Purkinje fibres are components of 

Options

A. Periosteum of bone
B. Conduction system of heart
C. matrix of calcified cartilage
D. Intercalated discs of cardiac muscle

Answer

**Step-by-Step Solution:**

1. **Understanding Purkinje Fibres**:
- Purkinje fibres are specialized fibrous tissues that play a crucial role in the conduction system of the heart. They are responsible for transmitting electrical impulses that coordinate the heart's contractions.

2. **Analyzing the Options**:
- **Option A: Periosteum of Bone**: The periosteum is a dense layer of vascular connective tissue enveloping the bones except at the surfaces of the joints. It does not contain Purkinje fibres.
- **Option B: Conduction System of Heart**: This is the correct option. Purkinje fibres are part of the heart's conduction system, which includes the sinoatrial (SA) node, atrioventricular (AV) node, and the bundle of His, among others.
- **Option C: Matrix of Calcified Cartilage**: Purkinje fibres are not found in the matrix of calcified cartilage. This option is incorrect.
- **Option D: Intercalated Discs of Cardiac Muscles**: Intercalated discs are specialized connections between cardiac muscle cells, but they are not the same as Purkinje fibres. Therefore, this option is also incorrect.

3. **Conclusion**:
- After analyzing all the options, the only correct answer is **Option B: Conduction System of Heart**.

**Final Answer**: Purkinje fibres are components of the **conduction system of the heart**.

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