Increase in bleeding time and delay in blood coagulation is due to the deficiency of which hormone?

Options

A. Adrenaline
B. Noradrenaline
C. Parathormone
D. Thyroxine.

Answer

**Step-by-Step Solution:**

1. **Understanding the Question:**
The question asks which hormone deficiency leads to an increase in bleeding time and a delay in blood coagulation.

2. **Identifying Relevant Hormones:**
The hormones involved in blood coagulation and calcium regulation are parathormone (also known as parathyroid hormone), thyrocalcitonin, adrenaline, noradrenaline, and thyroxine.

3. **Role of Parathormone:**
Parathormone is secreted by the parathyroid glands and is primarily responsible for increasing blood calcium levels (hypercalcemia) when they are low.

4. **Effect of Calcium on Blood Coagulation:**
Calcium ions play a crucial role in the blood coagulation process. A deficiency in calcium can lead to prolonged bleeding time and delayed coagulation.

5. **Conclusion:**
When there is a deficiency of parathormone, calcium levels in the blood decrease, which in turn leads to an increase in bleeding time and a delay in blood coagulation. Therefore, the deficiency of parathormone is responsible for the symptoms described in the question.

6. **Final Answer:**
The hormone whose deficiency leads to increased bleeding time and delayed blood coagulation is **parathormone**.

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