1. 6D Gene expression the process by which the heritable information in a gene, the sequence of DNA base pairs, is made into a functional gene product, such as protein or RNA

2. http://www.youtube.com/watch?v=OEWOZS_ JTgk http://www.youtube.com/watch?v=OEWOZS_ JTgk

3. Gene expression Controls & regulates protein synthesis (transcription & translation) Remember, every cell is your body contains the exact same DNA…

4. …so why does a muscle cell have different function and structure than a nerve cell?

5. Because some genes are expressed in a muscle cell that are not expressed in a nerve cell and vice versa. Different genes can also be expressed in response to environmental factors or during different stages of an organism’s life cycle.

6. Gene expression Its like a light switch… certain traits are “turned on” & “turned off”

8. Gene Segment of DNA that codes for a trait Ex: hair color, eye color

9. Intron any nucleotide sequence within a gene that is removed by RNA splicing while the final mature RNA product of a gene is being generated

10. Exon nucleotide sequence encoded by a gene that remains present within the final mature RNA product of that gene after introns have been removed by RNA splicing. This is the expressed genetic material… the light is turned on.

12. Gene Expression in Prokaryotic Cells Prokaryotic cells such as… BACTERIA … contain operons.

13. Operon Groups of genes that are regulated together. “Buddy system” Located next to 2 regulatory regions of DNA – promoter and operator

14. Promoter a region of DNA that initiates transcription of a particular gene promoters are located near the genes they transcribe

15. Operator a gene that activates the production of messenger RNA by adjacent structural genes

16. When RNA polymerase binds to the promoter, it is a signal that shows RNA polymerase where to begin transcription. The operator is adjacent to the promoter and it controls the rate of transcription.

17. Repressor A protein called a repressor can bind to the operator. If the repressor binds to the operator, the RNA polymerase cannot access the operon and transcription does not occur.

19. lac operon

20. The group do 3 genes (lac Z, lac Y, lacA) MUST be turned on before the bacterium can use lactose as food. When lactose is not present in the bacterium’s environment, the repressor binds to the operator. The protein blocks the movement of RNA polymerase along the DNA, and the operon is not transcribed into RNA.

21. When lactose is present, the repressor binds to lactose instead opt to the operator. The path of DNA is cleared from transcription to occur (like a gate across a road).

23. Gene Expression in Eukaryotic Cells

24. Genes are rarely found in clusters that are activated by the same promoter. Many eukaryotic genes are preceded by a short region of DNA called the TATA box. Gene Expression in Eukaryotic Cells

25. TATA box Positions RNA polymerase.

26. Transcription Factors DNA-binding proteins that aid in regulating gene expression. Many types of transcription factors. Each type affects gene expression in different ways. Ex: opening tightly packed chromatin (enhancing transcription)

27. Types of Transcription Factors opening tightly packed chromatin (enhancing transcription) Attracting RNA polymerase Blocking access to certain genes

30. http://www.youtube.com/watch?v=T9Wszg7F hxE http://www.youtube.com/watch?v=T9Wszg7F hxE http://www.youtube.com/watch?v=2sMFswbO gKk

31. http://phet.colorado.edu/en/simulation/gene- expression-basics

32. http://phet.colorado.edu/en/simulation/gene- machine-lac-operon