Biology · Homeostasis
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On a very cold day, a man waits for over an hour at the bus stop. Which of the following structures helps his body set and maintain a normal temperature?
- A
Hypothalamus
- B
Kidneys
- C
Posterior pituitary
- D
Brainstem
On a cold day, the body must maintain a stable core temperature to function properly. The hypothalamus is crucial for this task as it senses changes in body temperature and triggers responses like shivering and vasoconstriction to conserve heat. This makes the hypothalamus the correct answer. In contrast, the kidneys focus on fluid balance, the posterior pituitary on hormone release, and the brainstem on other automatic functions, none of which directly involve temperature regulation.
The hypothalamus is a central part of the brain that acts as the body's thermostat. It senses temperature changes and triggers mechanisms such as shivering or sweating to adjust and maintain a stable internal environment, making it crucial for temperature regulation.
The kidneys primarily manage fluid and electrolyte balance and excrete waste products. They do not have a direct role in regulating body temperature, which is controlled by the hypothalamus.
The posterior pituitary gland releases hormones such as oxytocin and antidiuretic hormone (ADH), which influence water balance and reproductive processes, but it does not regulate body temperature.
The brainstem manages essential automatic functions like breathing and heart rate. While it is vital for survival, it is not specifically responsible for maintaining body temperature; that role is primarily held by the hypothalamus.
Tagged under Biology · Homeostasis