Question

Which of the following cases decreases blood pressure?

• A. Blood loss in accident.
• B. Inelasticity of blood vessels.
• C. Increase in peripheral resistance.
• D. Increase in secretion of ADH.

Hint:

Blood loss reduces blood volume and thus lowers blood pressure. Immediate treatment is necessary to restore blood volume and prevent shock.

Answer 1

The Correct Option is A

Step 1: Blood loss in an accident leads to a decrease in blood volume, which in turn reduces blood pressure. The body compensates by increasing heart rate and constricting blood vessels, but these mechanisms may not be sufficient to restore normal blood pressure.

Step 2:
- (B) Inelasticity of blood vessels: Leads to increased peripheral resistance, which would increase blood pressure, not decrease it.
- (C) Increase in peripheral resistance: This increases blood pressure by making it harder for the blood to flow through the vessels.
- (D) Increase in secretion of ADH: While ADH causes the kidneys to retain water, increasing blood volume and blood pressure, it does not immediately decrease blood pressure.

Conclusion: Blood loss reduces blood volume, causing a drop in blood pressure, making \( (A) \) the correct answer.