1. Unit 8 Lesson 2 Notes

2. Review from Lesson 1 Protein synthesis is the making of protein using information from DNA.

3. Let’s Review You learned the differences between DNA and RNA. You learned tRNA is transfer RNA and it transfers amino acids from the cytoplasm to the ribosomes to form protein chains.

4. A nucleic acid is made up of repeating nucleotides. A nucleotide is a sugar, a phosphate and a base. In RNA the sugar is ribose. http://www.biologyjunction.com/images/nucleotide1.jpg

5. RNA contains the base uracil instead of thymine. Uracil is represented by the letter U which bonds with Adenine (letter A). http://www.biologycorner.com/resources/mRNA-colored.gif

6. RNA is made during transcription. Transcription takes place inside the nucleus of the cell. http://www.phschool.com/science/biology_place/biocoach/images/transcription/euovrvw.gif

7. An analogy for why transcription of DNA must occur: – Encyclopedias must stay in the library just like DNA must stay in the nucleus.

8. Transcription During transcription, DNA is used as a pattern to create RNA. Synthesis means to make… so DNA is used to synthesize, or make, RNA. Transcription occurs in the nucleus of a cell.

9. In transcription the four bases in RNA are U, A, G and C. Remember the base that replaces Thymine in RNA is Uracil. http://leavingbio.net/HEREDITY-ORDINARY%20LEVEL_files/image038.jpg

10. RNA Production In transcription, DNA bases are paired with RNA bases. This new single strand of RNA will be used to create proteins with the same base sequence as the original DNA molecule. DNA  RNA A  U T  A C  G G  C http://biology.unm.edu/ccouncil/Biology_124/Images/transcription.gif

11. The process… DNA – TAC ATC GTA CTA mRNA – AUG UAG CAU GAU DNA – TAC CCG GGC AAA mRNA – AUG GGC CCG UUU Notice in this picture that DNA is on the left. We know this because DNA contains the base Thymine (T). RNA is produced on the right… look for the Uracil (U) which is replacing T in DNA. http://science.halleyhosting.com/sci/ibbio/chem/nucleic/chpt15/transcription.gif

12. Your turn! Now it’s time for you to practice creating proteins by copying DNA to make RNA.