In a T.S of sunflower root, which sequence is correct from inner to outer side.

Options

A. Endodermis`to` pericycle `to` cortex `to` epiblema
B. Pericycle `to` endodermis `to` cortex `to` epiblema
C. Epiblema `to` cortex `to` endodermis `to` pericycle
D. Cortex `to` Epiblema `to` pericycle `to` endodermis

Answer

To determine the correct sequence of layers from the inner to the outer side in a transverse section (T.S.) of a sunflower root, we can follow these steps:

### Step-by-Step Solution:

1. **Identify the Innermost Layer**:
- The innermost layer of the sunflower root is the **pericycle**. This layer is located just inside the endodermis and plays a role in the formation of lateral roots.

2. **Next Layer - Endodermis**:
- Outside the pericycle is the **endodermis**. This layer consists of barrel-shaped cells and contains suberin, which makes it impermeable to water, thus regulating water flow into the vascular system.

3. **Third Layer - Cortex**:
- The next layer moving outward is the **cortex**. The cortex is made up of parenchyma cells, which are involved in storage and transport of nutrients.

4. **Outermost Layer - Epiblema (Epidermis)**:
- Finally, the outermost layer is the **epiblema**, also known as the epidermis. This layer serves as a protective barrier for the root and may have root hairs to increase surface area for water absorption.

### Correct Sequence from Inner to Outer:
- **Pericycle** → **Endodermis** → **Cortex** → **Epiblema (Epidermis)**

### Final Answer:
The correct sequence from inner to outer side in a T.S. of sunflower root is:
**Pericycle → Endodermis → Cortex → Epiblema (Epidermis)**

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