Purkinje's fibres are special types of

Options

A. Muscle fibers located in heart
B. Nerve fibers located in cerebrum
C. Connective tissue fibers joining one bone to another bone
D. Sensory fibers extending from retina into optic nerve

Answer

**Step-by-Step Solution:**

1. **Understanding Purkinje Fibres**: Purkinje fibres are specialized structures found in the heart. They are part of the heart's conduction system, which is responsible for coordinating the heartbeat.

2. **Identifying the Origin**: The Purkinje fibres were discovered by Jan Evangelista Purkinje, who published his findings related to the heart's conduction system.

3. **Location of Purkinje Fibres**: These fibres are located in the subendocardium, which is the innermost layer of the heart wall.

4. **Characteristics of Purkinje Fibres**:
- They are larger than typical cardiac muscle cells (cardiomyocytes).
- They contain fewer myofibrils, which are the contractile units of muscle cells.
- They have a high concentration of glycogen and mitochondria, which provide energy for their function.

5. **Function of Purkinje Fibres**: The primary role of Purkinje fibres is to conduct electrical impulses rapidly and efficiently to the ventricular muscles, ensuring synchronized contraction of the heart.

6. **Evaluating the Options**:
- Option 1: Muscle fibre located in the heart (correct).
- Option 2: Nerve fibres located in the cerebrum (incorrect).
- Option 3: Connective tissue fibres joining one bone to another bone (incorrect).
- Option 4: Sensory fibres extending from the retina into optic nerves (incorrect).

7. **Conclusion**: Based on the characteristics and functions of Purkinje fibres, the correct answer is that they are special types of muscle fibres located in the heart.

**Final Answer**: Purkinje's fibres are special types of muscle fibres located in the heart.

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