Cannabinoid receptors are principally present in the _______and are known for affecting the ________system.

Options

A. brain, cardiovascular
B. brain, nervous
C. heart, cardiovascular
D. heart , nervous

Answer

To solve the question regarding cannabinoid receptors, we can break it down into two parts: where these receptors are principally found and what system they affect.

### Step-by-Step Solution:

1. **Identify the Location of Cannabinoid Receptors**:
- Cannabinoid receptors are primarily located in the **brain**. This is because these receptors are part of the endocannabinoid system, which plays a crucial role in various physiological processes and is predominantly found in the central nervous system.

2. **Determine the System Affected by Cannabinoid Receptors**:
- Cannabinoid receptors are known to affect the **nervous system**. While they can also have effects on other systems, such as the cardiovascular system, their primary and most significant effects are observed in the nervous system, influencing mood, memory, pain sensation, and other neurological functions.

### Final Answer:
Cannabinoid receptors are principally present in the **brain** and are known for affecting the **nervous system**.

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