Explanation:

Neurotransmitters are chemicals found in the body that help transmit signals between neurons. They play a crucial role in the functioning of the nervous system.

Out of the options given, cortisone is not a neurotransmitter. Here's why:

What are neurotransmitters?

Neurotransmitters are chemical messengers that transmit electrical signals between neurons. They are released from the axon of one neuron and travel across the synapse to bind to receptors on the dendrites of another neuron. This process helps to facilitate communication between neurons and is essential for the proper functioning of the nervous system.

The options:

1. GABA: Gamma-aminobutyric acid (GABA) is a neurotransmitter that helps to reduce neuronal excitability. It is the main inhibitory neurotransmitter in the brain and is involved in regulating anxiety, sleep, and muscle tone.

2. Aspartic acid: Aspartic acid is not a neurotransmitter. It is an amino acid that is involved in protein synthesis.

3. Cortisone: Cortisone is not a neurotransmitter. It is a hormone that is produced by the adrenal gland and is involved in regulating the body's response to stress.

4. Serotonin: Serotonin is a neurotransmitter that is involved in regulating mood, appetite, and sleep. It is also involved in the regulation of pain and is the target of many antidepressant medications.

Conclusion:

In conclusion, cortisone is not a neurotransmitter. While neurotransmitters play a crucial role in the functioning of the nervous system, hormones like cortisone are involved in regulating other bodily functions.

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