Biochemistry

1. Biochemistry

2. Matter • Anything that has mass and occupies space • Some matter is changed chemically to produce energy • Energy used to carry out cell activities

3. Properties of Matter • Exists in 3 states • Solid – definite volume, definite shape • Liquid – definite volume, indefinite shape • Gas – indefinite volume, indefinite shape

4. Properties of Matter • Chemical and Physical Properties • Physical Properties – physical appearance or characteristic of a substance • Color • Boiling or Melting Point • Hardness • Chemical Properties – how one kind of matter reacts with other matter • Burning of a substance

5. Properties of Matter • Physical and Chemical Changes • Physical Changes – appearance changes, matter does not • Change of State • Freezing – from liquid to solid • Melting – from solid to liquid • Evaporation – from liquid to gas • Condensation – from gas to liquid • Sublimation – from solid to gas • Change in size – cutting paper • Chemical Change – matter changes • Iron reacts with oxygen to produce rust • Law of Conservation of Matter – matter is neither created nor destroyed, only changes form

6. Atoms and Elements • Atom – tiny unit of matter • Composed of: • Protons - + charge, 1amu, in nucleus • Neutron – no charge, 1amu, in nucleus • Electron - - charge, 0 amu, in electron cloud

7. Atoms and Elements • Element – Substance containing only one type of atom • Atoms of same elements have the same number of protons – called Atomic Number • Hydrogen – 1 proton • Oxygen – 8 protons • Sum of protons + neutrons determines Atomic Mass Number • Isotopes – atoms that have the same number of protons but different numbers of neutrons • Number of electrons = Number of protons; result atom is electrically neutral

8. Atoms and Elements • Elements are arranged according to atomic number in the Periodic Table

9. Atoms and Elements Element Symbols 1st one or two letters of English name Hydrogen - H Helium - He Others from Latin or foreign language names Silver Ag Argenitum (Latin) Tungsten W Wolfran (German) 1st letter always capitalized, 2nd is lower case

10. Atoms and Elements

11. Compounds and Molecules Atoms want to be stable, want a complete outer energy level Combine with other elements; both become stable Compound – substance formed when 2 or more elements bond chemically

12. Compounds and Molecules Stability by sharing or transferring electrons Covalent Bond – electrons are shared Molecule – bonded set of atoms Ionic Bond – electrons are transferred Ion – electrically charged atom Negative Ion – gain electrons Positive Ion – loses electrons Bond forms due to attraction of oppositely charged ions

13. Compounds and Molecules Covalent Bonds – Water (H2O)

14. Compounds and Molecules Ionic Bonds – Sodium Chloride (NaCl)

15. Compounds and Molecules Chemical Formula – Expression of chemical makeup of a compound Shows kinds and number of atoms H2O – 2 atoms hydrogen; 1 atom oxygen Coefficients show number of molecules 2H2O – 2molecules; 4 atoms H; 2 atoms O

16. Mixtures Composed of 2 or more substances that can be separated by physical means Homogeneous – every part looks same Heterogeneous – some sections look different Types Solution Suspension Colloid

17. Mixtures Solution Homogeneous mixture where one substance is dissolved in another Solute – Substance dissolved Solvent – Substance doing the dissolving

18. Mixtures Suspension Heterogeneous mixture of substances larger than molecules or ions Particles may settle Some stay suspended; cloudy appearance Example - Blood

19. Mixtures Colloid Homogeneous mixture with particles larger than in solution but smaller than a suspension Clusters of atoms, ions or molecules Examples – Gelatin, Homogenized Milk

20. Life’s Chemicals Most atoms in Human Body Hydrogen Oxygen Carbon Nitrogen

21. Life’s Chemicals Inorganic Compounds Primarily composed of elements other than Carbon Organic Compounds Contain the element Carbon

22. Water Most abundant inorganic compound in living organisms Composed of Hydrogen and Oxygen

23. Water Universal Solvent – dissolves many substances due to polarity of water Dissolves ionic compounds to produce ions called electrolytes Doesn’t dissolve covalent compounds very well

24. Water

25. Water Dissociates to form H+ and OH- ions Both are equal in distilled water Gives us the pH scale Below 7 – acidic Above 7 – alkaline 7 - neutral

26. Water

27. Water Polarity of water Causes hydrogen bonding – bond between H of one and O of another. Results in water’s unique properties Boiling and Freezing Points Cohesion – attracted to other water molecules – water droplets Adhesion – attracted to other similar molecules – allows movement of water in plants

28. Carbon Dioxide Inorganic even though it contains carbon Source of Carbon and Oxygen in organic compounds by way of photosynthesis

29. Organic Compounds Contain the element Carbon Has 4 electrons in outer energy level Can form 4 bonds – either with other carbons or other elements

30. Organic Compounds Originally believed to have to come from living organisms Many have been synthesized

31. Organic Compounds Often described by structural formulas Show kinds of atoms Show number of atoms Show how atoms are attached to each other

32. Organic Compounds Organic Compound important to Life Carbohydrates Proteins Lipids Nucleic Acids

33. Organic Compounds Processes (reactions) important to organic compounds Dehydration Synthesis Production of a more complex molecule from 2 or more simpler molecules by removing a water molecule Hydrolysis Breakdown of a more complex molecule into simpler molecules by the addition of a molecule of water – usually during digestion

34. Organic Compounds

35. Carbohydrates Composed of Carbon, Hydrogen, and Oxygen Hydrogen: Oxygen ratio always 2 to 1 Used for energy source, structure, and energy storage Classes Monosaccharides Disaccharides Polysaccharides

36. Carbohydrates Monosaccharides – single sugars Most have formula C6H12O6 –different structures Examples – glucose, fructose, galactose Glucose – food product of photosynthesis

37. Carbohydrates

38. Carbohydrates Disaccharides – double sugars Composed of 2 monosaccharides that combine by dehydration synthesis Molecular formula – C12H22O11 Examples Sucrose (Table Sugar) – Glucose + Fructose Lactose (Milk Sugar) – Glucose + Galactose

39. Carbohydrates

40. Carbohydrates Polysaccharides – many sugars Made of many monosaccharides that combine during a series of dehydration syntheses Types Cellulose – structural compound in plants Starch – energy storage in plants Glycogen – energy storage in animal livers; called “animal starch”

41. Carbohydrates

42. Proteins Composed of Carbon, Hydrogen, Oxygen, and Nitrogen; sometimes Sulfur Made up of 20 different Amino Acid joined together by dehydration synthesis reactions. Peptide Bonds join the amino acids – amino group of one amino acid attaches to carboxyl group of another amino acid

43. Proteins Used to build and repair cells; also function as enzymes. Types Dipeptide – 2 amino acids Polypeptide – many amino acids

44. Proteins Amino Acid Structure 3 basic parts around a central Carbon Amino Group – NH2 Carboxyl Group – COOH R-Group – a simple H or group of Carbon and Hydrogen atoms Hydrogen forms the 4th bond.

45. Proteins

46. Proteins Enzyme - protein molecule that acts as an organic catalyst – changes the rate of chemical reaction Acts on a Substrate – Material to be changed Often described as a “Lock and Key” operation Lock – substrate Key - enzyme

47. Proteins

48. Lipids Contain Carbon, Hydrogen, and Oxygen Larger number of Hydrogen atoms and lower number of Oxygen atoms than carbohydrates Insoluble in water Most composed of Fatty Acids Primary function is energy storage but help form cell membranes

49. Lipids Fatty Acids Large straight chain hydrocarbon with a carboxyl group at one end Carboxyl Group – Hydrophilic Hydrocarbon Chain – Hydrophobic

50. Lipids Saturated Fatty Acid Unsaturated Fatty Acid