Hi guys. Sorry for the lack of posts as of late. Recently, I began to have some problems with internet in my home and I am working on getting it back so I am able to post regularly, once again. With that, I’ll jump right into today’s discussion.
In my last post I got started on a discussion about DNA and the evolution of life on planet Earth. In this post I will continue that discussion. A good place to start might be with the basic properties of cells. Each numbered point may be a little lengthy so I may do these as separate posts to keep things from being too long.
Cellular activities require a great bit of organization, consistency, and precision. Understandably, the more complex something it is, the less room there is for mistakes to be made. This is evident in that there is an error rate of less than one out of every ten million nucleotides incorporated in duplication of DNA. And even when these errors are made, an elaborate repair mechanism is employed for the defects (Karp 2013).
Another thing to note about the consistency of cells is that, through the use of high-powered electron microscopes, scientists have discovered that organelles and other cellular structures have a particular shape and location, for all individuals of a species. Making up these organelles is a set of macromolecules, which are arranged in a pattern that is so concise as to be predictable (Karp 2013).
To understand this concept a little better, let me use an example. We all have cells in our intestines that remove nutrients from our digestive tract. These cells are known as epithelial cells, and inside of all of us they are connected to one another the way that bricks making up a wall might be (Karp 2013).
Facing the intestinal channel are the apical ends of the epithelial cells. The have microvilli, which aid in the absorption of nutrients. The microvilli have the capability to project outward from the apical cell surface. They are able to do this because they, the microvilli, are made of an internal skeleton made of filaments. The filaments are composed of protein monomers that are polymerized in a particular array (Karp 2013).
Intestinal cells, at their basal ends, contain large numbers of mitochondria that provide the energy that is needed in order to fuel processes involved in membrane transport. Each of the mitochondrion contained in these intestinal cells also have a deeper level of continued organization, being that they are composed of a defined pattern of internal membranes. These internal membranes are composed of proteins in a consistent array. This includes a machine projecting from the inner membrane that is electrically powered and synthesizes ATP (Karp 2013).
Amazingly, though it is easy to point out dozens of differences between a human and a cat anatomically, at the cellular level, their organelles retain many similarities. When scientists do research on cells of one organism, it is not uncommon for those findings to be applied directly to other species and other forms of life. All living organisms carry out a number of processes very similarly. Among these are protein synthesis, conservation of chemical energy, and membrane construction, to name just a few (Karp 2013).
A prospective medical student, looking to help others succeed.