1. 1 Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 2 Chemistry of Life Lecture Outline Part 2 Human Biology Sylvia S. Mader Michael Windelspecht

2. 2 What are the properties of water? Water is liquid at _______________. Liquid water _________ change temperature quickly. Water has a high heat of _____________. Frozen water is less _______ than liquid water. Molecules of water cling together. Water is a ________ for polar molecules. 2.2 Water and Life

3. 3 What bond holds water molecules together? ________________ occur between a hydrogen in a covalent bond and a negatively charged atom. These are relatively _____ bonds. 2.2 Water and Life H H Hydrogen bonding between water molecules O hydrogen bond  +  - Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 2.7b Hydrogen bonds and water molecules.

4. 4 Acids and bases Acids are substances that dissociate and release ________________ Bases are substances that take up _______________ or release __________ __________ 2.2 Water and Life

5. 5 What is the pH scale? A measure of hydrogen ion (H + ) _____________ Working scale is between 0 and 14 with 7 being neutral A pH below 7 is ______ and above 7 is ______ The concentration of hydrogen ions between each whole number changes by a __________ 2.2 Water and Life

6. 6 Looking at the pH scale 2.2 Water and Life H+H+ OH – Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. acidic basic stomach acid, lemon juice vinegar, cola, beer 1 0 2 3 4 5 6 7 8 9 H + Ion Concentration pH ValueExamples hydrochloric acid tomatoes black coffee urine pure water seawater baking soda Great Salt Lake household ammonia household bleach sodium hydroxide 10 -1 10 0 10 -3 10 -4 10 -5 10 -6 10 -7 10 -8 10 -9 10 -10 10 -11 10 -12 10 -13 10 -14 10 -2 14 13 12 11 10 Figure 2.10 The pH scale.

7. 7 Making and breaking down organic molecules __________________ – the removal of water that allows subunits to link together into larger molecules ________________ – the addition of water that breaks larger molecules into their subunits 2.3 Molecules of Life

8. 8 How do we build and break down organic molecules? 2.3 Molecules of Life Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. subunit hydrolysis reaction subunit dehydration reaction subunit H H2OH2O H2OH2O b. a. OH H Figure 2.11 The breakdown and synthesis of macromolecules.

9. 9 What organic molecules are found in living organisms? 1. Carbohydrates 2. Lipids 3. Proteins 4. Nucleic acids 2.3 Molecules of Life

10. 10 1. What are carbohydrates? Made of subunits called ________________ Made of C, H, and O in which the H and O atoms are in a 2:1 ratio Function as short- and long-term ________ _________ Found as simple and complex forms 2.4 Carbohydrates

11. 11 ________________ – 1 carbon ring as found in glucose ______________ – 2 carbon rings as found in maltose What are simple carbohydrates? 2.4 Carbohydrates OH OH H H H H HO C 6 H 12 O 6 OH H O C C C C C 4 5 6 3 2 1 OHH H H CH 2 OH H O O OHHO OH CH 2 OH maltose OO O C 12 H 22 O 11 CH 2 OH Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Figure 2.12 The synthesis and breakdown of a disaccharide.

12. 12 What are complex carbohydrates? Polysaccharides are made of many _____ _______ _________ is the storage form in animals. Starch is the storage form in plants. 2.4 Carbohydrates Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. O H O O O H H H OHH starch granule cell wall potato cells nonbranched branched HOHH H H OO H O H H H H H O HHHHH O CH 2 OH © Jeremy Burgess/SPL/Photo Researchers, Inc. Figure 2.13 Starch is a plant complex carbohydrate.

13. 13 2. What are lipids? Molecules that do not ________ in water Used as energy molecules Found in cell _____________ Found as fats and oils, phospholipids, and steroids 2.5 Lipids

14. 14 How are fats and oils different? Fats Usually ______ origin _______ at room temperature Function for long-term energy storage, insulation from heat loss, and cushion for organs Oils Usually ______ origin _______ at room temperature 2.5 Lipids

15. 15 What is the structure of fats and oils? A glycerol molecule and 3 fatty acid tails 2.5 Lipids Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. C C HHHHHH C HHH CCC H C C H C H HHHH C HH C H C + C H H 3 fatty acidsglycerolfat molecule3 water molecules dehydration reaction OH H H H H H C C C HHHH H CCCCC O HO O O HHH HCCCCC HHHHH HHHHHH HCCCCCC + H H H H H HHH HCCCCCC HHHHHO HHHHO HHHHHOH H C C C O O O 3 H 2 O H C hydrolysis reaction Figure 2.16 Structure of a triglyceride.