Urea is transported through

Options

A. RBCs
B. WBCs
C. Plasma
D. All of the above

Answer

**Step-by-Step Solution:**

1. **Understanding Urea**: Urea is a toxic waste product formed in the body, primarily in the liver, as a result of protein metabolism. It needs to be excreted from the body to maintain health.

2. **Formation of Urea**: Urea is synthesized in the liver through a process called the urea cycle, where ammonia (a toxic byproduct of protein breakdown) is converted into urea, which is less toxic.

3. **Transportation of Urea**: Once urea is formed in the liver, it must be transported to the kidneys for excretion. The transportation of urea occurs through the bloodstream.

4. **Role of Plasma**: The component of blood responsible for transporting urea is plasma. Plasma is the liquid part of blood that carries various substances, including nutrients, hormones, and waste products like urea.

5. **Excretion of Urea**: After reaching the kidneys, urea is filtered out of the blood and excreted from the body through urine.

6. **Conclusion**: Therefore, the correct answer to the question "Urea is transported through" is plasma.

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