Serum differs from blood in

Options

A. lacking globulins
B. lacking albumins
C. lacking clotting factors
D. lacking antibodies

Answer

**Step-by-Step Solution:**

1. **Understanding Blood Composition**: Blood is a vital fluid in the circulatory system that consists of various components, including red blood cells (RBCs), white blood cells (WBCs), platelets (clotting factors), and plasma.

2. **Identifying Blood Components**:
- **RBCs**: Responsible for transporting oxygen and carbon dioxide.
- **WBCs**: Act as defense cells against foreign antigens.
- **Platelets**: Also known as thrombocytes, they play a crucial role in blood clotting.

3. **Separation of Blood Components**: When blood is collected in a vial and allowed to settle, it undergoes a process where it separates into different layers. The top layer consists of the clot (formed by platelets and clotting factors), while the bottom layer is the liquid component.

4. **Defining Serum**: The liquid that remains after the clotting factors have been removed from the blood is called serum. It is essentially the fluid part of blood without the clotting factors.

5. **Key Differences Between Serum and Blood**:
- Serum lacks clotting factors, which are present in whole blood.
- Serum does not contain cells (RBCs and WBCs) or platelets, which are found in blood.

6. **Conclusion**: Therefore, serum differs from blood primarily in that it lacks clotting factors and cellular components, making it a clear fluid that remains after the blood has clotted.

---