Post-ganglionic nerve fibres of sysmpathetic system are

Options

A. Adrenergic
B. Cholinergic
C. Voluntary
D. None of these

Answer

To answer the question regarding the nature of post-ganglionic nerve fibers of the sympathetic system, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Nervous System Division**: The nervous system is divided into two main parts: the central nervous system (CNS) and the peripheral nervous system (PNS). The PNS is further divided into the somatic nervous system and the autonomic nervous system (ANS).

2. **Identify the Autonomic Nervous System Components**: The ANS is divided into two branches: the sympathetic nervous system and the parasympathetic nervous system. Each of these systems has different roles in regulating bodily functions.

3. **Recognize the Role of Neurotransmitters**: Neurotransmitters are chemicals that transmit signals across synapses between neurons. The type of neurotransmitter released by a nerve fiber determines whether it is classified as cholinergic or adrenergic.

4. **Differentiate Between Cholinergic and Adrenergic Fibers**:
- **Cholinergic fibers**: These fibers release acetylcholine as their neurotransmitter. They are primarily found in the parasympathetic nervous system.
- **Adrenergic fibers**: These fibers release norepinephrine (noradrenaline) or epinephrine (adrenaline) as their neurotransmitter. They are primarily found in the sympathetic nervous system.

5. **Focus on Post-ganglionic Fibers**: In the sympathetic nervous system, the pre-ganglionic fibers release acetylcholine, but the post-ganglionic fibers release norepinephrine. Therefore, post-ganglionic fibers of the sympathetic system are classified as adrenergic.

6. **Conclude the Answer**: Based on the above information, the post-ganglionic nerve fibers of the sympathetic system are adrenergic.

### Final Answer:
The post-ganglionic nerve fibers of the sympathetic system are **adrenergic**.

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