1. Memmler’s A&P Chap 2 Chemistry, matter, and life

2. Chemistry p20 Study of composition and properties of matter. Matter is anything that takes up space. Elements: substances that make up matter. Atoms: subunits of elements Common chemical elements in the body: – Oxygen O2 – Carbon C – Hydrogen H – Nitrogen N – Calcium Ca – Potassium K – Sodium Na – Iron Fe

3. Atoms p20 Atomic structure: – Nucleus Protons Neutrons – Orbiting around the nucleus of the atom in energy levels are electrons.

4. Compounds p21 Substances composed of two or more different elements are called compounds The picture is of a molecule of water.

5. Mixtures p22 – Solutions: mixture formed when one substance dissolves in another Solvent: liquid part Solute: solid part Aqueous solution: solution that has water as the solvent Example: saline – Suspensions: non-uniform mixture. The particles will settle out of the solvent. Example: milk of magnesia – Colloids: molecules do not dissolve, but remain evenly distributed in the suspending material Example: cytosol

6. Electrolytes p23 Electrolytes: ionically bonded substances separate into charged particles when they go into solution Note: in practice, the term electrolytes is also used to refer to the ions themselves in body fluids. Examples: Na+, K+, Cl-, Ca++

7. pH scale p24-26 Physiologic normal pH for blood and body fluids is 7.35-7.45 pH less then 7.35 is called acidosis pH higher than 7.45 is called alkalosis Buffers are chemicals that prevent rapid changes in H+ ion concentrations.

8. Organic compounds p27 Contain carbon Main types of organic compounds: carbohydrates: monosaccharide example: glucose lipids: (fats): glycerol + fatty acid example: triglycerides, steroids, cholesterol proteins: amino acids Nitrogen is provided in the diet in proteins.

9. Enzymes p28-30 Enzymes are catalysts: increase the speed of a chemical reaction without being changed or used up by the reaction. Names of enzymes end with –ase.