1. Protein Synthesis
AP Ch 17

2. Unit Review Unit 5: Cellular Biology Unit 6A: Cellular Biology
Cells Reproduce (mitosis, meiosis, binary fission)
Unit 6A: Cellular Biology
DNA (structures and functions)
Unit 6B: Cellular Biology
Gene expression (DNA provides instruction for protein biosynthesis)
Unit 6C: Genetics
The logical conclusion of unit 5 & 6:
DNA is passed from parent to offspring b/c meiosis
Genes within the DNA are used to build proteins
Protein traits are a macroscopic visual to inheritance!

3. Vocab Review Protein: Protein Synthesis: Gene Expression:
Carbon-based molecules that build living organisms
Protein Synthesis:
Process in which cells construct protein macromolecules
Gene Expression:
Sections of DNA provide instructions to build protein biosynthesis

4. Molecule Review

5. Protein Synthesis Overview
DNA contains the chemical code for life
mRNA copies DNA (Transcription)
mRNA edits the code (RNA processing)
tRNA decodes mRNA (Translation)
Amino acids are linked to form protein

6. Part I: Transcription

7. Transcription
DNA contains the instructions for making protein (nucleus)
Proteins (T.f.) attach to DNA at a promoter region
RNA polymerase attaches to proteins and uses one strand of DNA as a template and reads 3’  5’

8. Transcription
Complimentary RNA nucleotides are assembled into RNA transcript.
RNA transcript separates from DNA at a terminating sequence*

9. Transcription Animation

10. Part II: RNA processing

11. RNA processing A U G A U A G C G C A U
Only fragments of a gene make a protein
mRNA is edited before leaving the nucleus
A U G A U A G C G C A U 5’ 3’

12. RNA processing Exon Intron Exon A U G A U A G C G C A U
mRNA is made up of introns and exons
Introns: noncoding DNA
Exons: expressed DNA
Exon
Intron
Exon
A U G A U A G C G C A U 5’ 3’

13. RNA processing Spliceosome A U G A U A G C G C A U
Enzymes remove intron & connect exons
Spliceosome
A U G A U A G C G C A U 5’ 3’

14. GTP A A A A A A RNA processing A U G G C G C A U
Enzymes remove intron & connect exons
Enzymes attach 5’ GTP cap & poly-A tail
mRNA leaves through nuclear pores
GTP
A A A A A A
A U G G C G C A U 5’ 3’

15. RNA processing animation

16. Part III: Translation

17. Before we begin… There are 22 amino acids on Planet Earth
Every tRNA attaches to one amino acid

18. Translation
mRNA travels through the cytoplasm to the ribosome

19. Translation tRNA brings amino acid based upon mRNA codon
Amino acids are linked through peptide bonds
tRNA continues to bring amino acids until a stop codon is reached
Polypeptide chain is released & protein is complete

20. Translation Animations

21. mRNA, tRNA, & Amino acids
mRNA codon is used with a decoder chart to determine the correct amino acid associated with tRNA

22. Codon Chart CODON = AUG A U G Amino acid is methionine
Try finding the amino acid for the codon ‘CUA’
LEUCINE

23. Gene Expression