The Body Beautiful

Human Physiology and Anatomy is something I've always had a bug for, in one capacity or another.  I had a couple years  in my 20s where I worked out with weights- and from there, learned a little bit about Human Anatomy. I knew about the upper back muscles, called Latissimus Dorsi; the shoulder muscles, called Deltoids, which are three bundles of 7 strands- called Deltoids because of their triangular shape, which resembles the Greek letter Delta. 

All this information was gotten  from Muscle Mags, which I read at the time. As well as useful data and advice, they were interesting from a sociological point of view, being a most unique 'sub-culture' with its cast of characters and various intrigues. 

But as far as any great muscular development, I just wasn't the right guy for the job. I am a mesomorphic ectomorph, a skinny-boned person who can put on some muscle- but not a lot. Unless you've got the genes, there's only so much you can do to improve your physique. With that realization, it kinda fell away.

But as far as learning more about the human body, that has continued over the years, off and on. Always adding new information, or deepening my understanding of what I already know, a little bit at a time. 

In retirement, having all this spare time and energy, I've hit it harder. I still have yet to buy a full-fledged textbook, but I do have a Gray's Anatomy and a couple study guides, plus whatever I can find online-which is actually quite a bit. So here are some of the things I've learned over the past couple years.

First, some basic stats. There are 3 different kinds of muscle in the body: smooth, which lines the stomach; cardiac, in the heart; and skeletal or striated- what we normally think of as muscle. You've got some 640 such muscles in the body. The striation is due to two active proteins: actin and myosin, which come together when the muscle contracts. 

A side comment here on medical terminology. Much of it, as far as etymology, either comes from Greek or is eponymous- named after who discovered it. Protein comes from the Greek word proteus, meaning 'holding first place'. Muscle is from a word meaning 'mouse'. 

Okay. More stats. The body has some 206 bones(Gray's says 200)of various shapes and sizes. The largest, or longest is the femur, or thigh bone. Smallest is the tiny hyoid bone, underneath the tongue. Your bones are made up of concentric circles, called Haversian Systems, each of which has a small hole in the center. Inside the bones are red marrow(which turns yellow as we age)which produces blood cells, and also minerals and other nutrients. 

There are over 200 different kinds of cells in the body, but three different kinds of blood cells: Erythrocytes, or red blood cells; Leukocytes, or white blood cells; and Thrombocytes, or platelets. 

Red blood cells oxygenate the body. They contain a pigment called Hemoglobin, which binds loosely with oxygen. Hemoglobin is also what gives Caucasians that pink glow to their skin. They come from the bone marrow, and also are produced by the Liver. 

White blood cells, also called T-cells, have to do with our Immune Systems. They come from an organ called the Thymus, which is in the chest. Also called Leukocytes- too low or too high a count indicates Leukemia, which is cancer of the blood.

Platelets have to do with clotting, or coagulating the blood- solidifying it when an injury(cut)has taken place. Blood in the body also has a solid form in addition to the liquid form we know as plasma. 

There are cells in the body designed to clean things up, who go around eating up dead cells and other waste- called Phagocytes or Macrophages(meaning 'big eaters')much like Spiders cleaning up other insects. You also have cells which don't initiate but assist once something is underway. I guess you could think of this in MTM terms, and call them "Millie Helper" or "Murray Slaughter" cells. 

This is a vast subject, even for one who knows as little as I do. All too easy to get caught up in minutae. There are 19 muscles in the forearm, which I don't know individually except that they are either flexors or extensors. Basically, the body is made up of a number of operating systems. 

The Central Nervous System is the brain and spinal cord. 12 sets of nerves in your noggin(Cranium), all to do with basic senses: seeing, hearing, smelling, tasting. Kinda like an old telephone switchboard with all those 'wires', running through holes in the skull called Foramini(singular is Foramen)Attached to that is the Peripheral Nervous System, which is the rest of the body. 31 sets of nerves.

The Autonomic Nervous System is all the 'involuntary' stuff like heart rate, blood pressure, body temperature and is divided into the Sympathetic and Parasympathetic nervous systems, which actually work in opposition to one another. It is overseen by a part of the brain called the Hypothalamus, which connects it to the Endocrine System- which is the stomach, pancreas, thyroid, kidneys- all those organs which secrete their chemicals directly into the bloodstream, without going through a duct or other opening. 

Hooboy. Okay, the Hypothalamus regulates hunger, thirst, perspiration, and sexual excitement, and in addition to being the link between the Autonomic Nervous System and Endocrine System, oversees the Pituitary Gland and sends instructions to it- their relationship is  kinda like a Principal and Vice-Principal. In the case of dehydration, there are Sensory Neurons(nerve cells)in the Hypothalamus which are alerted, sending a message to the Pituitary to release Anti-Diuretic Hormone to retain the body's water until such time as the body is hydrated again.  

Amazing all the chemicals that are at work in the body. The pituitary gland, near the base of the skull,  called the "master gland" in that it oversees the other Endocrine glands, is about the size of a BB. But it contains 9 different chemicals. Seven in the anterior and two in the back. 

So much stuff here. I didn't even get to the various other operating systems- such as the Integumentary System, which is your skin, hair and nails. Or some of the other chemicals or neurotransmitters in the Brain, like Seratonin or Dopamine. Or other parts of the Brain like the Hippocampus and Amygdala. Or the various sutures that hold the skull together: Lamboidal, Sagittal, Coronal, Parietal.

Or a whole lot of things. Reading up on this stuff is always a humbling experience, in that with every new thing I learn begets ten more I don't. Mr Know-it-all is reduced to Mr Don't-know-a-damn-thing-about-nothin'!

But humble can be a good thing. If I had it to do over again, I might well have chosen something in the field of medicine.   It's fascinating, at least to me, and is something that at least purports to help people. Ease human suffering, and all that good stuff. Dr Roundly. 

Maybe next time around.. 


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