as Reason (R):
Assertion (A): | Plants retain the capacity for unlimited growth throughout their life. |
Reason (R): | Plants have meristems at certain locations in their body. |
In the light of the above statements choose the correct answer from the options given below:
1. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
2. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
3. | (A) is True but (R) is False. |
4. | Both (A) and (R) are False. |
Assertion (A): | Unlike animals, plants retain the capacity for unlimited growth throughout their life. |
Reason (R): | Unlike animals, there is presence of meristems at certain locations in their body. |
1. | Both (A) and (R) are True and (R) correctly explains (A). |
2. | (A) is True; (R) is False |
3. | (A) is False; (R) is False |
4. | Both (A) and (R) are True but (R) does not correctly explain (A). |
I: | Root apical meristem |
II: | Shoot apical meristem |
III: | Vascular cambium |
IV: | Cork-cambium |
Statement I: | The root apical meristem and the shoot apical meristem are responsible for the primary growth of the plants and cause the increase in the girth of the organs in which they are active. |
Statement II: | In dicotyledonous plants and gymnosperms, the lateral meristems, vascular cambium and cork-cambium principally contribute to the elongation of the plants along their axis. |
1. | Growth is primarily expressed as increase in number of cells at the root apical meristem in maize. |
2. | Growth is primarily represented as increase in size of cells in watermelons. |
3. | Growth of a pollen tube is measured in terms of its girth. |
4. | An increase in surface area denotes the growth in a dorsiventral leaf. |
Assertion (A): | Growth, at the cellular level, is measured by a variety of parameters, some of which are: increase in fresh weight, dry weight, length, area, volume and cell number. |
Reason (R): | Growth, at a cellular level, is principally a consequence of an increase in the amount of protoplasm, and increase in protoplasm is difficult to measure directly. |
1. | Both (A) and (R) are True and (R) correctly explains (A). |
2. | Both (A) and (R) are True but (R) does not correctly explain (A). |
3. | (A) is True; (R) is False. |
4. | (A) is False; (R) is True. |
Match Column I [phase of growth] and Column II [cell characteristics] and choose the correct answer from the codes given:
Column I | Column II | ||
A. | Meristematic | a. | Increased vacuolation, new cell wall deposition |
B. | Elongation | b. | Thin cellulosic wall with abundant plasmodesmatal connections |
C. | Maturation | c. | Maximal wall thickening |
Codes
A | B | C | |
1. | a | b | c |
2. | b | c | a |
3. | b | a | c |
4. | c | b | a |
1. | They are constantly dividing cells. |
2. | They are rich in protoplasm, possess large conspicuous nuclei. |
3. | Their cell walls are primary in nature. |
4. | Plasmodesmatal connections between the cells are absent. |