Which will not coagulate

Options

A. Blood serum
B. Blood plasma
C. Lymph
D. Whole blood.

Answer

To solve the question "Which will not coagulate?" we need to analyze the options provided: blood serum, blood plasma, lymph, and whole blood.

### Step-by-Step Solution:

1. **Understanding Coagulation**: Coagulation is the process where blood changes from a liquid to a gel, forming a blood clot. This process requires the presence of clotting factors.

2. **Analyzing Blood Serum**:
- Blood serum is the liquid that remains after blood has clotted.
- It is obtained by removing the clotting factors from blood plasma.
- Since blood serum lacks clotting factors, it will **not coagulate**.

3. **Analyzing Blood Plasma**:
- Blood plasma is the liquid component of blood that contains water, electrolytes, proteins (including clotting factors), hormones, and nutrients.
- Since blood plasma contains clotting factors, it will **coagulate**.

4. **Analyzing Lymph**:
- Lymph is a fluid that is part of the lymphatic system and is derived from interstitial fluid.
- Although lymph does not contain blood platelets, it does contain some clotting factors.
- Therefore, lymph can **coagulate**, albeit at a slower rate than blood plasma.

5. **Analyzing Whole Blood**:
- Whole blood consists of blood plasma and all the formed elements (RBCs, WBCs, and platelets).
- Since it contains both plasma and clotting factors, whole blood will **coagulate**.

6. **Conclusion**:
- Among the options provided, **blood serum** is the only component that will not coagulate because it lacks clotting factors.

### Final Answer:
**Blood serum will not coagulate.**

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