Chapter 2 Chemical Basis of Life Molecular model of a Phospholipid PowerPoint Presentation to accompany Hole’s Human Anatomy and Physiology, 10 th edition , edited by S.C. Wache for Biol2064.01
You are responsible for the following figures and tables : Tab. 2.1 - important definitions. Tab. 2.3 - the first ten elements of the periodic table of elements, TB, p. 969. Fig. 2.3 - Learn how to distribute proteons and electrons Fig. 2.4 - learn how to distribute protons and electrons Fig. 2.8 - hydrogen bonds; example H 2 O. Fig. 2.6 - examples of structural and molecular formulas Read TB, p.44, on chemical reactions. Define 'isotope'. Tb, p.39. See Clin. Appl. 2.1, TB, p. 41. W hat is 131 I used for ? Tab. 2.4, 2.5; Fig. 2.10 - Study pH, bases and acids. Tab. 2.6: small inorganic molecules like water and carbon dioxide Tab. 2.8 – Macromolecules. Fig. 2.11 and 2.12; Fig. 2.15 and 2.16; Fig. 2.17 and 2.18 - note the formation of the covalent bond; Fig. 2.21.
Atoms that have the same atomic number, but different atomic weights are isotopes.
For example, 131 I and 125 I are isotopes of iodine (see textbook, Clinical Applications 2.1).
131 I is a heavy radioactive isotope of iodine that has the mass number 131 and a half-life of eight days. It emits beta particles and gamma rays, and is used especially in the form of its sodium salt in the diagnosis of thyroid disease and the treatment of goiter.
125 I is a light radioactive isotope of iodine that has a mass number of 125 and a half-life of 60 days. It gives off soft gamma rays, and is used as a tracer in thyroid studies and as therapy in hyperthyroidism.
Atomic number is the number of protons. It is the same for all atoms of an element.
Atomic weight is the number of protons and neutrons.