Concepts of Biology (BIOL115) - Dr. S.G. Saupe (ssaupe@csbsju.edu); Biology Department, College of St. Benedict/St. John's University, Collegeville, MN 56321

Chemistry Study Guide

Required Readings:  Purves, et al (2001). Chapter 2 & 3.

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, the universe, seawater and the earth's crust.
7. Explain why water is critically important for life.
8. Discuss the significance of hydrogen bonds and the polarity of water for the properties of water.
9. Describe, define or explain each of the following properties of water: surface tension, specific heat, heat of vaporization, density, compressibility, liquid at room temperature, heat of fusion and solvent ability.  Give examples of each.  Especially indicate the biological importance of each.
10. Define adhesion and cohesion
11. Explain what is meant by pH and why it is important.
12. Compare and contrast acids and bases and provide examples of each.
13. Explain the significance of buffers.  Explain how the carbonic acid - bicarbonate buffer in the blood system works
14. Compare and contrast organic and inorganic.
15. Discuss the importance of carbon and why evolution favored carbon over silicon as the basis for life.
16. Identify and name the common functional groups (methyl, hydroxyl, carboxyl, amino, carbonyl, phosphate) and the molecules in which they occur (alcohols, organic acids, ketone, aldehydes).
17. Explain the statement: `Life is polymeric'
18. List the major macromolecules in living systems, their major functions, and their building blocks.
19. Recognize the chemical structures of the macromolecules of life.
20. Compare and contrast hydrolysis and condensation (dehydration synthesis) reactions.
21. Compare and contrast starch, glycogen, cellulose, chitin and sucrose.
22. Distinguish between the primary, secondary, tertiary and quarternary structure of proteins. 
23. Describe how these structures are determined and maintained.
24. Compare and contrast triglyceride, phospholipid, wax and steroid.
25. Distinguish between a globular and fibrous protein.
26. Answer questions at the end of the chapter
27. Explain why "proton" is a synonym for "hydrogen ion"
28. Explain what is meant by "functional group"
29. Explain the following symbols used in writing chemical structures: R
30. Identify the type of bond that holds together atoms in a functional group
31. Explain why carboxyl groups are acidic
32. Give the atomic number of C, H, O, N.  Indicate the number of electrons and protons in each atom. Give the mass number of the most common isotope.  Indicate the number of neutrons in each.  Indicate the maximum number of covalent bonds that each forms with other atoms.
33. Explain what it means that an atom is electronegative.  Give an example
34. Describe the difference between a polarized and non-polarized covalent bond
35. Name two atoms likely to participate in a polarized covalent bond (hint: nitrogen is one)
36. 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?
37. Explain what it means that "life is chemically unique".
38. Explain what determines the chemical properties of an atom
39. Compare and contrast hydrogen, tritium and deuterium.
40. Identify several biological functions of water
41. 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. 
42. 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.
43. 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?
44. Draw some atoms or molecules joined by:  covalent bonds; ionic bonds; hydrogen bonds
45. Explain the difference between single, double and triple covalent bonds.
46. Name the three or four most common elements in each of the following: organism, the universe as a whole, seawater, earth's crust.
47. 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.
48. 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?
49. Define electronegative.  Give an example.
50. 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.
51. What does it mean that "life is chemically unique".
52. 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?
53. 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.  Perspiration can be used as a mechanism to cool organisms because water
           A. is incompressible.
           B. has a high surface tension.
           C. has a high heat of vaporization.
           D. is a liquid at room temperature.
           E. has a high specific heat (heat capacity).

2.  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

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