2. TRANSCRIPTION TRANSLATION IB BIOLOGY TOPICS 4, 5

4. TRANSCRIPTION OVERVIEW 1. Initiation RNA polymeraseII RNA polymeraseII TATA box TATA box 2.Elongation addition of RNA nucleotides 5`  3` direction 5`  3` direction

5. 3.Termination AAUAA AAUAA prokaryotes vs. eukaryotes

6. Prokaryotic Transcription

7. Eukaryotic Transcription

8. 4 types of RNA  MESSENGER (mRNA) Single stranded Template for aa sequencing during translation Codon: 3 consecutive bases coding for a specific aa for a specific aa (64 possible codons for 20 aa) (64 possible codons for 20 aa)

9.  Transfer (tRNA) Sequence of anticodons Link with aa and transfer them to mRNA transcript

10.  Ribosomal (rRNA) building blocks of ribosomes  Small nuclear RNA (snRNA) utilized in eukaryotic mRNA processing

13. TRANSLATION OVERVIEW http://www.stolaf.edu/people/giannini/biological%20anamations.html

14. Translation  The process of forming peptide bonds between amino acids in a sequence defined by mRNA is called translation.  Involves:  (i) charging of the tRNA with the specific amino acids and  (ii) synthesis of polypeptide chain by the ribosomes.

15. tRNA

16. Anticodon  The middle loop that sticks out from the opposite end of the tRNA contains a triplet of bases complementary to the bases of the mRNA. This triplet is referred to as an anticodon.  The middle loop that sticks out from the opposite end of the tRNA contains a triplet of bases complementary to the bases of the mRNA. This triplet is referred to as an anticodon.

18. Ribosomes page 63  Ribosomes are huge nucleic acid-protein complexes, each made of two subunits (small and large) that come together only during protein synthesis. Otherwise they float separately in the cytoplasm.

21. The Translation Process  Translation consists of: – initiation – elongation – termination  Ribosome moves along the mRNA towards the 3’ end. The start codon is nearer to the 5’ end than the stop codon.  Animations Animations

22. An overview of the subject  Transcription and Translation Transcription and Translation Transcription and Translation  Translation; the Sequence Translation; the Sequence Translation; the Sequence  http://carbon.cudenver.edu/~bstith/transla.M OV http://carbon.cudenver.edu/~bstith/transla.M OV http://carbon.cudenver.edu/~bstith/transla.M OV

23.  Look over the gene expression in eukaryotes page 61.  Regulation of transcription Animations AnimationsAnimations Lac operon The lac Operon The lac OperonThe lac Operon Tryp operon Tutorial 13.2 The tryp Operon Tutorial 13.2 The tryp OperonTutorial 13.2 The tryp Operon