Module #1 pages 14 – 17

Protein synthesis – the process by which cells make proteins

Protein synthesis occurs in two steps

Step #1 transcription

Step #2 is translation

Step 1. Transcription

Takes place in the nucleus of the cell

DNA unwinds

mRNA is synthesized (made)

mRNA is a single strand vs. DNA which is a double strand of nucleic acid

In mRNA thymine is replaced by uracil in the mRNA

http://www.lba.cnptia.embrapa.br/Bioinf/gui/content/tools/fasta/transcription.gif

Transcription

Step #2: TranslationmRNA leaves the nucleus and enters the cytoplasmmRNA joins with a ribosome

Codons are translated into particular amino acids

Amino acids are carried by transfer RNA to the site of the ribosome where the anticodon of the tRNA and codon of the mRNA bond

Two amino acids then are forced to line up beside one another and a chemical process involving enzymes link the amino acids together two at a time by forming a peptide bond

This happens over and over again until a large protein is formed

http://users.rcn.com/jkimball.ma.ultranet/BiologyPages/T/Translation.gif