Protein Synthesis

 

Protein Synthesis video^

 

    Protein Synthesis has two main steps and they are transcription and translation. Transcription is where it makes a copy of one gene in DNA into mRNA. Translation takes the mRNA and translates it into a protein. We will take a closer look into these steps.
  TRANSRIPTION: 1. The enzyme helicase unwinds and unzips one gene of the DNA. 2. Complementary RNA base pairing attaches to form a mRNA 3. The enzyme RNA polymerase forms a sugar phosphate backbone and checks for mistakes. 4. The mRNA detaches and leaves the nucleus through the nuclear pores and the DNA winds back up.
TRANSLATION: 5. mRNA moves to join a ribosome in the cytoplasm 6. Initiation (the first codon on any mRNA molecule is called the initiator) 7. Elongation: ribosomes job is to position the tRNA with its corresponding amino acid onto the matching mRNA molecule. Then the amino acids bond together with a peptide bond and with the help of the enzyme peptidyl transferase. 8. Termination: the last codon on any mRNA chain. The last codon is the stop codon and it does not have a matching amino acid so that is the message to stop. The amino acid chain then detaches and is considered a protein.

 

      Below is the way that the sequence of DNA is transformed to mRNA and then to tRNA and then to amino acids. From DNA to mRNA they just pair up with their complementary base pairing and since it is turning into an RNA strand there is no Thymine, in its replace there is Uracil. From the mRNA to tRNA they do the came thing find their complementary base pairs. A short cut to this is just to look back at the DNA strand and change all the Thymine's to Uracil's. To find the matching amino acids to the tRNA you look at the mRNA strand and find them on the mRNA codon chart.

 

 

 MUTAGENS

    Some environmental mutagens are UV rays, gamma rays, ionizing radiation, caffeine, aflatoxin (from mold) and ISD. There are two types of mutations that can come from these mutations they are gene mutation or chromosome mutation. A gene mutation is the change of one or more nucleotides in a single gene. This affects the outcome of the protein and might affect the job that the protein does. A chromosome mutation is a mutation of all or part of a chromosome, which affect many genes. A chunk of the chromosome may be missing/or added. This affect many genes which will also affect the proteins being made. When a protein is made it is made to do a specific job, so when the protein gets messed up the job also gets messed up causing abnormalities. For example, extra limbs, downs syndrome or even making a person have male and female parts.

    A genetic disorder is an illness caused by one or more abnormalities in the genome, especially a condition that is present from birth. Two examples of these are Klinefelter syndrome and Turners Syndrome. Klinefelter syndrome is when there is an extra sex chromosome. For example, a persons sex chromosomes are XXY instead of XX or XY. This causes the person to have both female parts and male parts (breasts and testies). If one has this syndrome their IQ is usually impaired.  In the Turners syndrome the person is missing a sex chromosome. So their sex chromosome is usually just X. This causes women to be short and have a fold in the neck when they are young and they cannot have babies. Also, their breasts don't develop properly.