1. Unit 7 HS260 Anatomy, Physiology & Chemistry Amy Habeck, RD, MS, LDN 1

2. Questions? 2

3. Objectives Answer your questions Review ▫Chapter 2, Thibodeau & Patton: Structure and Function-Chemistry of Life ▫Chapter 1, Zumdahl: Basic Chemistry-An Introduction 3

4. Define chemistry 4

5. Chemistry: the science that deals with the materials of the universe and the changes that these materials undergo 5

6. What is the difference between physical and chemical changes? Physical changes: Chemical changes: 6

7. What are some examples of chemical changes? 7

8. Wood burns in air, forming water, carbon dioxide and other substances A plant grows by assembling simple substances into more complex substances The steel in a car rusts Emissions from a power plant lead to the formation of acid rain. 8

9. Quantitative vs Qualitative Observations Quantitative observations deal with amounts Qualitative observations deal with things that cannot be measured 9

10. Scientific Thinking Every-day LifeScientific Problems Recognize the problem Propose possible solutions Decide which solution is best Make an observation Formulate a hypothesis Perform an experiment 10

11. Scientific Thought What is a theory? What is an observation? What is a law? 11

12. Scientific Thought What is a theory? ▫A set of tested hypotheses that gives an overall explanation of some part of nature ▫An interpretation or possible explanation of why nature behaves in a particular way What is an observation? ▫Something that is witnessed and can be recorded What is a law? ▫A summary of observed behavior 12

13. Blood pH – case study Cindy, 5 years old, has been ill for several days with nausea and vomiting. ▫What is the pH of stomach fluid? ▫What is she losing, acid or base? 13

14. Factors Affecting Blood pH regulation Lungs Kidneys GI tract 14

15. Questions? 15

16. Slide 16 LEVELS OF CHEMICAL ORGANIZATION Atoms (Figure 2-1) Fill in the blanks ▫______________ —central core of atom  ______________—positively charged particle in nucleus  ______________—non-charged particle in nucleus  ______________—number of protons in the nucleus; determines the type of atom  ______________—number of protons and neutrons combined ▫______________—regions surrounding atomic nucleus  ______________ —negatively charged particle

17. Slide 17 LEVELS OF CHEMICAL ORGANIZATION Atoms (Figure 2-1) ▫Nucleus—central core of atom  Proton—positively charged particle in nucleus  Neutron—non-charged particle in nucleus  Atomic number—number of protons in the nucleus; determines the type of atom  Atomic mass—number of protons and neutrons combined ▫Energy levels—regions surrounding atomic nucleus that contain electrons  Electron—negatively charged particle  May contain up to eight electrons in each level  Energy increases with distance from nucleus

18. Slide 18

19. Slide 19 LEVELS OF CHEMICAL ORGANIZATION Elements, molecules, and compounds (Figure 2-2) Fill in the blanks ▫________—a pure substance; made up of only one kind of atom ▫________—a group of atoms bound together in a group ▫________—substances whose molecules have more than one kind of atom

20. Slide 20 LEVELS OF CHEMICAL ORGANIZATION Elements, molecules, and compounds (Figure 2-2) ▫Element—a pure substance; made up of only one kind of atom ▫Molecule—a group of atoms bound together in a group ▫Compound—substances whose molecules have more than one kind of atom

21. Slide 21

22. Slide 22 CHEMICAL BONDING Chemical bonds form to make atoms more stable ▫Outermost energy level of each atom is full ▫Atoms may share electrons or donate or borrow them to become stable

23. Slide 23 CHEMICAL BONDING Ionic bonds ▫Ions form when an atom gains or loses electrons in its outer energy level to become stable  _____ ion—has lost electrons; indicated by superscript positive sign(s), as in Na + or Ca ++  ______ion—has gained electrons; indicated by superscript negative sign(s), as in Cl  ▫Ionic bonds form when positive and negative ions attract each other because of electrical attraction ▫________—molecule that dissociates (breaks apart) in water to form individual ions; an ionic compound

24. Slide 24 CHEMICAL BONDING Ionic bonds ▫Ions form when an atom gains or loses electrons in its outer energy level to become stable  Positive ion—has lost electrons; indicated by superscript positive sign(s), as in Na + or Ca ++  Negative ion—has gained electrons; indicated by superscript negative sign(s), as in Cl  ▫Ionic bonds form when positive and negative ions attract each other because of electrical attraction ▫Electrolyte—molecule that dissociates (breaks apart) in water to form individual ions; an ionic compound

25. Slide 25 CHEMICAL BONDING ▫_________ bonds form when atoms share their outer energy to fill up and thus become stable ▫_________ bonds do not ordinarily easily dissociate in water

26. Slide 26 CHEMICAL BONDING Covalent bonds (Figure 2-3) ▫Covalent bonds form when atoms share their outer energy to fill up and thus become stable ▫Covalent bonds do not ordinarily easily dissociate in water

27. Slide 27

28. Slide 28 INORGANIC CHEMISTRY 1._________ molecules contain carbon- carbon covalent bonds or carbon- hydrogen covalent bonds 2._________ molecules do not contain carbon-carbon covalent bonds or carbon- hydrogen covalent bonds Examples of inorganic molecules: water and some acids, bases, and salts

29. Slide 29 INORGANIC CHEMISTRY Organic molecules contain carbon-carbon covalent bonds or carbon-hydrogen covalent bonds inorganic molecules do not Examples of inorganic molecules: water and some acids, bases, and salts

30. Slide 30 INORGANIC CHEMISTRY Water ▫Water is a solvent (liquid into which solutes are dissolved), forming aqueous solutions in the body ▫Water is involved in chemical reactions (Figure 2-4) 1.__________—chemical reaction in which water is removed from small molecules so they can be strung together to form a larger molecule 2.__________—chemical reaction in which water is added to the subunits of a large molecule to break it apart into smaller molecules  Chemical reactions always involve energy transfers, as when energy is used to build ATP molecules  Chemical equations show how reactants interact to form products; arrows separate the reactants from the products

31. Slide 31 INORGANIC CHEMISTRY Water ▫Water is a solvent (liquid into which solutes are dissolved), forming aqueous solutions in the body ▫Water is involved in chemical reactions (Figure 2-4)  Dehydration synthesis—chemical reaction in which water is removed from small molecules so they can be strung together to form a larger molecule  Hydrolysis—chemical reaction in which water is added to the subunits of a large molecule to break it apart into smaller molecules  Chemical reactions always involve energy transfers, as when energy is used to build ATP molecules  Chemical equations show how reactants interact to form products; arrows separate the reactants from the products

32. Slide 32

33. Slide 33 INORGANIC CHEMISTRY Acids, bases, and salts ▫Water molecules dissociate to form equal amounts of H + (hydrogen ion) and OH  (hydroxide ion) 1._______—substance that shifts the H + /OH  balance in favor of H + ; opposite of base 2._______—substance that shifts the H + /OH  balance against H + ; also known as an alkaline; opposite of acid

34. Slide 34 INORGANIC CHEMISTRY Acids, bases, and salts ▫Water molecules dissociate to form equal amounts of H + (hydrogen ion) and OH  (hydroxide ion) ▫Acid—substance that shifts the H + /OH  balance in favor of H + ; opposite of base ▫Base—substance that shifts the H + /OH  balance against H + ; also known as an alkaline; opposite of acid

35. Slide 35 INORGANIC CHEMISTRY Acids, bases, and salts (cont.) ▫pH—mathematical expression of relative H + concentration in an aqueous solution (Figure 2-5)  pH 7 is neutral (neither acid nor base)  pH values above 7 are basic; pH values below 7 are acidic 1.____________ occurs when acids and bases mix and form salts 2.____________ are chemical systems that absorb excess acids or bases and thus maintain a relatively stable pH

36. Slide 36 INORGANIC CHEMISTRY Acids, bases, and salts (cont.) ▫pH—mathematical expression of relative H + concentration in an aqueous solution (Figure 2-5)  pH 7 is neutral (neither acid nor base)  pH values above 7 are basic; pH values below 7 are acidic ▫Neutralization occurs when acids and bases mix and form salts ▫Buffers are chemical systems that absorb excess acids or bases and thus maintain a relatively stable pH

37. Slide 37

38. Slide 38 ORGANIC CHEMISTRY Carbohydrates—sugars and complex carbohydrates (Figure 2-6) ▫Contain carbon (C), hydrogen (H), oxygen (O) ▫Made up of six-carbon subunits called ____________ or single sugars (e.g., glucose) ▫Disaccharide—double sugar made up of two monosaccharide units (e.g., sucrose, lactose) ▫Polysaccharide—complex carbohydrate made up of many monosaccharide units (e.g., glycogen made up of many glucose units) ▫Function of carbohydrates is to store energy for later use

39. Slide 39 ORGANIC CHEMISTRY Carbohydrates—sugars and complex carbohydrates (Figure 2-6) ▫Contain carbon (C), hydrogen (H), oxygen (O) ▫Made up of six-carbon subunits called monosaccharides or single sugars (e.g., glucose) ▫Disaccharide—double sugar made up of two monosaccharide units (e.g., sucrose, lactose) ▫Polysaccharide—complex carbohydrate made up of many monosaccharide units (e.g., glycogen made up of many glucose units) ▫Function of carbohydrates is to store energy for later use

40. Slide 40

41. Slide 41 ORGANIC CHEMISTRY Lipids—fats and oils ▫Triglycerides (Figure 2-7)  Made up of one glycerol unit and three fatty acids  Store energy for later use ▫Phospholipids (Figure 2-8)  Similar to triglyceride structure, except with only two fatty acids, and with a phosphorus-containing group attached to glycerol  The head attracts water and the double tail does not, thus forming stable double layers (bilayers) in water  Form membranes of cells ▫Cholesterol  Molecules have a steroid structure made up of multiple rings  Cholesterol stabilizes the phospholipid tails in cellular membranes and is also converted into steroid hormones by the body

42. Slide 42

43. Slide 43

44. Slide 44

45. Slide 45 ORGANIC CHEMISTRY Proteins (Figure 2-9) ▫Very large molecules made up of amino acids held together in long, folded chains by peptide bonds ▫Structural proteins  Form structures of the body  Collagen is a fibrous protein that holds many tissues together  Keratin forms tough, waterproof fibers in the outer layer of the skin

46. Slide 46

47. Slide 47 ORGANIC CHEMISTRY Proteins (cont.) ▫Functional proteins  Participate in chemical processes  Examples: hormones, cell membrane channels and receptors, enzymes  Enzymes (Figure 2-10)  Catalysts—help chemical reactions occur  Lock-and-key model—each enzyme fits a particular molecule that it acts on as a key fits into a lock ▫Proteins can combine with other organic molecules to form glycoproteins or lipoproteins

48. Slide 48

49. Slide 49 ORGANIC CHEMISTRY Nucleic acids ▫Made up of nucleotide units ▫Sugar (ribose or deoxyribose) ▫Phosphate  Nitrogen base (adenine, thymine or uracil, guanine, cytosine)

50. Slide 50 ORGANIC CHEMISTRY Nucleic acids (cont.) ▫DNA (deoxyribonucleic acid) (Figure 2-11)  Used as the cell’s “master code” for assembling proteins  Uses deoxyribose as the sugar and A, T (not U), C, and G as bases  Forms a double helix shape ▫RNA (ribonucleic acid)  Used as a temporary “working copy” of a gene (portion of the DNA code)  Uses ribose as the sugar and A, U (not T), C, and G as bases ▫By directing the formation of structural and functional proteins, nucleic acids ultimately direct overall body structure and function

51. Slide 51

52. Questions? 52

53. Farewell Thank you for your kind attention and participation! Email any time -ahabeck@kaplan.edu Call if your matter is urgent ▫630 323 3307 Follow me on Twitter ▫@ProfAmyH 53