Foundation of Molecular Biology

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.

3) As a ribosome moves along the mRNA, the genetic message is translated into a protein with a specific amino acid sequence.

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).

(PCR), which isolates small fragments of DNA that have a high degree of variability from

2. The millions of copies that are created from a meager amount of DNA assist the laboratory in generating a DNA profile that will be compared against the DNA profile of the suspect.

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.

What does the PCR do? PCR is a method by which fragments of DNA can be duplicated. This makes PCR more sufficient amongst other Felds in forensic science.

It is used to amplify a sample of DNA, creating thousands or even millions of copies of a certain sequence of DNA. "The story of modern PCR begins in 1976 with the isolation of Taq polymerase from the thermophilic bacterium Thermus aquaticus" (https://www.thermofisher.com/uk/en/home/brands/thermo-scientific/molecular-biology/molecular-biology-learning-center/molecular-biology-resource-library/spotlight-articles/history-pcr.html).

Translation is the final step on the way from the DNA to a protein. It is the synthesis of which proteins are directed by mRNA template. The information contained within the nucleotide sequence of the mRNA is read as three letter word, called codons. Each word stands for just one amino acid. During translation of the amino acids, they are linked together to form the polypeptide chain in which will later folded into the protein. The translation is also dependent on many components, of which the two are extra important. To start off the ribosome which is the cellular factory responsible for a protein synthesis. It is made up of two different subunits, one very small and one very large and is built up from rRNA and a protein. Inside the ribosome the amino acids are linked into a chain through many biochemical reactions. The other component is the tRNA, a specialized RNA

PCR is a tool used by those looking to amplify small amounts of DNA for identification purposes. Thermus Aquaticus’ main use is within this DNA amplification process (PCR) is its reproduction enzyme. The bacterium’s polymerase, called taq polymerase (name after the bacterium), is used to reproduce

*translation essentially is the conversion of a sequence of genetic bases on messenger RNA into an amino acid. 7. The protein becomes folded as it leaves the ribosome. This allows the protein to carry out a particular function.

Translation is the modification of language of a mRNA molecule from a nucleotide base sequence to an amino acid sequence. There are three main steps in translation which are: initiation, elongation, and termination. In order for translation to begin, initiation must occur. Initiation begins at the codon AUG, but in order to know which AUG to begin at, the Shine-Dalgarmo sequence is the indicator of where to begin. The Shine-Dalgarmo sequence is made up of a few purine nucleotides strung together,

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.

Protein synthesis is one of the most fundamental biological processes. To start off, a protein is made in a ribosome. There are many cellular mechanisms involved with protein synthesis. Before the process of protein synthesis can be described, a person must know what proteins are made out of. There are four basic levels of protein organization. The first is primary structure, followed by secondary structure, then tertiary structure, and the last level is quaternary structure. Once someone understands the makeup of a protein, they can then begin to learn how elements can combine and go from genes to protein. There are two main processes that occur during protein synthesis, or peptide formation. One is transcription and

The polymerase chain reaction or PCR for short can be used to create many copies of DNA. This allows the DNA to then be visualized using a dye like ethidium bromide after gel electrophoresis. The process has been refined over the years, however the basic steps are similar.