My favorite class in college was Anatomy and Physiology. We learned the basics of how the human body operates. When one studies the human body, it is typically broken down into various body systems like the cardiovascular, respiratory, endocrine, and neurological systems. When we discussed the cardiovascular system, we learned about the incredible muscle strength of the heart, and its four valves that operate seamlessly to ensure that your body is receiving vitally needed nutrients with every heartbeat. Did you know that an 80 year old person’s heart could potentially beat over 3 billion times in its lifetime?! When we analyzed the respiratory system, we learned about the delicate gas exchange of oxygen and carbon dioxide that occurs in the lungs with every breath of air that one takes. The endocrine system is yet another delicate system of checks and balances; anyone who has diabetes or has a family member with diabetes knows the importance of the hormone, insulin, in regulating blood sugars.
The neurological system is the one that I will highlight the most for you. Did you know that the average brain weighs about 3 pounds? There is a principle called the Monroe-Kellie Doctrine that essentially says your brain is composed of 80 percent brain tissue, 10 percent blood, 10 percent cerebrospinal fluid. If there is an increase in one of these components without a corresponding decrease in another, you are at risk for increased pressure in your brain. In the intensive care unit, the doctors will sometimes insert a tube into a person’s ventricles (spaces in their brain) to help drain out some of the cerebrospinal fluid to allow the brain to not have too much pressure and thus reduce the risk of neurological damage. Another cool fact about the brain is that you have 12 cranial nerves. These cranial nerves help you see, hear, feel your face, and see. So next time you are eating a bowl of cereal, be grateful for your trigeminal nerve, the 5th cranial nerve, that helps you chew.
As a Christian, studying the body is like seeing God’s handiwork up close and personal. He is a God of such detail, order, and process.
I said all that to say even though we know so many things about our bodies through science, my favorite line in the Anatomy and Physiology book was something completely different. There was literally a line that said something to the effect, “It is not known what function this [fill in the blank cell] performs.” Our God, the Creator, is an amazing and creative God. There are so many cool things that we know about the body, but we still do not know everything. There are still things that are yet to be determined by us.
God is the God of the known and the unknown, both in our bodies and in our very lives. Psalm 139:14 reminds us, “I praise You, for I am fearfully and wonderfully made. Wonderful are your works: my soul knows it very well.”