Tony takes part in a 4x 400.m relay. His body temperature rises rapidly while he runs, in response to which, the sweat glands produce sweat to cool his body. Where does the signal to release sweat come from?

Options

A. Pituitary
B. Cerebrum
C. Cerebellum
D. Hypothalamus

Answer

To answer the question about where the signal to release sweat comes from when Tony runs in a 4x400m relay, we can break down the solution into the following steps:

### Step-by-Step Solution:

1. **Understanding the Context**: When Tony participates in the relay, his body engages in intense physical activity. This activity leads to an increase in his body temperature due to the energy produced during exercise.

2. **Body Temperature Regulation**: The human body has a normal temperature of approximately 37 degrees Celsius. When Tony's temperature rises above this level due to running, it is essential to bring it back down to maintain homeostasis.

3. **Role of the Hypothalamus**: The hypothalamus is a part of the brain that plays a crucial role in regulating body temperature. It acts as a thermostat for the body. When it detects that the body temperature is rising, it initiates responses to cool the body down.

4. **Signal to Sweat Glands**: In response to the increased body temperature, the hypothalamus sends signals to the sweat glands. This signal is part of the body's thermoregulatory response.

5. **Sweat Production**: The sweat glands then produce sweat, which is released onto the skin surface. As the sweat evaporates, it cools the body, helping to lower the temperature back to the normal range.

6. **Conclusion**: Therefore, the signal to release sweat comes from the hypothalamus, which detects the rise in body temperature and triggers the sweat glands to produce sweat for cooling.

### Final Answer:
The signal to release sweat comes from the hypothalamus, which regulates body temperature.

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