Which one of the following pairs is not - correctly matched ?

Options

A. Pineal body : Dopamine
B. Leydig cells : Androgen
C. Intestine : Secretin
D. Neurohypophysis : Oxytocin

Answer

To determine which pair is not correctly matched, we need to analyze each of the given pairs in the question:

1. **Pineal Body and Dopamine**:
- The pineal body (or pineal gland) is primarily known for producing melatonin, which regulates sleep-wake cycles (circadian rhythms).
- Dopamine is a neurotransmitter produced mainly in the hypothalamus and is not primarily associated with the pineal body.
- Conclusion: This pair is not correctly matched.

2. **Leydig Cells and Androgen**:
- Leydig cells are located in the testes and are responsible for producing androgens, primarily testosterone.
- Conclusion: This pair is correctly matched.

3. **Intestine and Secretin**:
- Secretin is a hormone produced by the S cells in the duodenum (part of the intestine) and plays a role in regulating water homeostasis and digestive processes.
- Conclusion: This pair is correctly matched.

4. **Neurohypophysis and Oxytocin**:
- The neurohypophysis (posterior pituitary) stores and releases oxytocin, which is involved in childbirth and social bonding.
- Conclusion: This pair is correctly matched.

Based on the analysis, the pair that is not correctly matched is **Pineal Body and Dopamine**.

### Final Answer:
The pair that is not correctly matched is **Pineal Body and Dopamine**.