When talking in technical terms, homeostasis can be confusing to some students. The goal of this study guide is to put the concept of homeostasis into terms and uses that you can understand. It's really not a difficult concept to grasp once you see it in motion or the act of it is pointed out to you.

Definition

Homeostasis is simply a systems way of maintaining balance and functionality. Various systems are in place that each play a role in regulating the body. For instance, when you have a fever your body sweats but you are cold. You are cold because the temperature outside your body is cooler than your body temperature and you sweat as the body tries to bring its temperature down.

Body Regulation

But temperature is not the only thing that's regulated. There are multiple systems working together to regulate all functions of the body at all times. Look at some of the examples below to explore some of the ways our bodies regulate themselves.

• Diarrhea and vomiting. This is the bodies way of ejecting things that the body feels is unhealthy for one reason or another. This doesn't mean that every time you eat something unhealthy your body is going to eject it. Your body can withstand a certain amount of toxins before it has to expel them. For example, if a person consumes too much alcohol they will vomit as the body rejects an overload of poison to the system. When you're sick, the body is focusing on trying to kill the bacteria or overcome whatever virus made you sick. You may expel fluids as the bodies way of eliminating overload. This is to say that the body cannot handle the process of digestion because its focus is elsewhere.
• Breathing. The body needs oxygen to live. Your brain sends signals to your lungs when you need oxygen that tell you to breathe. This is another form of homeostasis. It is the bodies way of regulating the amount of oxygen in the system.
• Response to stimuli. When you experience something harmful, your nerves send a signal to the brain that is telling the brain something is potentially damaging the body. The brain sends signals to the body to move away from the danger. This happens in a fraction of a second. Hence, the jerking reflex that moves your body or body part out of the way of danger.
• When you are active, the brain recognizes that energy is being consumed and must be replenished. In response to the signal from the brain, the heart begins to beat faster and you may breather harder. It simply means that the body is trying to maintain homeostasis by replenishing what has been used.

Example

Consider your home as a system. Go to the thermostat in your home and see what it is set on and what the temperature in your home is. Is the air conditioning on? Is the furnace on? The thermostat responds to the stimuli of the air around it. If the air is too cold, the thermostat sends a signal to the furnace that it is needed. If the air is too hot then the thermostat sends a signal to the air conditioner that the air needs cooled. The air conditioner or furnace kick on until the thermostat tells it that the temperature is a the proper level.

So what happens if one of these systems doesn't work correctly? In humans when the system does not work correctly, other systems may pick up the pace in some respects to try to maintain homeostasis. For instance, let's assume you are allergic to wool. For whatever reason your body does not respond well to wool. When you get near it, your body breaks out in a rash or hives. This is one way of the body warning you that something is not right.Your instant response is going to be avoiding the wool.

Our bodies send us signals all the time that we process consciously as well as subconsciously. You don't have to think about breathing to do it, but you do have to think about eating to do it once your body tells you that you are hungry. Paying attention to the homeostasis of your own body by keeping track of your vital signs is an excellent way to begin to learn to read some of your bodies generally unnoticed signals.