All the following statements about cannabinoids are true , except

Options

A. Cannabinoids are known for their effects on cardiovascular system
B. Cannabinoids are obtained from leaves and flowers of hemp plant.
C. Cannabinoids interact with cannabinoid receptors present principally in brain .
D. Coke or Crack is a very commonly abused cannabinoid .

Answer

To solve the question regarding cannabinoids, we need to analyze each of the given statements to determine which one is false.

### Step-by-Step Solution:

1. **Understanding Cannabinoids**: Cannabinoids are chemical compounds that interact with cannabinoid receptors in the body. They are primarily found in the cannabis plant.

2. **Evaluating the First Statement**:
- The first statement claims that cannabinoids are known for their effects on the cardiovascular system.
- This statement is true. Cannabinoids can affect the cardiovascular system by increasing heart rate and causing blood vessels to dilate.

3. **Evaluating the Second Statement**:
- The second statement states that cannabinoids are obtained from the leaves and flowers of the hemp plant.
- This statement is also true. Cannabinoids are indeed extracted from the leaves and flowers of the cannabis (hemp) plant.

4. **Evaluating the Third Statement**:
- The third statement mentions that cannabinoids interact with cannabinoid receptors present principally in the brain.
- This statement is true as well. Cannabinoids primarily interact with receptors in the brain, leading to various physiological effects.

5. **Evaluating the Fourth Statement**:
- The fourth statement claims that "Quark" is a commonly abused cannabinoid.
- This statement is false. "Quark" is not recognized as a cannabinoid and is not commonly abused. This makes it the incorrect statement among the options provided.

### Conclusion:
The statement that is not true about cannabinoids is the one referring to "Quark" as a commonly abused cannabinoid.

### Final Answer:
The correct answer is: "Quark is a commonly abused cannabinoid."

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