The Cell: Prokaryotic

The Cell: Prokaryotic

Before going any further in my ongoing series about the inner workings of the cell, I felt I should pause and discuss an underappreciated and relatively unheralded type of cell: the prokaryotic cell.  Prokaryotic cells differ widely from the eukaryotic cells we previously discussed. This article will offer a brief overview of prokaryotic cells and discuss their place in the origins debate.

Prokaryotic cells are vastly different than the eukaryotic cells discussed in the previous article on cells.  The biggest difference is in DNA storage. Eukaryotic cells store DNA tightly coiled in the nucleus.  Prokaryotic cells store DNA in strands found randomly throughout the cell and lack a nucleus entirely.  Instead, the DNA strands are stored in areas of the cytoplasm called nucleoid regions.   Prokaryotic cells also have cell walls, which are found only in plant eukaryotic cells.  Some also have an additional outer layer called a capsule.  The capsule is designed to prevent damage from other organisms intestinal tracts as well as retain moisture.  Most prokaryotic cells also have structures on the surface called pili. Pili can be used to attach to other bacteria, or to surfaces, depending on their design and length.   Prokaryotic cells do have ribosomes to synthesize proteins just a eukaryotic cells do. However, they have no other cellular organelles.  What they do have, however, is an extra set of DNA called plasmid DNA. Plasmid DNA is a circular strand of DNA which does not code for reproductive information. Instead, it functions as storage for various traits.  Some prokaryotic cells also have flagella, which are used for locomotion.

Prokaryotic cells reproduce much differently than their eukaryotic counterparts. Instead of reproducing sexually, most prokaryotes reproduce asexually through a process called binary fission.  Binary fission is a fairly straightforward process. The DNA strand duplicates within the cell and the two strands attach to the cell membrane.  Once this occurs, the cell membrane begins to grow until it has doubled in size. This done, the membrane begins to compress in the middle, eventually pinching off into two separate cells. However, there are other methods of DNA transfer. The first is conjugation. This is where the plasmid DNA becomes useful. Prokaryotes will sometimes exchange pieces of their plasmid with one another. This allows for information exchange without uncoiling the DNA strand. More infrequently, the prokaryote will take in DNA from the surrounding environment. This DNA comes from damage viruses, destroyed prokaryotes and sometimes eukaryotes as well. This is called transformation.

Prokaryotic cells are an interesting afterthought for many students of biology, but it is estimated that there are trillions more Prokaryotic cells than Eukaryotic cells in this world. This is due to the fact that the vast majority of single-celled organisms, such a bacteria, are prokaryotic cells. Many prokaryotic cells are also known as extremophiles because they live in extreme environments such as volcanoes and high saline water, even though these areas are completely inhospitable to any other life form.

Now that we know a little about prokaryotic cells, the time has come to discuss how they fit into the origins debate.  Evolutionists claim that prokaryotic cells were the first cells to develop and that eukaryotic cells sprang from them. This argument has several issues with it. The first is the question of how the first prokaryotic cell came into existence.  Even though it is far less complex than eukaryotic cells, prokaryotic cells are far from simple.  They may lack ribosomes, but they have other features, such as cilia and flagellum which are complex. In fact, flagella are so complex, they are the prime example of irreducible complexity.  Further, prokaryotic cells have plasmid DNA, something completely lacking in eukaryotic cells. The origin of each of these parts must be explained, individually. The prokaryotic cell is extremely complex and cannot be explained by evolutionary thought.

The second issue is how did a eukaryotic cell, with its numerous organelles, spring from a prokaryotic cell which lacks organelles? Without listing them all, here are a few differences between the two cells. Eukaryotes have multiple distinct types of organelles. Prokaryotes have none. Eukaryotes have a nucleus which contains its DNA, whereas in prokaryotes it is not bound up in a nucleus. Prokaryotes have plasmid DNA. Eukaryotes lack this feature entirely. The list goes on.  By what mechanism did these differences arise? How did eukaryotic cells diverge so far from prokaryotic cells? And why are there no intermediates between the two? Evolutionists must answer these questions.

Creationists can easily explain the existence of both eukaryotic and prokaryotic cells. Both were designed by the Master Designer to function just as they do in the modern world.  Neither type of cell has to come from the other in the creationist worldview. God made both, separate, and distinct from one another.

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