Bark refers to all tissues exterior to the

Options

A. cork cambium
B. Pericycle
C. Vascular cambium
D. Periderm

Answer

**Step-by-Step Solution:**

1. **Definition of Bark**: Bark refers to all the tissues that are located exterior to the vascular cambium in woody plants. It is important to note that bark is not found in herbaceous plants.

2. **Components of Bark**: Bark consists of two main parts: the inner bark and the outer bark. The inner bark is also known as the "phloem" and is responsible for transporting nutrients, while the outer bark is primarily composed of dead tissues.

3. **Structure of Bark**: The bark overlays the wood and is made up of several layers:
- **Periderm**: This is the protective outer layer that replaces the epidermis in woody plants. It consists of:
- **Phellogen**: The cork cambium that produces new cork cells.
- **Phellem**: The outer layer of cork cells that are dead at maturity.
- **Phelloderm**: The inner layer of living cells produced by the phellogen.

4. **Role of Vascular Cambium**: The vascular cambium is a layer of tissue that produces new xylem (wood) and phloem (inner bark). The bark is formed outside this cambium layer.

5. **Summary**: In summary, bark is the outermost layer of woody plants, consisting of all tissues outside the vascular cambium, including the inner and outer bark, which serve protective and transport functions.

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