1. Protein Synthesis

2. Steps: TRANSCRIPTION DNA unwinds, RNA is made from DNA DNA acts as a template for RNA

3. Protein Synthesis mRNA It is copied from the part of DNA called a gene. mRNA for hair color mRNA for liver enzymes mRNA for skin color Read 3 bases at a time (codon)

4. Protein Synthesis mRNA copy moves out of nucleus into cytoplasm. Transcription

5. Protein Synthesis tRNA becomes active when amino acids are attached to them. They carry amino acids to the ribosome. They have the anticodon.

7. Protein Synthesis mRNA attaches to the ribosome in cytoplasm.

8. A tRNA bonds complementarily with the mRNA by its anticodon.

9. Translation A second tRNA bonds with the next codon on the mRNA, the amino acid joins onto the amino acid of the first tRNA making a peptide bond. **peptide bond is a fancy name for a covalent bond. Translation

10. A third tRNA, with the correct anticodon, brings a third amino acid to the mRNA. Protein Synthesis Protein Synthesis

11. The ribosome moves along. The first tRNA leaves the ribosome.

12.  All the rest of the amino acids are added. The ribosome moves down the mRNA and complimentary tRNA drops off the appropriate amino acid. Protein Synthesis Protein Synthesis

13. Eventually a stop codon is reached on the mRNA. There is no anticodon for a stop codon The newly synthesised polypeptide leaves the ribosome.

14.  The mRNA and ribosome come apart. The tRNA, ribosome, and mRNA are all reused to make more of the same type of protein.

15.  For each gene there is one polypeptide synthesized.  So if an organism has 100 genes it has 100 proteins to make

17. Overview

18. Summary