Question

Which parameter may be used to determine acclimatization to cold climate?

• A. Increased metabolic rate
• B. Reduced respiratory rate
• C. Reduced cardiac output
• D. Increased Iron deficiency

Hint:

Think of the body as a furnace. To stay warm in the cold, you need to turn up the heat. In physiological terms, "turning up the heat" means increasing your metabolic rate.

Answer 1

The Correct Option is A

Step 1: Understanding the Concept:
Acclimatization refers to the physiological adjustments an organism makes in response to a change in an environmental factor, such as temperature. In a cold climate, the primary physiological challenge is to maintain core body temperature (thermoregulation) by increasing heat production and reducing heat loss.
Step 2: Detailed Explanation:
- Increased metabolic rate: The body produces heat through metabolic processes. To counteract cold stress, the basal metabolic rate (BMR) can increase, generating more internal heat. This is a primary mechanism for cold acclimatization. Shivering is a short-term response, while a sustained increase in BMR is a longer-term acclimatization.
- Reduced respiratory rate: This is not a typical response to cold. Breathing rates are more closely tied to oxygen demand and carbon dioxide levels.
- Reduced cardiac output: In the cold, the body may need to increase circulation to extremities to prevent frostbite, or it might constrict peripheral blood vessels to conserve core heat. A general reduction in cardiac output is not a primary adaptive mechanism for heat production.
- Increased Iron deficiency: Iron deficiency (anemia) is a pathological condition, not a beneficial adaptation. It would likely impair the body's ability to cope with cold stress due to reduced oxygen-carrying capacity.
Step 3: Final Answer:
The most direct and significant physiological parameter that indicates acclimatization to cold by increasing heat production is an increased metabolic rate.