Parkinson's diseases (characterised by tremorse and progressive rigidity of limbs) is caused by degeneration of brain neutrons that are involved in movement control and make use of neurotransmitter

Options

A. Norepinephrine
B. Acetylcholine
C. GABA
D. Dopamine

Answer

### Step-by-Step Solution:

1. **Understanding Parkinson's Disease**:
- Parkinson's disease is a neurodegenerative disorder characterized by tremors and progressive rigidity of limbs. It primarily affects movement control.

2. **Identifying the Cause**:
- The disease is caused by the degeneration of specific neurons in the brain. The neurons that are primarily affected are located in a region called the **substantia nigra**.

3. **Role of Substantia Nigra**:
- The substantia nigra is a structure in the midbrain that is part of the basal ganglia. It plays a crucial role in the regulation of movement and reward.

4. **Neurotransmitter Involvement**:
- The neurons in the substantia nigra produce a neurotransmitter that is essential for movement control. This neurotransmitter is **dopamine**.

5. **Evaluating Other Neurotransmitters**:
- To confirm that dopamine is the correct answer, we can evaluate the other neurotransmitters mentioned:
- **Norepinephrine**: Involved in alertness and the body's fight or flight response, not directly related to movement control.
- **Acetylcholine**: Functions in the autonomic nervous system, aiding in muscle contraction and heart rate regulation, but not specifically in movement control related to Parkinson's.
- **GABA**: Acts as an inhibitory neurotransmitter, reducing neuronal excitability and controlling anxiety, but not directly involved in movement control.

6. **Conclusion**:
- Given that dopamine is the neurotransmitter produced by the substantia nigra and is directly involved in movement control, it is the correct answer to the question regarding the neurotransmitter involved in Parkinson's disease.

### Final Answer:
- The neurotransmitter involved in Parkinson's disease is **dopamine**.

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