1. Introduction – Inorganic Chemistry Biology 2121

2. What we need to stay alive – Necessary Life Functions 1.Movement 2.Response to Stimuli – Nervous system 3.Digestion – Break down foodstuffs --------  absorb in blood ---  tissues and cells 4.Metabolism – Catabolic process vs. anabolic processes 5.Excretion – Digestive system (solid waste); urinary (liquid waste) 6.Reproduction – Asexual vs. sexual – Fertilization via gametes 7.Growth 8.Maintain Boundaries

3. To survive you must have the following 9. Nutrients to digest and absorb 10. Oxygen – Cellular Respiration in cells – produce ATP 11. Water – 60-80% of body weight; allows for chemical reactions; cell balance; solvent 12. Must maintain normal body temperature – 37 C or 98.6 F

4. Necessary Life Functions – Homeostasis Homeostasis: state of body equilibrium or to maintain a stable internal environment. – “Dynamic” process How it works – Variable – Stimulus – Receptor – Control center – Effector

5. Examples of Homeostatic Mechanisms 1.Negative Feedback Systems – Most prevalent – Variable relationship – inverse Original stimuli is lowered or shut down – Examples: Glucose control; Body Temperature 2.Positive Feedback Systems – Original stimuli is enhanced – Examples: Blood Clotting; oxytocin

6. Introduction – Inorganic Chemistry Organization of the Human Body – Levels of Structural Organization

7. Basics of Chemistry – Atomic Structure Atomic Structure – Nucleus Protons (+) and Neutrons (0) – Both weight 1.0 amu – Energy Levels Electrons (-) – <1 amu (1/2000) Atoms make up Elements – Same types of atoms (Fe, Cu, etc.) – Elements form compounds and molecules Not all atoms of the same kind are alike – Isotopes

8. Electrons Interact to form Chemical Bonds Valence Electrons – Atomic Number – Atomic number: number of protons = number of electrons – Valence: most outer shell electrons that react with other atoms Identifying valence electrons: Group Number Ions: when an atom gains or loses an electron Metals and Nonmetals – Location on the periodic table – Formation of Ions – Metals: tend to lose electrons Positive ions or cations – Nonmetals: gain electrons Form negative ions or anions Ion Attraction – Electrostatic attraction – Forms Ionic Bonds

9. Ionic and Covalent Bonds 1.Ionic Bonds – Formed via electrostatic attraction Metals (cations) and Nonmetal (anions) Electronegativity – Crystalline solids – Salts: NaCl; MgCl 2 (Electrolytes) – Importance of ions/electrolytes 2.Covalent Bonds – Similar electronegativity – Nonmetals – Forms molecules Importance of molecules and covalent compounds

10. Covalent Compounds – Polarity Covalent compounds – Slight charges are formed during the sharing of electrons – Equal Sharing “nonpolar” No slight charges formed – Unequal Sharing “polar” Slight differences in EN – charges Forms two poles or “dipole” Water – Polar Covalent Compound – Universal Solvent – Chemical reactions

11. Hydrogen Bonding Covalent polar compounds form a ‘weak’ bond. Attraction between dipoles Intramolecular bond – Holds a molecule to a molecule Significance of Hydrogen bonding – DNA: holds double strand together – Proteins

12. Chemical Reactions – Human Body Chemical Reactions produce new substances Chemical Reactions in the Human Body – Anabolic – “Build up” – Catabolic – “Break down” – Metabolic pathways (Glycolysis, Kreb’s Cycle, etc.) Chemical Reactions are mediated by Enzymes – Biological Catalysts – Speed up chemical reactions Types of Chemical Reactions – Synthesis amino acids combine to make proteins – Decomposition Starch(glycogen) broken down to produce glucose – Exchange or displacement

13. Chemical Reactions Synthesis Reaction – Energy consuming or absorbing “Endergonic” “Anabolic” Decomposition Reaction – Energy Releasing “Exergonic” “Catabolic” EA – Energy of Activation

14. Factors that Affect Chemical Reactions 1.Temperature – >Temperature faster the reaction speed – Increase in KE 2.Concentration – >Concentration the faster the reaction speed – Greater chances of collisions 3.Size of Particles – Smaller the particles faster the reaction speed – Collides more often 4.Catalysts – Lowers the activation energy; reaction takes place with less energy.

15. Mixtures and Solutions Human body is made of many mixtures Mixture vs. Chemical Reaction Types of Mixtures – 1. Solution – 2. Colloids – 3. Suspensions Solutions – “Homogeneous” – same composition throughout – Solvent vs. Solute – Water is solvent “aqueous” solution Water dissolves gases, liquids and solids – Example: Blood Plasma – Concentration: % or Molarity

16. Mixtures and Solutions Colloids or “emulsions” – “Heterogeneous” – “Sol-Gel” transformation – Example: Cytosol in cytoplasm of cells Suspensions – “Heterogeneous” – Example: Blood

17. Electrolytes in the Body Salts, Acids and Bases are “electrolytes” 1.Salts – Ionic compound that contains a cation other than a H+ and an anion other than a hydroxyl ion (OH-): NaCl – Common salts in the body: NaCl; CaCO 3 ; KCl 2.Acids – Releases H+ in solution – “Proton donor” – Lowers pH 3.Bases – Releases OH- in solution – “Proton acceptors” – Raises pH HCl releases H +

18. Acids and Bases in the Body Acids – Hydrochloric Acid (HCl) – digestion Bases – Act as buffers – “acid-base homeostasis” – Bicarbonate ion

19. pH Scale pH = “Power of Hydrogen” Concentration of hydrogen ions Expressed in terms of moles/L or Molarity Logarithmic – One pH unit represents a 10-fold change in ion concentration – pH of a solution is the negative log of the concentration of hydrogen ions – Scale: 0-14 pH = - log [H + ] pH scale Animation

20. pH Scale