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C r e a t i o n  I n d e x

C r e a t i o n  p a g e  4 0

Prokaryotes have several structures sticking out from them; hairlike pili.(function largely unknown).and bacterial flagellum.(bacteria that swim which have propellor like movements).used for locomotion. This motor turns the  long, helical.flagellum.propelling the cell through its environment.

Eukaryotic cells contain a number of subcellular spaces that are separated from the cytoplasm by their own membranes. These are called organelles, which allow this cell to conduct specialized functions in specialized compartments. One specialized organelle is the nucleus containing the cell's DNA.

Many other fascinating parts for cellular functions occur. The 'simpler' prokaryotes include; nuclear pores, mitochondria, lysosomes, endoplasmic reticulum, with its smooth and rough sides, Golgi apparatus, cytoskeltons with its microtubules.(made of actin, a specific protein).and its protein filaments.comprising three different thicknesses, like three gauges.(sizes).of wire; macro filaments and intermediate sized filaments, mitotic spindles, chromosomes.(and in the case of plants, added to these prokaryotes is cholorplast containing chlorophyll), vacules, covalent hoarding of atoms to form molecules with their compositional materials, amino acids, proteins.(which typically contain 50 to 3,000 amino acids), nucleic acids with its parts, either ribose.(RNA).which has a composition attached made from specified combinations of its 4 bases, being adenine, cytidine, uracil and guanine, or deoxyribose.(DNA), which similarly has adenine, cytidine, guanine and thymine.

Uracil replaces thymine. This design allows for the code's meaning to remain consistent for both RNA and DNA, while affecting the chemical mechanisms. It's like typing a word with one letter in a different font, CAR as compared to car. The information is clear, the meaning remains the same; yet the composition varies, there being more chemicals.(ink, if this was paper).in this composition.(CAR).than in this one.(car or Car).

An amino acid side chain gives an amino acid its particular character. It is the particular shape of a folded protein and the precise position of the different kinds of amino acids that allow a protein to function in the various ways it does.

Complexity is evidenced in the 'enzyme sacks' called bacterial cells.(prokaryotes). Here there are many levels of subcellular organization, for example; a typical Escherichia coli cell is surrounded by two membranes enclosing a periplasmic compartment that is used for acquiring and sorting nutrients and wastes. The center of the cell contains DNA strands folded into a compact nucleoid, forming a loosely defined compartment devoted to storage and use of genetic information. The cytoplasm occupies the remaining portions of the cell and is filled with ribosomes and many different enzymes. Many proteins are formed into complexes and thus enabled, subsequently engage in many tasks. Some of these complexes combine several tasks to increase efficiency. For example, molecules are delivered step to step by the use of a flexible arm.

Proteins are created and folded and old ones are dispensed with, thanks to the functioning chaperonins and proteasomes.
    This is.extremely complex and requires highly efficient coding.

There is astonishing complexity involved in how DNA polymerase.(a polynucleotide).is the repository and copying factory of genetic information, telling the cell how to make polypeptides

How does a cell know when to transcribe a gene? How does it select a specific gene from the thousands available? How does the information get transferred from one 'polymer' language to the other?

A cell makes an RNA copy of a small portion of its DNA.(called a gene).by a process called transcription which codes for a protein.(a special protein is manufactured using the DNA code).and by a process termed as translation, whereby the information in the RNA is used to produce a protein by latching onto DNA at a binding site that it selects for utilization of a particular sequence

The transcription of a gene entails numerous decisions, one being where along the DNA chain to start. This complicated, fascinating and mysterious process involves balance of functioning, as when transcription is in process.(forming), it becomes overwound, yet automatically corrects by cutting strands of overwound DNA, passing the uncut strands through the cut strands and then resealing the cut. Transcription stops when the RNA runs into a special DNA sequence.

In DNA replication, a great deal of effort is required in cell division to ensure the genetic information be copied and handed down uncorrupted. Tasks are necessary to ensure accuracy in the copying of the two parent strands and their separation and unknotting as they form. Enzymes repair DNA damaged by ultraviolet light, chemical mutagens, or other environmental insults. The enzyme complex polymerase unbinds the nucleotide double helix of the DNA.


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