Posts

Showing posts from August, 2017

Lucky About Renin

Image
Our blood nourishes and oxygenates every cell in our body. But that blood could not reach those cells without a pressure behind it, forcing it through our body. Just as important, if that pressure decreases too much and for too long – minutes in some cases for the brain and heart – death will occur. So, it just so happens, through a series of physiological events far too complicated for our purposes here, the body maintains blood pressure within a relatively narrow range. One of the ways it does this is through a hormone (renin) produced by the kidneys. For the sake of simplicity, when the kidneys sense a decrease in circulating blood volume (a low circulating blood volume translates into low blood pressure), they secrete renin. Renin travels through the blood system to the liver where it is converted to a substance called angiotensin 1. Angiotensin 1 then travels to the lungs where it is converted into angiotensin 2 (A2). Here is where it gets down to the business of increa...

60,000 Miles

Image
If you could stretch out the blood vessels in the average adult, it would circle the earth nearly three times. What an astonishing bit of evolutionary accident for all those vessels to derive from a single fertilized ova. Or, it all was planned and initiated by the Creator. Human Circulation

Heart Throb

Image
The heart is divided into four chambers. The upper two are called the left and right atria. The bottom two are the left and right ventricles. In the normal heart blood is pushed (pumped) from the atria into each respective ventricle. The ventricles then contract to eject blood into the circulation. The heart muscle itself is unique of all the muscles in the human body. Only in the heart can cells initiate their own electrical discharge. It’s a process called ‘automaticity.’ As the electrically charged ions (potassium, sodium, chloride, and calcium) move into and out of each cell, they initiate an electrical impulse. Unless those electrical discharges could be better utilized, nothing more than a ‘twitching’ would occur in the tissue around each cell. Life, however, could not exist if nothing but a ‘twitching’ occurred in the heart. What the body needs is a coordinated ‘contraction’ of an entire set of cardiac muscle to pump blood from the heart into the body’s circulatio...

Exhaling for Life

Image
Carbon dioxide is the natural byproduct of cellular metabolism. As most people know, we inhale oxygen from the air around us and exhale carbon dioxide (CO2). Everyone knows why we need to inhale oxygen, but not many know why it is important to life that we exhale CO2. That’s the focus of today’s post. CO2, when combined with the water in our blood, becomes carbonic acid. As carbonic acid builds up in our blood system, the acidity of our blood increases. But there is a limit as to how much acidity our body can tolerate. A significant increase for too long – an hour or less in many cases – will kill us. One the other hand, too little acidity in our blood for too long will also kill us. Now here is where we are either the product of an extraordinary chain of lucky evolutionary events – or we are the product of an extraordinary intelligent Creator. Near the part of our brainstem called the ‘medulla’ are specialized cells called chemoreceptors. Those cells respond to changes in ...

A Corrosive Stomach Environment

Image
Your stomach acid has a pH of around 2.0. That’s the same pH as hydrochloric acid (HCL). Put a few drops of HCL on your kitchen table and it won’t be long before you have a hole in the table. The reason our stomachs need that low a pH is beyond the scope of this simple post, but I hope you will wonder WHY that extremely corrosive acidic environment in our stomach doesn’t dissolve our stomach. One reason has to do with the mucous cells lining our stomach wall. They serve as a protective coating to prevent that from occurring. So, think about this: It is either an astounding bit of luck in the course of our evolutionary development that the mucous cells exist in our stomach . . . . Or those cells were specifically designed by our Creator to protect the stomach from being dissolved by the acid.

No Scientifically Sound Third Option

Image
According to medical research, an average of 250 million sperm are released every time a man ejaculates.  250,000,000 sperm in EACH ejaculate. And each one of the 1/4 million has its own unique DNA coded into it. That means n o two sperm have the same DNA code. As most every adult knows, DNA directs our formation in the womb regarding our gender, basic intelligence, eye, hair, and skin color, our eventual height, what medical issues we will be susceptible to – and an uncountable number of other elements unique to each individual man and woman. And, of the hundreds of millions of sperm cells racing toward the mother’s ova (egg), only ONE will successfully break through the ova’s coating and bring about what we know as the conception of a singularly unique person. In other words, you and I are each a one-in-a-quarter of a million possibilities. When we take the time to think that remarkable bit of biological science through to its logical conclusion, we are faced with on...