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

2. 2 Chemistry of Life

3. 3 Points to ponder How are living things organized from atoms to molecules? What is pH and how is it important to living organisms? What are the four macromolecules found in living organisms? What are the structure (subunits) and function of these four macromolecules? How are proteins organized and how is their shape important to their function? How are DNA and RNA similar and how are they different?

4. 4 Building blocks from large to small ______ is anything that has mass and takes up space. Elements are the basic building blocks of matter that _____ be broken down by chemical means. _____ are the smallest units of an element that retain the element’s physical and chemical properties. These bond together to form ________. 2.1 From Atoms to Molecules

5. 5 Elements Atomic symbol Atomic mass Atomic number 2.1 From Atoms to Molecules Figure 2.1 A portion of the periodic table of elements. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. I 1 H 2 V 345 B 6 C 7 N 8 O 9 F PS K atomic number atomic symbol atomic mass 1.008 LiNe He 4.003 VIII IIIIIIVVIVII 10 Be 20.1819.0016.0014.0112.016.9419.01210.81 1118 Na 22.99 19 39.10 24.31 Mg 12 Ar 39.95 1716151413 AlSiCl 35.4532.0730.9728.0926.98 20313233343536 83.60 Kr 79.90 Br 78.96 Se 74.92 As 72.59 Ge 69.72 Ga 40.08 Ca Periods 1 2 3 4 Groups

6. 6 Subatomic particles of atoms Neutrons are ______ (uncharged). Protons are _________ charged. Neutrons and protons make up the ________. Electrons are __________ charged and orbit around the _________. 2.1 From Atoms to Molecules

7. Figure 2.2 The atomic structure of select elements. Subatomic particles of atoms Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. 0 1 1 1p hydrogen H Subatomic Particles Atomic Mass Unit (AMU) ChargeParticle Proton Neutron Electron0 +1 –1 6p 6n 8p 8n 7p 7n oxygen O carbon C nitrogen N

8. 8 Isotopes 2.1 From Atoms to Molecules _________ are atoms that have the same atomic number but a different atomic mass because the number of neutrons differ. _____________ are useful in dating old objects, imaging body organs and tissues through X-rays, and killing cancer cells. Radiation can be harmful by damaging cells and DNA and/or causing cancer.

9. Isotopes 2.1 From Atoms to Molecules Figure 2.3 Medical uses for low-level radiation. Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. a. larynx thyroid gland trachea missing portion of organ a: © Biomed Commun./Custom Medical Stock Photo; b (patient): Courtesy National Institutes of Health; (brain scan): © Mazzlota et al./Photo Researchers, Inc. b.

10. 10 Molecules Made of atoms that are _______ together Can be made of the _______ atom or ______________ atoms 2.1 From Atoms to Molecules

11. 11 Ionic bonds Atoms in this type of bond donate or take on electrons Result in a stable ____________ Occur between particles that are charged (ions) 2.1 From Atoms to Molecules

12. 12 2.1 From Atoms to Molecules Figure 2.5 Formation of an ionic bond. Ionic bonds Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. + Cl – Na sodium atom (Na)chlorine atom (Cl) NaCl sodium ion (Na + ) sodium chloride (NaCl) chloride ion (Cl – ) b. Na + Cl – a. b(crystals, shaker): © Evelyn Jo Johnson

13. 13 Atoms in this type of bond _______ electrons Result in a stable ______________ 2.1 From Atoms to Molecules Covalent bonds

14. 14 2.1 From Atoms to Molecules Copyright © The McGraw-Hill Companies, Inc. Permission required for reproduction or display. + + b. When two oxygen atoms covalently bond, oxygen gas results. 8p 8n 8p 8n 8p 8n 8p 8n 1p 8p 8n 1p oxygen O 2 hydrogen 2H a. When an oxygen and two hydrogen atoms covalently bond, water results. water H 2 O oxygen O 2 oxygen gas O 2 oxygen O 2 8p 8n Figure 2.6 Covalent bonds. Covalent bonds