1. Aim: How are proteins synthesized? What are the main jobs of DNA? Replication & Protein Synthesis

2. What are the building blocks of Nucleic Acids? Nucleotides!!

3. What are the two major types of Nucleic Acids? DNA and RNA 3

4. RNA vs DNA nucleic acids Single stranded Sugar –Ribose Bases: (A, U, G, C) Adenine – Uracil Guanine – Cytosine 2 types – mRNA and tRNA Double stranded Sugar – Deoxyribose Bases: (A, T, G, C) Adenine – Thymine Guanine – Cytosine 1 type – main instructions

5. What is the connection between DNA, RNA, and Protein Synthesis? Every gene in the DNA has the instructions to synthesize a single protein RNA transports the instructions in the cell 5

6. What are the two major steps involved in protein synthesis? Transcription Translation

7. Transcription Nucleus The DNA sequence for one gene is “copied” and used to produce a mRNA (messenger) molecule The mRNA strand is complementary to the DNA

8. What is the importance of mRNA in protein synthesis? DNA is too large and important to leave the nucleus. mRNA will take DNA’s instructions to the cytoplasm 8

9. Why does mRNA have to leave the nucleus? mRNA Because the cytoplasm contains the sites of protein synthesis (ribosomes) and the free amino acids which make up the proteins.

10. Is transcription the same as replication? Transcription – coded copy of a segment of DNA to be used to make proteins. Replication - an identical copy of the entire DNA to be given to new cells

11. Ribosomes are in the cytoplasm Ribosomes are the site of protein synthesis

12. Translation: Ribosome! mRNA molecule directs the assembly of a chain of specific amino acids Peptide bonds are formed between amino acids 12

13. How is the mRNA capable of providing instructions to make a protein? in the form of CODONS: a series of 3 adjacent bases codes for a specific amino acid 13

14. Which two body systems provide the cells with the amino acids needed for protein synthesis? Digestive and Circulatory Systems!!! 14

15. What transports the amino acids to the ribosomes? tRNA

17. How does tRNA know what amino acid to deliver? mRNA - tRNA GGG…… AUC…… ACC…… CGU…… CCC UAG UGG GCA The anti-codon on the tRNA matches up with the correct mRNA codon and releases its amino acid so it can join the growing protein (polypeptide) chain. tRNA Anticodon mRNA codon

18. mRNA - tRNA – amino acid GGG……CCC AUC……UAG ACC……UGG CGU……GCA

19. When does protein synthesis stop? When the ribosome reaches one of three “stop codons” Stop Codons: UGA, UAA, UAG

20. mRNA vs. tRNA Transfer RNA Carries copy of instructions from nucleus to ribosome Carries amino acids to the ribosome Messenger RNA

21. 1. mRNA enters the cytoplasm. 2. tRNA picks up amino acids and carries them to the ribosome and the mRNA. 3. The anti-codon on the tRNA matches up with the mRNA codon. Steps of Protein Synthesis: 4. Peptide bonds are formed between adjacent amino acids. Start Codon: AUG (met)

22. Polypeptide synthesis MOVIE