1. Title of notes: Transcription and Translation p. 16 & 17

2. Title within the notes:Transcription

3. I can describe the process used in the creation of a protein.
Learning target
I can describe the process used in the creation of a protein.
Today I am…
Actively engaged in lecture of transcription and translation.
So that I’ll be able to…
understand how important protein synthesis is to life.
I’ll know I’ve got it when…
Complete all notes and homework.

4. Pathway to Making a Protein
DNA
mRNA
tRNA (ribosomes)
Protein

5. Protein Synthesis
The production or synthesis of polypeptide chains (proteins)
Two phases: Transcription & Translation
mRNA must be processed before it leaves the nucleus of eukaryotic cells

6. DNA  RNA  Protein Eukaryotic Cell DNA Pre-mRNA mRNA Ribosome Protein
Nuclear
membrane
Transcription
RNA Processing
Translation
DNA
Pre-mRNA
mRNA
Ribosome
Protein
Eukaryotic Cell

7. Transcription
The process of copying the sequence of one strand of DNA, the template strand
mRNA copies the template strand
Requires the enzyme RNA Polymerase

8. Template Strand

9. Transcription
During transcription, RNA polymerase binds to DNA and separates the DNA strands
RNA Polymerase then uses one strand of DNA as a template to assemble nucleotides into RNA

10. Transcription
Promoters are regions on DNA that show where RNA Polymerase must bind to begin the Transcription of RNA
Called the TATA box
Specific base sequences act as signals to stop
Called the termination signal

11. RNA Polymerase

12. mRNA Processing
After the DNA is transcribed into RNA, editing must be done to the nucleotide chain to make the RNA functional
Introns, non-functional segments of DNA are snipped out of the chain

13. mRNA Editing
Exons, segments of DNA that code for proteins, are then rejoined by the enzyme ligase
A guanine triphosphate cap is added to the 5” end of the newly copied mRNA
A poly A tail is added to the 3’ end of the RNA
The newly processed mRNA can then leave the nucleus

14. Result of Transcription
New Transcript
Tail
CAP

15. mRNA Transcript
mRNA leaves the nucleus through its pores and goes to the ribosomes

16. Title within the notes:Translation

17. Translation
Translation is the process of decoding the mRNA into a polypeptide chain
Ribosomes read mRNA three bases or 1 codon at a time and construct the proteins

18. Transcription Translation
Transcription occurs when DNA acts as a template for mRNA synthesis. Translation occurs when the sequence of the mRNA codons determines the sequence of amino acids in a protein.
Translation

19. Ribosomes Made of a large and small subunit
Composed of rRNA (40%) and proteins (60%)
Have two sites for tRNA attachment --- P and A

20. Step 1
mRNA transcript start codon AUG attaches to the small ribosomal subunit
The exposed codon attracts a complementary tRNA
The tRNA (anticodon) pairs with the mRNA (codon).

21. Step 2 Peptide bonds join the amino acids
Bond is broken between tRNA and its amino acid.

22. Step 3 The ribosome pulls the mRNA strand the length of one codon.
The tRNA is then shifted into the exit site and released
The next mRNA (codon) is exposed.

23. End Product –The Protein!
The end products of protein synthesis is a primary structure of a protein
A sequence of amino acid bonded together by peptide bonds
aa1
aa2
aa3
aa4
aa5
aa200
aa199

24. Reading Transcription Pages 229 -232 Translation Pages 233 -237
Write down two facts from transcription and bullet point facts
Write down two facts from translation and bullet point facts

25. 3 steps of translation
Create a foldable with the 3 steps of translation.
Create a drawing for each step
Short description of what occurs during the step