Homeostasis & Temperature: Keeping Cool and Staying Warm

 

What is Homeostasis?

• Homeostasis is your body's way of keeping its internal environment stable.
• For temperature, it ensures your body stays at around $37 \degree C$-the ideal temperature for enzymes to work properly.

Analogy: Think of your body as a thermostat. When it gets too hot or cold, it adjusts automatically to maintain balance.

 

How Does Your Body Control Temperature?

• The hypothalamus in your brain acts like a temperature sensor.
• It detects changes in body temperature and triggers responses to bring it back to normal.
• This is an example of negative feedback.

 

Homeostasis: The skin and regulating Temperature

 

 

Responses to Temperature Changes

When Too Hot	When Too Cold
Sweating: Sweat glands release sweat, which evaporates to cool the body.	Shivering: Muscles contract rapidly to generate heat.
Vasodilation: Blood vessels near the skin widen, increasing blood flow and heat loss.	Vasoconstriction: Blood vessels near the skin narrow, reducing heat loss.
Hairs lie flat: Reduces insulation so heat can escape.	Hairs stand up: Traps a layer of warm air for insulation.
Reduced metabolism: The body slows down energy production to prevent overheating.	Increased metabolism: The body speeds up energy production to generate heat.

 

Key Processes Explained

1. Sweating:

   • Sweat absorbs heat from your skin as it evaporates, cooling you down.
   • Tip: Sweating works best in dry air, not humid conditions.

2. Vasodilation:

   • Blood vessels near the skin surface widen.
   • This allows more heat to escape through radiation.
   • Think of it like opening windows to cool down a hot room.

3. Shivering:

   • Muscles contract rapidly, generating heat through respiration.
   • This is like your body "exercising" to stay warm.

4. Vasoconstriction:

   • Blood vessels near the skin surface narrow.
   • This reduces blood flow to the skin, conserving heat.
   • Imagine closing windows to keep heat inside a room.

 

Negative Feedback in Temperature Regulation

Negative feedback helps maintain a set point for temperature (around $37 \degree C$ ).

• If the body gets too hot, processes like sweating and vasodilation cool it down.
• If the body gets too cold, processes like shivering and vasoconstriction warm it up.