Parasympathetic ganglia are located in

Options

A. Next to or within the organs innervated
B. A chain parallel to the spinal cord
C. The root of spinal nerves
D. The brain

Answer

To answer the question "Parasympathetic ganglia are located in," we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Nervous System Structure**:
- The nervous system is divided into two main parts: the Central Nervous System (CNS) and the Peripheral Nervous System (PNS).
- The CNS comprises the brain and spinal cord, while the PNS includes all the nerves outside the CNS.

2. **Identify the Components of the Autonomic Nervous System**:
- The PNS is further divided into the Somatic Nervous System and the Autonomic Nervous System.
- The Autonomic Nervous System is further divided into the Sympathetic and Parasympathetic divisions.

3. **Locate the Parasympathetic Ganglia**:
- Parasympathetic ganglia are clusters of nerve cell bodies that are part of the parasympathetic division.
- These ganglia are typically located close to or within the organs they innervate, meaning they are situated near the target organs.

4. **Evaluate the Given Options**:
- **Next to or within the organs innervated**: This option aligns with the known anatomical location of parasympathetic ganglia.
- **A chain parallel to the spinal cord**: This describes the sympathetic ganglia, not parasympathetic.
- **The root of spinal nerves**: This is incorrect as it pertains to the spinal cord and not the location of parasympathetic ganglia.
- **The brain**: While some parasympathetic fibers originate in the brain, the ganglia themselves are not located in the brain.

5. **Select the Correct Answer**:
- Based on the analysis, the correct answer is **next to or within the organs innervated**.

### Final Answer:
Parasympathetic ganglia are located **next to or within the organs innervated**.

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