Assertion (A): | Late wood has fewer xylary elements with narrow vessels. |
Reason (R): | Cambium is less active in winters. |
1. | (A) is False but (R) is True. |
2. | Both (A) and (R) are True and (R) is the correct explanation of (A). |
3. | Both (A) and (R) are True but (R) is not the correct explanation of (A). |
4. | (A) is True but (R) is False |
1. | (A), (C) and (D) only | 2. | (B), (C) and (D) only |
3. | (A), (B), (C) and (E) only | 4. | (A), (B), (D) and (E) only |
Axillary buds are derived from the activity of :
1. Lateral meristem
2. Secondary meristem
3. Apical meristem
4. Intercalary meristem
The anatomy of springwood shows some peculiar features. Identify the correct set of statements about springwood.
a. | It is also called as the early wood. |
b. | In spring season cambium produces xylem elements with narrow vessels. |
c. | It is lighter in colour. |
d. | The springwood along with autumn wood shows alternate concentric rings forming annual rings. |
e. | It has lower density. |
Choose the correct answer from the options given below:
1. (c), (d) and (e) Only
2. (a), (b), (d) and (e) Only
3. (a), (c), (d) and (e)Only
4. (a), (b) and (d) Only
In old trees the greater part of secondary xylem is dark brown and resistant to insect attack due to :
a. | secretion of secondary metabolites and their deposition in the lumen of vessels. |
b. | deposition of organic compounds like tannins and resins in the central layers of stem. |
c. | deposition of suberin and aromatic substances in the outer layer of stem. |
d. | deposition of tannins, gum, resin and aromatic substances in the peripheral layers of stem. |
e. | presence of parenchyma cells, functionally active xylem elements and essential oils. |
Choose the correct answer from the options given below
1. (b) and (d) Only
2. (a) and (b) Only
3. (c) and (d) Only
4. (d) and (e) Only