Biochemistry

1. Biochemistry • Study of chemical reactions that take place in our body everyday • Chemical reactions allow us to remain alive • Rearrangement of chemical bonds to form products from reactants

2. Macromolecules

3. Water • Most abundant molecule in any cell • Acts as a carrier for dissolved molecules across cell membrane • Used in chemical reactions • Cellular respiration, photosynthesis • Lubricant between organs, tissues, and cells

4. What Makes Water so Important? • Remains liquid over wide range of temps • Dissolves most substances important for cellular function • Oxygen, carbon dioxide, glucose, amino acids • Gradual change in temperature when heated or cooled – helps maintain homeostasis • Expands when it becomes solid • Polar – uneven charge

5. What Makes Water so Important?

6. Water • Dipole nature • Two charges that belong to a water molecule • Small positive charge on two hydrogen atoms • Small negative charge on oxygen atom

7. What do you notice about this picture?

8. Macromolecules • Organic compounds • Contain both hydrogen and carbon • Large molecules composed of smaller subunits • Carbohydrates • Proteins • Lipids • Nucleic Acids

9. Carbohydrates (Sugars) • Biomolecule consisting of carbon, oxygen, and hydrogen. • General molecular formula (CnH₂nOn) (C₆H₁₂O₆) • Roles • Energy storage - plants • Structural support in cells and tissues • Hydrophilic • Pentose/Hexose ring structure

10. Monosaccharides • Used as primary energy source for cellular metabolism (making ATP) • 1 sugar unit • Glucose – grape sugar, blood sugar • Fructose – honey, fruit juices

11. Disaccharides • Consist of two monosaccharides • Maltose – used to make beer • Sucrose – simple sugar found in plant sap • Lactose – milk • Used as energy sources and building blocks for larger molecules

12. Polysaccharides • Complex carbohydrate/polymer • Chain of hundreds to thousands of monosaccharides (monomers) with many subunits • Unbranched – side chains • Branched – single chain

13. Examples • Amylose – soluble component of starch • Glycogen – energy storage in animals • Cellulose – main component of plant cell walls • Chitin – hard exoskeleton of insect and crustaceans

14. Lipids • Non-polar • Made up of mostly carbon and hydrogen • Do not dissolve in water • Roles • Formation of cell membranes • Energy source • Hormones • Vitamins

15. Fatty Acids • Derivative of most lipids (structural backbone) • Consists of • glycerol (alcohol) • 3 molecules of fatty acids • As chain length increases, insolubility in water increases

16. Fatty Acids • Saturated • Max number of hydrogen atoms attached to carbons • Single bonds throughout the carbon chain • Unsaturated • Formation of double bonds in carbon chain • Monounsaturated – one double bond • Polyunsaturated – many double bonds • Causes a bent formation in molecule

17. Cholesterol • Formed in the liver • Structural component of plasma membrane • Function • Maintain membranes • proper membrane permeability/fluidity • Types • LDL – low density lipoprotein • Promote cardiovascular disease • HDL – high density lipoprotein • Good cholesterol – removes cholesterol from artery

18. Proteins • Each cell contains several hundred to several thousand proteins • Composed of many amino acids linked together by a peptide bond that form a polypeptide chain

19. Proteins • Structural – framework support (Eg; hair, tendon, ligaments) • Defensive – infection fighters (Eg; antibodies) • Signal – messenger (Eg; hormones) • Carrier – transport of materials (Eg; hemoglobin) • Recognition and Receptor – cellular markers (Eg; major histocompatability complex) • Enzyme – catalyst (Eg; amylase) • Motile – movement (Eg; actin and myosin)

20. Amino Acids • 20 different amino acids • 8 essential - supplied by diet • Contain: • Central carbon • Amino group (-NH₂) • Carboxyl group (-COOH) • R group • R groups give each amino acids specific characteristics • Polarity, acidity

21. Amino Acids

22. Protein Structure • Primary Structure 1⁰ • Linear sequence of amino acids in polypeptide chain • Changing one amino acid with change overall structure of protein

23. Protein Structure • Secondary Structure 2⁰ • Polypeptides fold or coil into patterns • Result of hydrogen bonding • β-pleated sheets • Side-by-side alignment • (Eg; strength of silk) • α-helix • Coil that is held together by hydrogen bonds between every 4th amino acid • (Eg; transmembraneproteins)

24. Protein Structure • Tertiary Structure 3⁰ • 3-D shape of a protein • Caused by folding

25. Protein Structure • Quaternary Structure 4⁰ • Composed of 2 or more polypeptides • Functional proteins

26. Protein Denaturation • When a protein loses its 3-D structure • Often irreversible • Extreme temperatures • pH • Chemcials

27. Nucleic Acids • Polynucleotide chains serve as assembly instructions for all proteins in living organisms • 2 Types • DNA – deoxyribonucleic acid • Stores hereditary information • RNA – Ribonucleic acid • Hereditary molecule of some viruses • Involved in protein synthesis • Composed of nucleotides • Linked by a phosphodiester bond

28. Nucleotides • Consists of • Nitrogenous base • Uracil (U), thymine (T), cytosine (C), adenine (A), guanine (G) • Sugar • Phosphate groups • Functions • Transport chemical energy • Regulate and adjust cellular activity

29. DNA • Consists of • Deoxyribose sugar • Phosphate group • A, T, C, G • Double stranded molecule (Double Helix) • Two strands of DNA run antiparallel to each other (opposite direction) • 5’ to 3’ • 5’ is the end with the phosphate group • 3’ is where deoxyribose sugar is located • Nitrogenous bases • Held together by hydrogen bonds • A pairs with T ( forms double bond) • C pairs with G (forms a triple bond) • http://i-biology.net/2012/01/15/drew-berrys-animations-of-unseeable-biology-ted-talk/

30. RNA • Consists of • Ribose sugar • Phosphate group • A, U, C, G • Single stranded molecule • Converts information stored in DNA into proteins