The chief function of intercalated discs is  

Options

A. slow conduction of action potentials
B. conduction of resting potentials
C. slow conduction of resting potentials
D. rapid conduction of action potentials

Answer

To answer the question regarding the chief function of intercalated discs, we can break it down into the following steps:

### Step-by-Step Solution:

1. **Identify the Structure**: Intercalated discs are specialized structures found in cardiac muscle tissue. They are critical for the function of the heart.

2. **Understand Their Function**: The primary role of intercalated discs is to facilitate communication between cardiac muscle cells. They contain gap junctions that allow for the rapid transmission of electrical impulses.

3. **Evaluate the Options**:
- **Option 1**: Slow conduction of action potential - This is incorrect because intercalated discs actually promote rapid conduction.
- **Option 2**: Conduction of resting potential - This is also incorrect as intercalated discs are not involved in the conduction of resting potential.
- **Option 3**: Slow conduction of resting potential - This is incorrect for the same reasons as above.
- **Option 4**: Rapid conduction of action potential - This is correct because intercalated discs allow for the quick spread of action potentials across cardiac muscle cells, enabling the heart to contract as a unit.

4. **Conclusion**: The chief function of intercalated discs is to enable rapid conduction of action potentials, ensuring that the heart beats efficiently and effectively.

### Final Answer:
The chief function of intercalated discs is **rapid conduction of action potential** (Option 4).

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