Regulation of body temperature ：練習問題

Which of the following correctly describes the role of the hypothalamus in the homeostatic regulation of body temperature?

During exposure to a cold environment, which of the following describes how shivering generates heat?

Which of the following correctly describes the negative feedback loop when the core body temperature falls below \(37^\circ\text{C}\)?

Which of the following is the most significant physiological mechanism for heat loss in humans when the ambient temperature is higher than body temperature?

During a fever, the body's thermoregulatory set point in the hypothalamus is temporarily raised. What is the immediate physiological consequence of this change?

When the body is exposed to a cold environment, the hair erector muscles contract. State the name of this response and identify the structure that acts as the effector.

Describe the nervous coordination involved when temperature receptors in the skin detect a sharp drop in environmental temperature, leading to a protective response.

Explain how vasoconstriction of skin arterioles and the diversion of blood to internal organs act together as a heat conservation mechanism, and predict the physiological effect on the skin surface temperature during this process.

When a person is performing strenuous physical exercise, their core body temperature tends to rise significantly. To maintain homeostasis, the body initiates several mechanisms to increase heat loss.

Describe two distinct physiological mechanisms, primarily involving the skin and circulation, that work in a coordinated manner to facilitate heat dissipation during exercise, and explain the mechanism of action for each. (3 marks)

The human body uses both immediate and sustained methods to increase heat generation when exposed to cold.

(a) Explain the physiological mechanism of shivering and state the system (nervous or endocrine) primarily responsible for initiating it. (2 marks)
(b) Describe the role of the hormone thyroxine in long-term heat production and explain why this response is considered more sustained than shivering. (2 marks)