1. Cellular Metabolism Chapter 4

2. Introduction Metabolism is many chemical reactionss Metabolism breaks down nutrients and releases energy= catabolism Metabolism builds molecules to store energy= anabolism

3. Anabolism Eg. Dehydration synthesis

4. Anabolism Peptide bonds link amino acids

5. Catabolism Breaking larger molecules into smaller ones Eg: hydrolysis

6. Enzymes regulate all chemical reactions in cells When a product is made Which product is made How much product is made How quickly the product is made

7. Enzyme Characteristics Catalysts Reactions occur 1,000,000 times faster with enzymes Not part of reaction Not changed or affected by reaction Used over and over Made of protein End in “-ase”

8. Enzyme and Substrate

9. DNA (Deoxyribonucleic acid) Blue prints of enzymes Blueprints of proteins Deciphering genes, chromosomes, DNA. How do they relate?

10. DNA Genetic code This code instructs cells how to synthesize enzymes and protein molecules. Portion of DNA with information for making a particular protein is a GENE All of the DNA in a cell makes up the genome

11. Human Genome 2% of the human genome encodes protein Rest controls when and where genes are used Also many repetitive DNA sequences- we don’t know what for. Completed in 2003

12. DNA replication During cell division, DNA must be copied New cell receives a copy of the DNA Bonds between base pairs of the double strands break

13. Review of Nucleic Acids Contain C, H, O, N, P Function: energy carriers ATP Function: genetic systems DNA, RNA Determine what proteins are made Structure: nucleotides bonded together to form long chains

14. Nitrogen bases RNA – 4 possible Adenine - A Cytosine - C Guanine - G Uracil – U DNA – 4 possible Adenine – A Cytosine – C Guanine – G Thymine - T

15. Base Pairs Nitrogen bases of the nucleotides occur in pairs Hold the 2 strands of DNA together 4 nitrogen bases in DNA Bonding is specific A – T T – A C – G G – C Sequence determines the order of amino acids in a protein

16. DNA Replication DNA separates Each chain links itself to DNA nitrogen bases Forms two new strands of DNA

17. Protein Synthesis HOW TO MAKE A PROTEIN? Need to find the correct order of amino acids to build a protein.

18. Protein Synthesis - Transcription DNA separates Each chain links itself to RNA nitrogen bases (Transcription) 4 nitrogen bases in RNA Bonding is specific A – U U – A C – G G – C Forms a single strand of RNA mRNA tRNA Mutations may occur

19. RNA Messenger RNA- carries the genes’ message out of the nucleus Transfer RNA- correctly aligns amino acids to form proteins

20. Protein Synthesis - Translation RNA “translates” genes’ messages RNA moves out into cytoplasm mRNA binds to a ribosome tRNA binds to specific amino acids Carries them to mRNA Amino acids bond together Form a protein

21. Summary of Replication, Transcription, Translation

22. Metabolism in Cells requires Energy - ATP Aerobic respiration uses oxygen Glucose enters cells Broken into smaller sugar molecules Occurs in cytoplasm Yields 2 ATP These smaller sugar molecules are further metabolized Enter mitochondria Series of chemical reactions yields 34 ATP

23. Aerobic Respiration

24. Metabolism in Body Cells (cont’d) Anaerobic respiration occurs when oxygen is not present Glucose enters cells Broken into smaller sugar molecules in cytoplasm Yields 2 ATP Fats and proteins are also used to make ATP