1. Protein Synthesis: A Fairy Tale1

2. The story….
Once upon a time there were two fraternal twin brothers: Donald N. Armstrong and Ronald N. Armstrong. 2

3. Donald
Donald was the smarter of the two, and he was a successful inventor with many patents. 3

4. Ronald
Although Ronald was not as smart as his brother, he was extremely loyal. 4

5. An idea…
One day Donald came up with an idea for a solar powered car 5

6. Sign of the Times….
Given the ever-present possibility of energy shortage, an efficient solar powered car would be in great demand. 6

7. Back at home…
However, Donald really didn't want to leave his comfortable estate. 7

8. How to send the idea….
He certainly couldn't take a chance by using or a fax to send his plans to the factory. They might be stolen by industrial spies! 8

9. Ronald, the loyal messenger…
Donald knows his loyal brother would do anything for him, so he asks him to be a messenger and carry the plans to the factory. 9

10. At the factory….
At the factory, the assembly line is set up and factory workers bring the parts to assemble the prototype. 10

11. Success!
The car proves to be enormously successful. 11

12. The End of the Fairy Tale….
The Armstrong brothers buy an even bigger estate and live happily ever after!" 12

13. DNA

14. DNA and RNA DNA - Double stranded Contains deoxyribose (5 carbon sugar
Bases: A,G,C,T
RNA
- Single strand of nucleotides
Contains ribose
Bases: A,G, C, U

15. DNA and RNA In RNA, uracil is complementary to adenine
DNA: A C T G G T A C
mRNA: U G A C C A U C

16. From Gene To Protein DNA contains the code to make a protein
TRANSCRIPTION: The DNA is transcribed (rewritten) to mRNA
TRANSLATION: The mRNA is translated into a protein

17. The Genetic Code
The RNA made during transcription is called Messenger RNA, abbreviated mRNA

18. Transcription Makes a single stranded mRNA from a DNA template
Occurs in the nucleus

19. Transcription
STEP 1: The enzyme RNA polymerase binds to a promoter sequence on the gene- a specific sequence that acts as a “start signal” for transcription
Example) TATA box

20. Transcription
STEP 2: DNA helicase, an enzyme, unwinds the double stranded DNA, exposing DNA nucleotides on each strand

21. Transcription
STEP 3: RNA polymerase adds complementary RNA nucleotides as it “reads” the gene.
Eventually, it reaches a “stop” signal, a sequence of bases that marks the end of the gene.

22. DNA  RNA

23. Transcription

24. Let’s Review! What occurs during transcription?
Where in the cell does this occur?
What type of RNA is made?