2001 #4  2001 All Questions     Scoring Guidelines      Sample Responses Q4
Composition/levels of structure in proteins
Roles of DNA/RNA in protein synthesis
Roles of proteins in membrane structure/transport

OLD FRQ's  prior to 1995

(1996)  The unique properties (characteristics) of water make life possible on Earth.  Select three properties of water and:
        a.     for each property, identify and define the property and explain it in terms of the physical/chemical nature of water.
        b.    for each property, describe one example of how the property affects the functioning of living organisms.

(1991)    Carbon is a very important element in living systems.
        a.     Describe the various characteristics of the carbon atom that make possible the building of a variety of biological molecules.
        b.     Explain how reactions involving carbon-containing compounds can contribute to the greenhouse effect.
       c.     The following structures are examples of two different categories of biological compounds.
               Describe how each category of compounds is important to the structure and functions of living systems. 

                                Category I                                                             Category II

               A drawing of a phospholipid*                     A drawing of an amino acid

*Drawings not available

(1994)    Enzymes are biological catalysts.
        a.     Relate the chemical structure of an enzyme to its specificity and catalytic activity.
        b.     Design a quantitative experiment to investigate the influence of pH or temperature on the activity of an enzyme.
        c.     Describe what information concerning the structure of an enzyme could be inferred from your experiment.

  (1981)    Discuss the biological importance of each of the following organic compounds in relation to cellular structure and function in plants and animals.
     a. Carbohydrates  
     b. Proteins   
     c.  Lipids  
     d. Nucleic Acids

(1978) Give specific examples to illustrate the theory of enzyme action, and include in your discussion the effects of each of the following:
        a.     Substrate concentration
        b.     pH shifts
        c.     Temperature shifts
        d.     Competitive inhibition.

(1975)    Describe the chemical compositions and configuration of enzymes and discuss the factors that modify enzyme structure and/or function.

1973)    Hypotheses derived from laboratory experiments and field observations have been advanced to explain the origin of life on earth. Starting with a probable prelife environment, describe the formation and evolution of the various trophic forms (nutrition types) to and including unicellular organisms. Describe at least one experiment whose results support one of these scientific hypotheses.

(1972)    A class of biology students performed an experiment on the digestion of starch by salivary amylase. Each student determined the length of time required for different dilutions of his saliva to digest completely a standard concentration of starch. Iodine was used to test for the presence of starch. The results obtained by some of the class are summarized in the table below.  

TIME REQUIRED FOR THE DISAPPEARANCE OF STARCH WITH VARIOUS SALIVA DILUTIONS(saliva: H2O)

Student                1:9 (10%)                1:19 (5%)              1:49 (2%)              1:99 (1%)

        A                     45 seconds            50 seconds            100 seconds          135 seconds
        B                     (no end point)
        C                     90 seconds            100 seconds          200 seconds          270 seconds
        D                     260 seconds          300 seconds          600 seconds          800 seconds

        a.     Present the data for Student A in graphic form.
        b.     Carefully examine the data collected by the four students above and state as many conclusions as you can that are supported by these data.
        c.     Assuming there have been no errors in techniques, form as many hypotheses as you can to explain the differences observed.
        d.     Design one experiment to test the validity of one hypothesis. Clearly state what data you would want to collect in this experiment to test your hypothesis.

(1969)    Proteins functioning as enzymes exhibit precise specifications. Discuss the levels of structural organization within proteins which are responsible for specific molecular interaction.    

(1968)    Suppose that you have isolated an extract from a tissue and you have found that the extract speeds up the rate of a particular reaction. What kind of information would you need to demonstrate that the substance responsible for increasing the rate of this reaction is an enzyme? Explain how this information would indicate that the catalytic effect is due to an enzyme.

1965:
Biologists and biochemists have made outstanding progress within the past quarter century in elucidating principles and structures which govern the activities of living matter. |
These areas of progress include:
            A. The structure and code of the DNA molecule
            B. The use of radioactive isotopes as tracers in biological processes
            C. The citric acid cycle and its relationship to mitochondria
            D. The use of electron microscopy in revealing the structure of the cell
Discuss any one of these developments and its impact on biological thought and progress.
Your answer should include:
            a.  a brief account of the development
            b.  the names of the most prominent investigators involved
            c.  the nature of its impact on biology