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Protein Synthesis The Expression of a Gene   Ã‚  Ã‚  Ã‚  Ã‚  The process of Protein Synthesis involves many parts of the cell. Unlike other similar productions, this process is very complex and precise and therefore must be done in proper sequence to work effectively. The slightest error during this process could cause the action to experience difficulty or even fail. For example, in the production of starch, glucose molecules are combined to be stored and eventually utilized as usable chemical energy. The cell can break down the starch with little difficulty as if each molecule was identical, even though there is a wide variety of molecules. This is a different case in Protein Synthesis. In Protein Synthesis, there are twenty different amino acids and if one is out of place than is will effect the specificity of the protein. In a healthy person, the protein hemoglobin can be found in red blood cells, hemoglobin is helps with the transfer of respiratory gases from the blood to the tissues of the body. With an illness called sickle-cell anemia, the red blood cells are changed from a round, disk shape to a floppy looking sickle shape. These cells therefore cannot pass through small blood vessels due to their divergent shape. The actual cause of this mutation is a gene disorder, where the sixth codon of the protein glutamaric acid is changed with valine. This small change in the genetic code can cause severe defects in the effected such as blood clots, severe disorders and even death. All this can result from a misinterpretation in one codon in a chain of hundreds! Protein synthesis acts in this way, that is if there is only the most minuscule mistake it can have monstrous effects. THE BASICS OF DNA AND GENES   Ã‚  Ã‚  Ã‚  Ã‚     Ã‚  Ã‚  Ã‚  Ã‚  Protein synthesis first begins in a gene. A gene is a section of chromosome compound of deoxyribonucleic acid or DNA. Each DNA strand is composed of phosphate, the five-carbon sugar deoxyribose and nitrogenous bases or nucleotides. There are four types of nitrogenous bases in DNA. They are (A)denine, (G)uanine, (T)hymine, (C)ytosine and they must be paired very specifically. Only Adenine with Thymine (A-T) and Guanine with Cytosine (G-C).   Ã‚  Ã‚  Ã‚  Ã‚  To form a polynucleotide DNA, many nucleotides are linked together with 3`-5` phosphodiester linkages. In a compl... ... structure of many chromosomes ( chromosomal mutations). Mutations are not always bad because they can cause adaptation and variation in people. Point Mutations and Base Pair Mutations   Ã‚  Ã‚  Ã‚  Ã‚  The most common type of mutation involves a change in only a single base pair. This change only effects a single codon of the gene. There are three types of base pair mutations: silent, missense, and chain termination. Silent mutations involves the repositioning of the third codon. This does not effect the amino acid sequence. Missense mutation is where one codon is altered to code for a different amino acid (sickle cell anemia). Chain termination mutations involve the codon being changes to a stop codon. This causes the protein synthesis to remain incomplete and lose most of the biological activity. Frame shift Mutations and Mutagens   Ã‚  Ã‚  Ã‚  Ã‚  This is the addition or deletion of one or more base pair but not multiples of three. This causes the ribosome to read the codon incorrectly causing and entirely different amino acid sequence. Mutagens are agents that increase the frequency of mutations. X-rays or other radiation are causes of mutagens.