During secondary growth, amount of
(a) Heartwood increases
(b) Sapwood increases
(c) Sapwood decreases
(d) Sapwood remains almost constant
(1) Only (d)
(2) (a) and (b)
(3) (a) and (c)
(4) (a) and (d)

Options

A. Only ( d )
B. ( a ) and ( b )
C. ( a ) and ( c )
D. ( a ) and ( d )

Answer

To solve the question regarding secondary growth and the changes in heartwood and sapwood, let's analyze the options step by step.

### Step 1: Understand Secondary Growth
- Secondary growth refers to the increase in thickness of the plant stem and roots, primarily occurring in dicots and gymnosperms. This growth is facilitated by the activity of the vascular cambium and cork cambium.

### Step 2: Analyze Heartwood and Sapwood
- **Heartwood**: This is the inner, older xylem that no longer conducts water and is typically denser and darker. During secondary growth, heartwood increases as older sapwood becomes heartwood.
- **Sapwood**: This is the outer, younger xylem that is still active in water conduction. As trees age, some of the sapwood is converted into heartwood.

### Step 3: Evaluate the Options
- (a) Heartwood increases: This statement is true as heartwood forms from the conversion of sapwood over time.
- (b) Sapwood increases: This statement is false; sapwood does not increase as it is gradually converted into heartwood.
- (c) Sapwood decreases: This statement is true because as sapwood is converted into heartwood, the amount of sapwood decreases.
- (d) Sapwood remains almost constant: This statement is false; sapwood does not remain constant as it decreases over time.

### Step 4: Determine the Correct Answer
From the analysis:
- The correct statements are (a) and (c). Therefore, the correct answer is option (3) (a) and (c).

### Final Answer
The correct option is (3) (a) and (c).

---