Molecules of Life

1. Molecules of Life Chapter 2 & 3

2. Water properties • Unique properties based on its structure • Oxygen is more electronegative than hydrogen • Electrons spend more time with oxygen than with hydrogen • Polar covalent bond • ie unequal sharing

3. Water Properties • Unique properties based on its polarity • Oxygen more electronegative than hydrogen results in unequal sharing of electron Slight polar ends

4. Polarity of Water causes “stickiness” Water molecules “stick” to each other in distinct patterns resulting in organization of molecules

5. Why is polarity important? • Polarity causes molecules to interact in unique ways that influence life • Encourages formation of hydrogen bonds

6. Water molecules tendency to “stick” to each other Forms hydrogen bonds in 3-d Results in surface tension Cohesion Why is surface tension important…

7. Surface Tension in Biology “Jesus Lizard” http://www.visionlearning.com/library/module_viewer.php?mid=57 http://www.youtube.com/watch?v=WpXHpXKZtws

8. Surface Tension in Biology

9. Surfactants • Molecules that disrupt cohesion amongst water molecules

10. Surfactants Don’t wash your car in the creek or dump soap down the storm wash!

11. Water molecules tendency to “stick” to other polar molecules Adhesion

12. Cohesion & Adhesion Adhesion Cohesion

13. Capillary ActionCohesion & Adhesion

14. Water Transport

15. Terminology • Heat= amount of energy associated with the movement of atoms and molecules in matter • Temperature= measures the intensity of heat • 1 calorie is the amount of energy to raise 1 gram of water 1 degree Celcius

16. High Specific Heat • H bonds retard motion at atomic level • Resists heating • Water has a high heat capacity • Stabilize temperatures • Keeps your body temperature stabilized • Keeps environmental temperature stabilized

17. Water Resists Heating

18. High Heat of Vaporization • Relatively large amount of Energy removed when changing water from liquid to gas form • ~600 calories • Lots of Energy required to break H bonds • Important in an organisms ability to moderate its temperature • Evaporative cooling

19. Evaporative Cooling • Aids in homeostasis maintenance

20. Physical Properties of Water • Density • Density increases as temp decreases • Water max density 4 degrees C • Molecules move apart Ice floats! water steam ice

21. Density Properties Nutrient Cycling

22. Solvent Properties • Solvent properties • Protects ions from one another • Charged substances dissolve • Universal solvent

23. Interactions with Water • Hydrophillic • Polar or charged • Hydrophobic • nonpolar

24. Summary of Water’s Properties • Cohesion & Adhesion • Capillary action • Interaction of cohesion & adhesion in small spaces • Moderation of temperature • High specific heat • High heat of vaporization • Density properties • Solvent properties • Hydrophillic vs hydrophobic

25. Molecule Structure • Monomers • Polymers • Macromolecules

26. Molecule Formation • Dehydration synthesis • Connection of monomers through covalent bond that yields water • Hydrolysis • Disassembly of polymer into component monomers with the use of water molecule to break covalent bonds

27. Organic Molecules • Why is carbon so important? • Large, complex, diverse molecules • Abundance of carbon based molecules

28. Carbon • Reactive • Covalent bonds • Carbon branches (backbones)

29. Carbon Molecules have Complex Shapes In Biology Shape Maters!!

30. Carbon Based Molecules • Hydrocarbons • Carbohydrates • Lipids • Proteins • Nucleic Acids

31. Hydrocarbons • Simplest compounds • Only 2 elements • Carbon • Hydrogen • Different numbers of each element • Ex. Methane CH4 • Unique shape • Shape matters • Physiological importance • Energy rich • Communication • http://www.youtube.com/watch?v=SqGPvxzz50Q

32. Silverfish and Army Ant • Silverfish use hydrocarbons to mask scent • Access to shelter & food • http://www.sciencedaily.com/releases/2011/11/111130202559.htm

33. What happens when we add different types of elements to hydrocarbons?

34. Functional Groups • Groups of atoms that participate in chemical reactions • Influence nature of molecule • Characteristic of carbon molecule types

35. Carbohydrate Characteristics • Sugar molecules • Energy sources • Hydrophyllic • Structure • 1:2:1 ratio CH2O • Monomers or polymers • Monosaccharides • Disaccharides • Polysaccharides Monosaccharides are rings in aqueous solutions

36. Monosaccharides • Simple sugars • Basic building blocks for organic molecules • Primary cellular energy • CH2O • Ex. Glucose & fructose C6H12O6

37. IsomersGlucose vs fructose

38. Disaccharides • 2 monosaccharides • Formed via dehydration synthesis

39. Polysaccharides • Aka complex carbohydrates • Hydrophyllic • Polymers of monosaccharides (3+) • Examples • Starch • Glycogen • Cellulose

40. Lipids • Most with no polar regions= hydrophobic (insoluble) • Triglycerides • Fats, waxes, oils • Glycerol & 3 fatty acids • Phospholipids • Steroids 3 fatty acids

41. Insulation • Reduces heat loss

42. Dietary Fats • Excellent energy source • 2X E of Carbs or proteins • Fat • solid at room temperature • Oils • liquid at room temperature • Hydrogenation= solid • Flavor foods • Slow digestion

43. Types of Fats • Saturated fats • H atoms at all sites • Ex. Lard, butter, solid fats

44. Types of fats • Unsaturated fats • Lacking one H atom • Ex. Olive oil, nuts, avocado

45. Health Implications • Saturated fats • Animal fats • Max # of H atoms ie no double bonds= parallel arrays • Unsaturated fats • Veggie oils • 1+ double bonds = kinks

46. Waxes • Minimizes evaporation • Protection • Coat leaves, fruits, skin, feathers, fur, ears • 1 fatty acid connected with alcohol • +++++ hydrophobic

47. Phospholipid Membrane • Provides structure for cell membrane

48. Steroid Hormones • Hydrophobic • Cholesterol fundamental unit • Cell membranes • Sex hormones

49. Small difference amongst molecules can result in big differences Testosterone Estrodiol

50. Protein • Polymers of Amino acid • Complex 3D structure