Read the statements given below and select the correct option

Options

A. Atrial natriuretic factor (ANF) is responsible for increasing the blood pressure .
B. Gastrin stimulates the secretion of HCl and trypsinogen.
C. Erythropoietin is produced by Juxta - Glomerular cells of the kidney .
D. CCK acts only on the gall bladder.

Answer

To solve the question regarding the statements about various biological factors and hormones, we will analyze each statement one by one to determine their validity.

### Step-by-Step Solution:

1. **Statement 1: Atrial Natriuretic Factor (ANF) is responsible for increasing blood pressure (BP).**
- **Analysis:** This statement is false. ANF is secreted in response to increased blood pressure or blood volume. Its primary function is to decrease blood pressure by promoting the excretion of sodium and water by the kidneys, thus reducing blood volume.
- **Conclusion:** This statement is incorrect.

2. **Statement 2: Gastrin stimulates the secretion of HCl and trypsinogen.**
- **Analysis:** This statement is also false. Gastrin is a hormone that stimulates the secretion of hydrochloric acid (HCl) from the gastric mucosa and pepsinogen from the stomach. However, trypsinogen is secreted by the pancreas, not directly stimulated by gastrin.
- **Conclusion:** This statement is incorrect.

3. **Statement 3: Erythropoietin is produced by the juxtaglomerular cells of the kidney.**
- **Analysis:** This statement is true. Erythropoietin is indeed produced by the kidneys, specifically by the interstitial fibroblasts in the renal cortex, and it plays a crucial role in stimulating the production of red blood cells in response to low oxygen levels.
- **Conclusion:** This statement is correct.

4. **Statement 4: CCK (Cholecystokinin) acts only on the gallbladder.**
- **Analysis:** This statement is false. CCK acts on both the gallbladder (stimulating it to release bile) and the pancreas (stimulating it to release digestive enzymes and bicarbonate).
- **Conclusion:** This statement is incorrect.

### Final Conclusion:
The only correct statement among the given options is **Statement 3**: Erythropoietin is produced by the juxtaglomerular cells of the kidney. Therefore, the correct answer is option number 3.

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