PCT is responsible for

Options

A. Filtration of blood
B. Maintenance of glomerular filtration rate
C. Reabsorption of salt only
D. Selective reabsorption of glucose, amino acids, `NaCl` and `H_(2)O`

Answer

**Step-by-Step Text Solution:**

1. **Understanding the Role of PCT**: The Proximal Convoluted Tubule (PCT) is a crucial part of the nephron in the kidney. It plays a significant role in the reabsorption of various substances from the filtrate back into the blood.

2. **Filtration of Blood**: The filtration of blood primarily occurs in the glomerulus, not the PCT. Therefore, the first option stating that PCT is responsible for the filtration of blood is incorrect.

3. **Maintenance of Glomerular Filtration Rate (GFR)**: The GFR is regulated by the afferent and efferent arterioles of the glomerulus. This function is not performed by the PCT, making the second option incorrect.

4. **Reabsorption of Salt Only**: While the PCT does reabsorb salts, it is not limited to just salt. It also reabsorbs glucose, amino acids, and water. Thus, the third option is partially correct but ultimately incorrect as it does not encompass the full range of substances reabsorbed.

5. **Selective Reabsorption**: The fourth option states that the PCT is responsible for the selective reabsorption of glucose, amino acids, salts, and water. This is the most accurate description of the function of the PCT, making it the correct answer.

6. **Conclusion**: Therefore, the correct answer to the question "PCT is responsible for" is the fourth option: selective reabsorption of glucose, amino acids, salts, and water.