1. Protein Synthesis
Genetics

2. Protein Synthesis First step is transcription
The gene’s DNA sequence is copied into a sequence of mRNA.
This creates mRNA
mRNA can leave the nucleus and travel to the site of protein synthesis; DNA cannot
mRNA carries the DNA code to the ribosome

3. Protein Synthesis

4. What is RNA? Another nucleic acid Made of nucleotides
The sugar is ribose; the phosphate is the same; 3 of the 4 bases are the same
Uracil replaces thymine
It is single stranded

5. What is RNA?

6. Transcription
A single strand of RNA is made from one strand of the DNA
The DNA strand being transcribed is called the coding or template strand; the other side is the non-coding or anti-sense strand

7. Transcription
Transcriptions starts at a promoter. This is the base sequence of DNA that signals the start of a gene
RNA polymerase begins transcription at the promoter region
Transcription has three stages: initiation, elongation, and termination

8. Transcription

9. Transcription

10. Types of RNA
Messenger RNA (mRNA) carries DNA code for making a protein
Ribosomal RNA (rRNA) is part of the ribosome structure
Transfer RNA (tRNA) bind to the mRNA and to amino acids

11. Protein Synthesis
After mRNA is formed, it is processed, spliced, and edited
Segments made from introns are cut out; segments made from exons are left in
Introns are intervening sections of DNA that do not code for anything; Exons are expressed sequences

13. Protein Synthesis Three DNA bases specify one amino acid
Three RNA bases specify one amino acid
A chain of amino acids is a protein

14. Protein Synthesis
Once the mRNA carries the code to the ribosome, the protein can be assembled.
The assembly step is called translation
This involves tRNA

15. Protein Synthesis
Each tRNA has three anticodons (bases) attached to one end.
These bases match up with bases on the mRNA
If they fit, that amino acid is added to the chain

17. Translation

18. Translation

19. Translation

20. Translation

21. Translation
Also has three stages: initiation, elongation, and termination. In translation, these stages refer to the assembling and lengthening of the protein chain;
In transcription, these stages refer to the making and lengthening of the mRNA strand

22. Translation

23. Proteins