Which one of the following does not match in biological category of chemical substance?

Options

A. Gastrin
B. Renin
C. Oxytocin
D. Creatinine

Answer

To solve the question of which one of the following does not match in the biological category of chemical substances, we will analyze each option provided: Gastrin, Renin, Oxytocin, and Creatinine.

### Step-by-Step Solution:

1. **Identify Gastrin**:
- Gastrin is a hormone produced in the gastrointestinal tract. Its primary function is to stimulate the secretion of gastric acid (hydrochloric acid) and pepsinogen, which aids in digestion.

2. **Identify Renin**:
- Renin is also a hormone, secreted by the juxtaglomerular cells of the kidneys. It plays a crucial role in the regulation of blood pressure by converting angiotensinogen into angiotensin I, which is part of the renin-angiotensin system.

3. **Identify Oxytocin**:
- Oxytocin is a hormone produced by the hypothalamus and released by the posterior pituitary gland. It is known for its role in childbirth, as it stimulates uterine contractions, and it also has roles in social bonding and lactation.

4. **Identify Creatinine**:
- Creatinine is a waste product formed from the normal breakdown of muscle tissue. It is not a hormone; instead, it is filtered out of the blood by the kidneys and excreted in urine.

5. **Conclusion**:
- Among the four options, Gastrin, Renin, and Oxytocin are all hormones, while Creatinine is a waste product. Therefore, the odd one out is **Creatinine**.

### Final Answer:
**Creatinine** does not match in the biological category of chemical substances as it is not a hormone.

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