What is true about glomerular filtration ?

Options

A. Selective process and active process
B. Non selective process and active process
C. Non selective process and passive process
D. Selective process and passive process

Answer

**Step-by-Step Solution:**

1. **Understanding Glomerular Filtration**:
- Glomerular filtration refers to the process by which blood is filtered in the kidneys, specifically in the glomeruli, to form urine. It measures how much blood passes through the kidneys per minute.

2. **Normal Rate of Glomerular Filtration**:
- The normal glomerular filtration rate (GFR) is typically around 60 ml/min or higher. This indicates a healthy kidney function.

3. **Characteristics of Glomerular Filtration**:
- Glomerular filtration is a **non-selective process**. This means that it does not selectively filter out certain substances; instead, it allows all small molecules and water to pass through while retaining larger molecules like proteins and blood cells.

4. **Active vs. Passive Process**:
- Glomerular filtration is a **passive process**. It does not require energy (ATP) to occur. The filtration happens due to pressure differences in the glomeruli, allowing substances to move from the blood into the renal tubules without the need for energy expenditure.

5. **Conclusion**:
- Based on the characteristics of glomerular filtration, we can conclude that it is a non-selective and passive process. Therefore, the statement that correctly describes glomerular filtration is that it is a non-selective and passive process.

**Final Answer**: Glomerular filtration is a non-selective and passive process.

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