Protein Synthesis

Protein Synthesis is broken up into two stages: Transcription and Translation. Transcription happens when the DNA is unwinded and unzipped by the enzyme Helicase. Helicase travels up the middle of the DNA and splits the hydrogen bonds that hold the bases together. Next what happens is called complimentary base pairing. This is when one strand of DNA is paired up with its complimentary bases. Once that is done, a new sugar phosphate backbone is created. Finally the DNA will zip itself back up and a new mRNA strand is formed. The next step is Translation. This is when a ribosome attaches to the mRNA strand. The appropriate molecule of tRNA attaches and carries the activated amino acid to the ribosome. Anticodon bases pair with the codons in order to bring the specific amino acid to the correct place. The process repeats itself until the entire message is read and all the amino acids are brought in sequence, forming a polypeptide chain.

mRNA is coded by obtaining the codons for DNA. This is by taking the opposite bases from the sequence of DNA it is being coded by. The Thymine from the DNA is replaced by Uracil in the mRNA sequence. Using the mRNA sequence found, we can then figure out which amino acid goes where.

Mutagens such as X-Rays, Gamma Rays, Ultraviolet Rays, Chemicals and Viruses can all effect protein synthesis in a significant way. They can cause deletion and addition as well as substitution which all negatively effect us. Addition will add an extra base and screw up all of the amino acids after the addition has taken place. The same kind of situation will happen with deletion. After one base is taken out, all of the other amino acids will be incorrect. Substitution is not quite as serious as it will only mess up the one amino acid for the base it replaced. Mutations like these can cause Autism, Downs Syndrome, and other mental illnesses.