Dna Polymerase : Gene Expression, Transcription And Translation Essay

Transcription is the formation of an RNA strand from a DNA template within the nucleus of a cell. There are four nucleotides of DNA. These are adenine, cytosine, guanine and thymine. These nucleotides are transcribed to form messenger ribonucleic acid (mRNA) consisting of nucleotides made of adenine, cytosine, guanine and uracil. This transcription from DNA to mRNA happens by an RNA polymerase II. This newly created mRNA is read in the 5' to 3' direction in sets of 3. These sets are called codons. Each mRNA also has a cap and end. On the 5 prime side is a methylated guanine triphosphate and on the 3 prime is a poly A tail. Messenger RNA then moves to the cells cytoplasm and through the cells ribosomes for translation. Messenger RNA is matched to molecules of transfer RNA (tRNA) in the ribosomes to create amino acids. These amino acids subsequently form an amino acid chain. (Osuri, 2003) A visual representation of this can been viewed in figure 3.

1) DNA programs protein production in the cytoplasm by transferring its coded information to a molecule called RNA (mRNA). The RNA then carries the order to build this type of protein from the nucleus to the cytoplasm.

Since DNA has the instructions for making protein we usually wonder how is it able to make ribosomes if DNA is stored within the nucleus. This is when a handy tool comes in called transcription and copies the DNA into mRNA so it can be reached outside of the cell.

DNA per medical dictionary is defined as A nucleic acid that carries the genetic information in cells and some viruses, consisting of two long chains of nucleotides twisted into a double helix and joined by hydrogen bonds between the complementary bases adenine and thymine or cytosine and guanine. DNA sequences are

Translation is a task that makes ribosomes synthesize proteins utilizing mRNA transcript made during transcription. In the begining of this task mRNA attaches it self to a ribosome so that it can be reveal a codon (three nucleotides).

Each human being has something called DNA. DNA is described as genetics and an extremely long macromolecule that is the main component of chromosomes and is the material that transfers genetic characteristics in all life forms. DNA constructs of two nucleotide strands coiled around each other in a ladder like arrangement with the sidepieces composed of alternating phosphate and deoxyribose units and the rungs composed of the purine and pyrimidine bases adenine, guanine, cytosine, and thymine. Each chromosome consist of one continuous thread-like molecule of DNA coiled tightly around proteins and contains a portion of the 6,400,000,000 basepairs that make up your DNA.

Transcription is a process in which genetic information from DNA is encoded onto messenger RNA, by unwinding the DNA and splicing exons and introns and coding them onto the mRNA so the DNA itself is not used directly. Translation is a process by which ribosomes reads the mRNA to determine the amino acid sequence of the protein.

DNA is made up of genes, which are small portions of the DNA strand. Genes create cellular protein needed for the body to function. DNA not only creates cellular proteins, but also has the instructions for when and where they will be made. (Racenis 2)

(Except that uracil replaces thymine). The nucleotides form sugar-phosphate bonds with each other and become an mRNA strand but they do not form bonds with the DNA strand. The sequence of three exposed bases on mRNA, that are complimentary to the base triplet on the DNA, are known as codons. Once the mRNA strand is complete it moves from the DNA in the nucleus, through the nuclearpore into the cytoplasm where it drapes itself over the ribosomes with their codons exposed. Floating in the cytoplasm are tRNA molecules which job is to pick up specific amino acids and transport them to where the mRNA is draped.

DNA contains the genetic information for producing proteins. Firstly, the DNA coding leaves the nucleus to the cell’s cytoplasm where it is read and synthesized into a single protein. However, if a mutation occurs it affects the DNA coding for proteins. For example, Progenies was resulted by a mutation that occurred in the DNA, which caused the transcribed

DNA, Deoxyribonucleic Acid, is the basic structure for all life, it is the blueprint, the instruction manual, on how to build a living organism. DNA is made up of four nitrogen bases, adenine, thymine, cytosine, and guanine which are connected by sugar-phosphate bonds. Through a process called Protein Synthesis, the nitrogen bases are the code for the creation of amino acids. Essentially, DNA makes amino acids, amino acids make proteins, proteins make organisms. This process has been taking place for much longer than scientists have been able to document. Those scientists are called geneticists and their field is genetics.

During the process of transcription, the information stored in a gene's DNA is transferred to a similar molecule called RNA (ribonucleic acid) in the cell nucleus. Both RNA and DNA are made up of a chain of nucleotide bases, but they have slightly different chemical properties. The type of RNA that contains the information for making a protein is called messenger RNA (mRNA) because it carries the information, or message, from the DNA out of the nucleus into the cytoplasm.

One of the fundamental discoveries of the 20th century was that DNA was the genetic code’s physical structure (Watson & Crick, 1953) and, since then, many studies have disclosed the complicated pattern of regulation and expression of genes, which involve RNA synthesis and its subsequent translation into proteins.

Transcription is where DNA is transcribed into RNA which then can be pass to the ribosome’s to act as a template for protein synthesis. Before transcription can begin DNA must unwind and the two halves of the molecule much come apart so exposing the base sequence. This process begins when a region of a two DNA strands is unzipped by enzyme called RNA polymerase attaches to the DNA molecule at the imitation site.

The formation of a protein begins in the genes, which contain the basic building information for all parts of living organisms. There are four DNA nucleotides that make up genes: A, T, C, and G. A codon is any arrangement of three of these nucleotides. Each triplet of nucleotides codes for one amino acid. First transcription will begin in the nucleus where mRNA will transcribe the DNA template. During both transcription and translation, there are three steps. The first step in transcription is initiation where RNA polymerase separates a DNA strand and binds RNA nucleotides to the DNA. RNA nucleotides are the same as DNA ones except that U replaces the T. The second is just the elongation of the mRNA. The third step of transcription is termination. This occurs when RNA polymerase reads a codon region and the mRNA separates from the