Homeostasis

                 Homeostasis and other Miracles 

In some of my essays, I've tried to describe what I think are the true miracles we all live every day. And, yes, life itself is a miracle. Looking at flowers, trees and animals, I see that they also represent myriad miracles and I am in total awe. 

They may not speak as we do but, like us, they are born, breathe, eat, grow, heal, reproduce and die. They have intricate internal mechanisms that provide them with all the senses they need to survive until it is time for them to die. We do too.

The very same intelligence that we have within us, is designed into them, as well. We, and they, don't have to think about what to do in a given situation. All of life is designed with an automatic response system on board - another miracle.

Without thinking, an injury is sensed and an automatic healing process is begun. In the case of trees and plants, they have an additional miracle of being able to regenerate damaged or lost parts, allowing them to survive. Experiments have shown that plants will also register reactions to fear and pain. 

Our automatic system is designed for our survival. When we have an injury, our brain immediately sends messages synthesizes chemicals and sends them to the spot that is hurt and begins the miracle of healing. 

When we are frightened or challenged our brain will automatically produce and deliver the chemicals necessary for us to defend ourselves or to run away (the fight or flee response). 

All of these examples of miracles are amazing. I want to tell you about another miracle named, Homeostasis. It is intriguing because it is the one miracle that makes all the other internal miracles possible.

The term was coined by Walter B. Cannon, the great Harvard physiologist. He used it to describe a particular internal system contained within our bodies. This incredible mechanism makes it possible for us to go about our lives without the need for conscious concern.

Homeostasis is the ability of the body to stay in balance and under regulation. A host of automatic responses are controlled this way so that we don't have to think about what to do. It's easy to imagine Homeostasis as an internal engineer, compete with a detailed plan to control our survival. Let's look at an example of homeostasis in action.

The ability to regulate the body's temperature is done quite effectively. Homeostasis makes sure that we will not get too hot or too cold (within our survival limits). In an effort to maintain stability and balance, it operates as a safety device - a preset internal thermostat. 

For instance, when we are getting too hot, the system reacts by opening the pores. This allows the perspiration to exit and creates additional skin surface making the process of evaporation more efficient. This cooling of the skin will help bring the internal body temperature back into balance. The rate at which we breathe will be reduced to limit the amount of heat generated by oxidation (respiration).

Additionally, there will be an involuntary relaxing of the muscles and a tendency to spread our extremities and to lie still. These automatic moves and urges are designed so that we are limited in our ability to generate heat.

Conversely, in situations where we are faced with very cold conditions, there are other responses that will be activated to maintain our balance. First, the pores will close tightly, reducing the amount of skin surface exposed to the cold. Our breathing rate will become more rapid allowing more fuel (oxygen) to be burned for heat (oxidation). All our muscles will be contracted in an effort to prompt movement which will produce some heat. If the cold continues and we do not, or cannot, start moving, involuntary movements will begin, what we call shivering.

Homeostasis simply insists that we must survive. So it's efforts continue. The hair on our bodies is made to stand erect in an effort to contain body heat. This is a primitive duplication of the same thing done by fur-bearing animals. We will find ourselves automatically curling up into a fetal position so as to reduce the amount of exposed surface thus conserving the body's core heat. 

This homeostatic mechanism tries very hard to keep us alive in both extremes of temperature. We don't have to think about it or have to decide what changes must be made - it is all done for us, automatically and efficiently. It is one more example of the many miracles we live with every day. In our body, a major miracle itself, Homeostasis is the miracle within.