Proteins And Its Effect On Human Body

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Proteins are one of the most important biological molecules in the body; they make up more than 50% of the dry mass in human body cells. Their simple structure can be described as amino acid polymers as they are made up of many amino acid monomers stringed together in a linear fashion, which then gives rise to more complex structures, as various bonding and manipulation takes place. The name ‘protein’ comes from the Greek word meaning ‘holding first place’ which supports the fact that they are essential to life. Proteins, depending on their structure and where they are found, play very different roles in an organism. One of the main types of proteins are enzymes which act as biological catalysts, and are fundamental to the chemical…show more content…
An amino acid is made up of a carbon atom in the centre (known as the  carbon), a carboxyl group, amino group, a hydrogen atom and an R group (figure 1). The R group is the section of the amino acid that determines its chemical properties. In glycine, the R group is hydrogen. Some of the amino acids have R groups that are hydrophobic and some have R groups that are hydrophilic and this often determines how the protein folds into its tertiary structure and also where they can be found within the cell. It is the sequence of these amino acids that determines the type of protein that is made. Amino acids join to form proteins in a process known as protein synthesis where a gene is expressed to produce a polypeptide chain. After the genetic code has been translated from the DNA in the nucleus, the resulting mRNA is transcribed into a polypeptide in the cytoplasm of the cell. The mRNA binds to a ribosome and has 3 base pairs exposed called a codon. The anticodon of a tRNA molecule can then bind to the codon as it has complementary base pairs, and it carries with it an amino acid. The first amino acid in the chain is always methionine. When a second tRNA, carrying a different amino acid arrives and binds, a peptide bond forms between the two amino acids and the resulting product is a dipeptide molecule – two amino acids joined together. This process continues and as more amino acids are joined together by peptide
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