Homeostasis is a key concept in biology. The concept of homeostasis is the description for when the internal conditions of living organisms remain stable (within a normal range), regardless of what is going on in the external environment. These internal conditions include your body temperature, pH level, and glucose level.
Homeostasis attempts to maintain your system in a normal range; if toxins would build up in your system, homeostasis would be disrupted, and you would become very sick.
Homeostasis and metabolism
Each cell in your body is actively involved in metabolism, which basically is the process of using nutrients from food to provide fuel for cellular processes. Metabolism is like a wood-burning stove that heats a home (your body). Food is like the logs that are thrown on the fire.
When logs burn, ash is created. Ash is the waste created from the using of energy. If the ash is not removed from the fireplace, eventually the fire can no longer burn. When food is broken down, as much of the nutrients as possible are used to fuel the body. After as much energy as possible is extracted from food through digestion and metabolism, the remainder is excreted, or removed.
Suppose that it’s really cold outside — snowing even — and you run out to your mailbox in a short-sleeve shirt. While you’re out there, a neighbor stops by to chat. Your body wants to maintain its body temperature around 98.6°F. Your skin senses the cold conditions outside, and nerve impulses are sent from receptors in your skin to your brain that say, “Hey! It’s cold out here!!”
In an attempt to stay around 98.6°F, your body makes adjustments automatically. Goose pimples form, which actually are the hair follicles on your body tightening to make your body hair stand up higher to help insulate your body. If that doesn’t help to maintain the normal temperature, you start to shiver. Shivering is an attempt by your body to create heat through movement.
If your chatty neighbor is still rambling on, and shivering doesn’t help keep you warm, your body’s “thermostat” will begin to drop (if it goes too far, hypothermia begins), and your “furnace” will kick on to create heat internally so that homeostasis — maintaining relatively normal values — occurs.
Homeostasis and disease
Disease occurs when homeostasis can’t be achieved. Suppose that your chatty neighbor spread the flu virus to you when he sneezed during your conversation. Your body needs to fight off the invading virus, which likes living at your normal body temperature. At 98.6°F, the virus can happily reproduce, making you sicker and sicker.
Your body wants to be in homeostasis, but if it maintained normal body temperature, the virus would take over your entire body. In defense against the virus, your body temperature rises above the normal range (fever), which makes your body an uncomfortable place for the virus to live. The virus slows down in the hotter temperature, which allows your immune system to attack it.
The fact that your body temperature goes above normal (fever) means that homeostasis is disrupted, and that indicates disease (the flu). Once your body has effectively suppressed the viral attack, the fever “breaks,” and your body temperature returns to normal. The disease state is over, and homeostasis returns.
Remember that fever is a natural, healthy process. If you develop a fever, let it do its job of making your body inhospitable to a virus or bacteria. Don’t quell the fever with aspirin, ibuprofen, or acetaminophen right away. If the fever continues for days, though, you should see the doctor.
A fever caused by a virus usually breaks on its own as your body fights the virus. However, an infection caused by bacteria requires an antibiotic to help your body fight. The fever associated with a bacterial infection usually is higher and lasts longer than a fever caused by a virus.