Each nerve fibre in a nerve is surrounded by a
layer of connective tissue , known as

Options

A. epineurium
B. perineurium
C. endoneurium
D. exoneurium

Answer

To answer the question "Each nerve fibre in a nerve is surrounded by a layer of connective tissue, known as," we need to identify the correct term from the options provided: epineurium, perineurium, endoneurium, or exoneurium.

### Step-by-Step Solution:

1. **Understanding the Structure of Nerves**: Nerves are made up of bundles of nerve fibers. Each nerve fiber is an individual unit within the nerve.

2. **Identifying the Layers of Connective Tissue**:
- **Epineurium**: This is the outermost layer of connective tissue that surrounds the entire nerve. It does not surround individual nerve fibers but rather the whole nerve.
- **Perineurium**: This layer surrounds bundles (or fascicles) of nerve fibers. It provides protection and support to groups of nerve fibers but does not cover individual fibers.
- **Endoneurium**: This is the innermost layer of connective tissue that surrounds each individual nerve fiber. It provides support and insulation to each nerve fiber.
- **Exoneurium**: This term is not commonly used in the context of nerve structure and does not represent a recognized layer of connective tissue surrounding nerve fibers.

3. **Determining the Correct Answer**: Since the question specifically asks about the layer that surrounds each individual nerve fiber, the correct answer is **endoneurium**.

### Final Answer:
Each nerve fibre in a nerve is surrounded by a layer of connective tissue known as **endoneurium**.

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