Homeostasis

How do you maintain a steady body temperature when you're exposed to ice packs, or hot water bottles? Healthy Body temperature is 37 degrees Celsius, or 98.6 degrees Fahrenheit. I need to keep a steady temperature near 98.6 degrees Fahrenheit, or else crucial molecules in my body will change shape and stop working, and I'll die. Homeostasis is the scientific term for my body's ability to maintain its proper equilibrium temperature. But what if I'm exposed to steaming hot water, or freezing cold ice? How does my body maintain its equilibrium temperature then? Let's see. I'll cover myself with ice packs, and see how my body reacts. Five cold minutes later, let me check my body temperature. Sure enough, it's still near normal body temperature, homeostasis in action. Within a degree or so 98.6 is still considered normal. And despite how cold I feel, I haven't actually gotten any colder. How did my body do this? It made me feel cold, and want to wear myself up by shivering, little muscle movements that generate heat. See how pale my arm looks? After noticing the cold, my body directed by blood to my core, and less to my skin and extremities. My arm quickly loses heat to the cold environment, but the temperature stays constant in my core, which is thicker, so it loses less heat to the environment. I also get goosebumps, where my hair stands on end, creating an insulating layer like the jacket my body wisher I were wearing. So my body uses a lot of tools to keep my temperature up. When my body senses that it's cold, homeostasis mechanisms make me shiver, draw blood away from my skin, and give me goosebumps. These make me warmer, so my core temperature isn't changed. My body uses some of the opposite tools to cool down. It directs blood to the surface to cool down, making me a bit pink. It needs to resort to more extreme measures if I want to be active in the heat, because moving my muscles uses energy and lets off heat, sort of like shivering to keep warm in the cold. But in this case, my body needs to counteract the warmth that the movement causes. My body makes me feel exhausted, urging me to stop running in place, but that's not enough if I'm excited to be running for some reason. It also makes me sweat. In order to get the energy to evaporate into the air, sweat pulls heat from my body, and this helps me cool down. Not all animals have as effective sweat glands as people do, so people can endure longer periods of intense activity than many other animals. When I got warm, homeostasis mechanisms let my blood move near the surface of my skin, and made me sweat, so I got cooler. There are other forms of homeostasis to regulate things besides temperature. For example, when your blood pressure drops suddenly, which can happen if you stand up suddenly, your blood vessels constrict, which brings your blood pressure up to normal. Also, if your blood sugar rises, which can happen after eating, your pancreas releases insulin to lower your blood sugar back to normal. Diabetes is the disease that affects your body's ability to maintain blood sugar homeostasis. In general, homeostasis is when our bodies recognize a slight drift from healthy conditions, and counteract that drift by nudging us back to equilibrium.