Protein Synthesis Involves Transcription & Translation
- The 2 steps of protein synthesis:
Process |
Where |
Major Components |
Notes |
Transcription |
In the nucleus |
DNA gene
RNA polymerase |
Gene is activated.
A copy of the code is made from RNA (m-RNA)
m-RNA leaves the nucleus, goes to cytoplasm. |
Translation |
In the cytoplasm, on the ribosomes |
m-RNA
Ribosomes
Peptidyl transferase enzyme
Transfer RNAs |
Ribosome decodes the m-RNA and makes the correct protein. |
- Keeping the main copy of the genes in the nucleus protects it from damage
- There are many DNA repair mechanisms in the nucleus
Information is Stored in the Code Letters of DNA
- All hereditary information is stored in genes, which are parts of giant DNA molecules
- Genes code for the amino acids of proteins
- DNA is the archival copy of the code- kept in nucleus where it is protected & repaired
- DNA is organized with special proteins into chromosomes
- For protein synthesis a working copy of the code is made from RNA
- Overall scheme: DNA -> RNA -> protein
- Another version: “One gene, one enzyme”
The Code is Based Upon the Structure of DNA
Information is Stored in the Code Letters of DNA
- All hereditary information is stored in genes, which are parts of giant DNA molecules
- Genes code for the amino acids of proteins
- DNA is the archival copy of the code- kept in nucleus where it is protected & repaired
- DNA is organized with special proteins into chromosomes
- For protein synthesis a working copy of the code is made from RNA
- Overall scheme: DNA -> RNA -> protein
- Another version: “One gene, one enzyme”