There are two universes‚ one is external to our body and one is internal to our body. Both are infinite in complexity and size.
None of us knows how great the external universe is, nor how old it is, nor if there are more universes beyond the universe we call “Our Universe.” We only know that we are present within “Our Universe” and that we shall live and die here.
Strangely enough, we have the same mental confusion with our own bodies. At first glance, our bodies seem quite ordinary. We see arms and legs and other parts, we breath, we talk, we eat, we run and our bodies appear to be routine and non-complicated until we look closer.
BLOOD CIRCULATION–MACROSCOPIC VIEW
Then we see the inner universe. The universe of a sea of blood and one hundred trillion cells. Looking through our imaginary microscope into our body we see that the one hundred trillion cells never sleep. They work constantly, day and night, creating thousands of molecules which they extrude into the sea around them.
They are constantly taking in molecules of oxygen and other nutrients, hormones, minerals and immune products–churning them within the various chambers of the cells and producing molecules with high energy bonds to be used by other cells and, simultaneously, releasing waste products that are deadly to the cells that produce them and to other surrounding cells.
Then we note that almost all these cells are attached to each other by strange looking fibers that run from one cell to another through the sea of blood. These fibers are elastic and give way with pressure from the external world, but then pull back when the pressure is released. If we squeeze our skin we can see them stretch and then recoil and the original position of our tissue is replaced.
In babies, there many more of these fibers than in adults, and their skin and tissue is elastic like rubber balls.
When we look at our bones we also see our living cells. They are hidden in caves which lie along rivers and canals of crystals. But, they too, work just as hard as the others, handling the products that the blood brings them and releasing their toxic by-products.
Everywhere we look, we see cells floating in the sea of blood, but tethered to each other by long threads of protein material, some elastic, some made of collagen and some made of a weird material called proteoglycan.
Thus, they float and consume nutrients, operate their tiny factories and spit out useful products and pollutants.
We, of course, are oblivious to everything they do. The only time we are aware that we own a kingdom of one hundred trillion cells is when they stop working. Then we die.
THE SEA OF BLOOD
Our cells are floating in a sea of blood. But, looking down through our microscope, it is very hard to think that the messy solution before us is blood.
We can see millions of small round cells, that are red and have a dimple in their bellies. These must be the erythrocytes, or “red cells” that everyone talks about. But they are in a minority in terms of the total volume of blood.
There are millions of other articles floating around or dissolved in the salty solution that holds everything. White cells of every shape and size, platelets that look like pieces of pizza, grotesque cells that have just escaped from the bone marrow, killer cells, target cells, and countless other jetsam moving slowly about, but always in one direction.
We know, without seeing them that billions of atoms and molecules of minerals and proteins and fats and sugars are also in the blood. The list of everything in the blood would make up a fat book called Hematology.
CELLS AND BLOOD MOVING
One thing cannot escape our attention, most of the cells are tethered, but many are moving. These are the red cells and the white cells of the blood stream. Other objects are moving as well and they are moving in two directions.
One group is moving quickly in one direction, and the other group is moving slowly in the opposite direction. But the volume of the quick movers is equal to the volume of the slow movers.
THE TWO PUMPS
Instinctively, we know that the flow of blood moving quickly is coming from the Heart.
The Heart is the master pump of the body. It forces all blood to every cell in the body. The heart uses a group of tubes called Arteries to carry that blood to every distant cells.
Once the blood has arrived at the cell, the cell removes the oxygen and all nutrients and all other ingredients and utilizes everything in its metabolism.
When finished, the cell disgorges by-products and new products and waits for the next shipment. In the sea around the cells there is “used blood.” Blood filled with waste material which must be removed from the body or all the living cells will die because of the pollution.
We might say that our cells are like our cities which would die if there were no sewer systems. Our sewer system is much like that of a city’s sewer system.
Our polluted blood is taken to sewage disposal plants where it is cleaned and subsequently reused. But, first our polluted blood must get back to our heart in order to be transported to the sewage plants. How that used blood gets back to the heart is an interesting story.
We will see that process in the next Chapter.