Introduction to Cell & Molecular Biology (BIOL121) - Dr. S.G. Saupe (ssaupe@csbsju.edu); Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321

General Chemistry Study Guide   

Required Readings:  Freeman Chapter 2

Supplemental Readings:  (copies available in the file box in the botany lab)

• Frieden, E. 1972. The Chemical Elements of Life.  Scientific American. June.  An interesting article concerning the elements of life, their function and factors in their selection.

•  Morowitz, H. 1979. The Six Million Dollar Man. In The Wine of Life.  A great essay concerning the molecular constituents of life and their relation to the laws of thermodynamics.

•  Morowitz, H. 1979. Manufacturing A Living Organism.  In The Wine of Life.  Another great essay concerning the possibility of creating life in a test tube.

•  Rensberger, B. 1980. Life In Limbo. Science 80.  A super essay about freezing and dehydration experiments.

Goal of The Unit: The goal of this unit is to study the basic chemical building blocks of living systems and to understand how they are arranged and held together.

Important Terms/Concepts: (Can you use them conversationally?)

Concept Map
       Prepare a concept map using the following terms:  atom, electron, polar bond, nucleus, proton, neutron, atomic number, mass number, isotope, orbital, covalent bond, hydrogen bond, inorganic, organic, ionic bond, carbon, hydrogen, nitrogen, valence

Specific Learning Objectives: Upon completion of this unit you should be able to):

1. Define atom, element, atomic number and mass number.  Use each in a sentence.

2. Describe the basic structure of an atom.
3. Describe how electrons are arranged in an atom.
4. Compare and contrast ionic, covalent and hydrogen bonding (i.e., strength, response in water, biological importance) and provide examples of each.
5. Explain the difference between single, double and triple covalent bonds.
6. Name the three or four most common elements in living systems.  What are some common elements in:  (a) the universe, (b) seawater and (c) the earth's crust.
7. Compare and contrast organic and inorganic.
8. Discuss the importance of carbon and why evolution favored carbon over silicon as the basis for life.
9. Explain why "proton" is a synonym for "hydrogen ion"
10. Explain what is meant by "functional group"
11. Explain the following symbols used in writing chemical structures: R
12. Identify the type of bond that holds together atoms in a functional group
13. Explain why carboxyl groups are acidic
14. Explain what it means that an atom is electronegative.  Give an example
15. Describe the difference between a polarized and non-polarized covalent bond
16. Name two atoms likely to participate in a polarized covalent bond (hint: nitrogen is one)
17. Identify the factors that led to favorability of C, H, O, N as the major elements in living systems. In other words, what's so special about them?  And what's not suitable about the other 90+ elements?
18. Explain what it means that "life is chemically unique".
19. Explain what determines the chemical properties of an atom
20. Compare and contrast hydrogen, tritium and deuterium.
21. Identify several biological functions of water
22. Describe the structure of a carbon atom.  Use such terms as energy shells (levels), orbitals, inner and outer shells, nucleus, valence, electrons, protons, neutrons, as many other terms as possible that are appropriate. 
23. Define isotope.  Give an example.  How are isotopes useful in biology?  Give some examples.  Explain why the chemical properties of a radioactive isotope are identical to the chemical properties of a non-radioactive isotope of the same element.
24. For each of the three major bond types - ionic, covalent and hydrogen - define each, indicate the strength of each, the response of each to water, and give examples of their function.  Explain why there is more than one type of bond; or in other words, why aren�t all bonds covalent?
25. Draw some atoms or molecules joined by:  covalent bonds; ionic bonds; hydrogen bonds
26. Explain the difference between single, double and triple covalent bonds.
27. Little Oblio, the boy in the Land of the Point, met the Rock People.  Explain why they couldn�t exist.  In other words, why couldn�t life be based on silicon?  When you are finished studying, rent the video (Harry Nillson) and relax.
28. Memorize the atomic number and mass number of the most common isotope of C, H, O, N.  Indicate the number of electrons and protons in each atom.  How many neutrons occur in each?  What is the maximum number of covalent bonds that each can form with another atom?
29. Define electronegative.  Give an example.
30. What is the difference between a polarized and non-polarized covalent bond?  Why do bonds become polarized?  Name the atoms most likely to participate in a polarized covalent bond.
31. If NASA sent you to Mars to search for life what elements would you look for and why?  What if you conclude if you found a little bit of carbon?  Or nitrogen?
32. Identify the factors that led to favorability of C, H, O, N as the major elements in living systems. In other words, what's so special about them? And what's not suitable about the other 90+ elements?

Sample Exam Questions:

1.  If an atom has a mass number of 15 and an atomic number of 7, then this atom would most likely possess _____ electrons,_____ protons and _____neutrons.
        A.   7, 8, 7
        B.    15, 7, 8
        C.   7, 7, 8
        D.   15, 15, 8
        E.    8, 15, 7

2.  Which one of the following elements is least common in living systems?
        A.   Carbon
        B.   Hydrogen
        C.   Oxygen
        D.   Nitrogen
        E.    Sulfur

3.  The number of ______ never varies among atoms of a specific element.
        A.  Protons
        B.  Neutrons
        C.  Electrons

4.  The number of ______ varies in the isotopes of an element.
        A.  Protons
        B.  Neutrons
        C.  Electrons

5.  The most ancient fossils found to date are approximately ______ years old.

6.  Which four elements make up 96% of matter found in living organisms?

7.  A cation has a ______ charge.
        a.  positive
        b.  negative
        c.  neutral

8.  In a reduction-oxidation reaction, a substance that loses electrons is _____.
        a.  oxidized        b.  reduced        c.  ionized