What is true about cork cambium?

Options

A. It is extrastelar cambium in dicot stem
B. In dicot roots it arises from the cells of cortex region
C. It is also known as phellogen
D. Both ( a ) & ( c )

Answer

To determine what is true about cork cambium, we need to analyze the provided options based on our understanding of cork cambium's characteristics and functions.

### Step-by-Step Solution:

1. **Understanding Cork Cambium**:
- Cork cambium, also known as phellogen, is a type of lateral meristematic tissue responsible for the secondary growth in plants, particularly in the stems and roots of dicots.

2. **Evaluating Option 1**:
- **Option 1** states that cork cambium is an extracellular cambium in dicot stem.
- This is true because cork cambium is indeed involved in the secondary growth of dicot stems, and it is located in the cortex, making it an extracellular cambium.

3. **Evaluating Option 2**:
- **Option 2** claims that in dicot roots, cork cambium arises from the cells of the cortex region.
- This is false. In dicot roots, cork cambium does not arise from the cortex; it typically arises from the pericycle.

4. **Evaluating Option 3**:
- **Option 3** states that cork cambium is also known as sphalogen.
- This is true. Cork cambium is indeed referred to as phellogen or sphalogen, which is the term used for the tissue that produces cork.

5. **Evaluating Option 4**:
- **Option 4** states that both A and C are correct.
- Since we have established that both Option 1 and Option 3 are true, this option is also correct.

### Conclusion:
Based on the evaluations:
- Option 1 is true.
- Option 2 is false.
- Option 3 is true.
- Therefore, Option 4 (both A and C) is the correct answer.

### Final Answer:
**The correct answer is Option 4: Both A and C are true about cork cambium.**

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