1. Protein Synthesis Grade 10 EST

2. Recall: DNA DNA is deoxyribonucleic acid Composed of nucleotides Each nucleotide contains – Deoxyribose sugar – Phosphate group (PO 4 -1 ) – Nitrogenous base (A, T, C, or G) Sequence of bases = gene

3. Recall: Proteins A gene is piece of DNA that codes to make a protein. Proteins play specific roles in an organism. – Support (elastin) – Transport (hemoglobin) – Control (hormones, insulin) – Immunity (antibodies) – Catalysis (enzymes)

4. Recall: Protein Structure Protein are made of amino acids. 20 different amino acids Average = 100-200 amino acids in a protein chain

5. Protein Synthesis Protein synthesis is the creation of proteins by cells. Instructions are in genes inside nucleus. Protein synthesis occurs in ribosomes, outside the nucleus.

7. RNA DNA cannot leave the nucleus Messenger between nucleus and ribosome mRNA: messenger ribonucleic acid RNA is single-stranded Thymine (T)  Uracil (U) Ribose sugar

9. Two types of RNA Transfer RNA transfers amino acids from cytoplasm to ribosome (tRNA) Transfer RNA transfers amino acids from cytoplasm to ribosome (tRNA) Messenger RNA acts as a messenger between gene and ribosome (mRNA) Messenger RNA acts as a messenger between gene and ribosome (mRNA)

10. 1. Transcription of DNA into mRNA

11. 2. Attachment of mRNA to Ribosome

12. 3. Translation of mRNA into Protein

13. 4. End of Protein Synthesis UAA, UAG, or UGA nucleotide triplet Chain is complete. Protein is released. Folds into functional shape. Performs its role.

14. Notes Video HW pp. 181-182 due May 22