BIO 171  - First Exam  - 2015

Links go to pertinent passages of book


Multiple Choice. 

Place the letter of the choice that best answers the question on the line to the left.
Two Points Each. NOTE: “e” answers are never the correct answer.

_______ 1.  Which would be the main process of a digestive system?

                    a. Dehydration synthesis         b. Dynamic equilibrium        c. Carboxylation         d. Hydrolysis
                                    e. How come "digestion" isn't one of the choices?

_______ 2.  Chaperonins are involved in

                a. Enzyme regulation         b. Gene expression        c. Protein folding         d. Rate equilibrium
                                                                    e. Molecule proms

_______ 3.  Which commonly involve some sort of mineral or metal?

                a. Ligands and binding sites         b. Cofactors and prosthetic groups        c. Coenzymes and cofactors
                d. Ligands and prosthetic groups                            e. Nasty scraping sounds

_______ 4.  Plant starch and plant fiber are similar molecules but differ in

                a. Types of bond linkages         b. Amounts of Nitrogen         c. Amino acid order
                d. Amounts of Sulfur                             e. Yummy goodness

_______ 5.  Which would most likely not have much stereospecificity?

                a. Antibodies         b. Sense receptors         c. Enzymes        d. Codons
                         e. People who buy their components at Wal-Mart

_______ 6.  A base, by definition,

                a. Adds H+ to a solution, lowering pH         b. Removes H+ from a solution, lowering pH
                c. Adds OH- to a solution, raising pH         d. Removes OH- from a solution, raising pH
                        e. Wait! I know this! ...How come none of the answers refer to baseball -?

_______ 7.  Most cellular synthesis reactions are

                a. Enzyme-mediated         b. Coupled         c. Endergonic        d. All of the above         e. Very tiny

_______ 8.  The numbers of valence electrons in an atom are most closely associated with

                a. Its weight         b. Its chemical properties         c. Radioactivity         d. Its atomic number
                                                                        e. Its odor

_______ 9.  The "D" of DNA and the "R" of RNA are based upon which part of the molecule?

                a. Sugar         b. Amino Acid         c. Phosphate        d. Nitrogenous base         e. The diggelly-riggelly part

_______ 10.  The Michaelis Constant (km) is a measure of

                a. Reaction rate         b. Equilibrium point        c. Enzyme activity         d. Energy release
                                    e. If it’s constant, isn’t it always the same measurement?

_______ 11.  Which was most obviously hydrophobic?

                a. Sugar         b. Starch         c. Vegetable oil        d. Protein         e. Well, how obvious was it?

_______ 12.  Carbon dating doesn’t work past about 60,000 years because there is
                                        too little _______ to accurately measure

                a. Nonradioactive carbon         b. Radioactive carbon        c. Radioactivity         d. All of these
                                                                        e. Profile updating

_______ 13.  An R group is part of a(n)

                a. Amino acid         b. Starch         c. Nucleic acid        d. Mucopolysaccharide
                                    e. A bunch of people yelling, "Arrrgh!"

_______ 14.  Which is a domain?

                a. Allele         b. Coenzyme         c. Cofactor        d. Regulatory site         e.

_______ 15.  A hydrocarbon is said to be unsaturated if

                a. It has one or more double bonds between carbon atoms
                b. It contains more than one functional group
                c. Each internal carbon atom is covalently bonded to two hydrogen atoms
                d. One end of the molecule is hydrophilic while the other end is hydrophobic
                e. It isn't wet enough

_______ 16.  ATP often works through

                a. Electron transfer         b. Group transfer potential        c. Ionic activation         d. All of these
                                                                e. Intimidation and extortion

_______ 17.  Glucose and fructose are both C6H12O6, but their atoms are arranged differently,
                                        which makes them

                a. Polysaccharides         b. Disaccharides         c. Isomers         d. Soluble
                                                e. Something to avoid at all costs

_______ 18.  Tubulin in your food would be absorbed as

                a. Sugars             b. Starches            c. Nucleotides             d. Amino acids
                            e. There’s tubulin in my food? Is it making me rounder?

Short Answer.
Pick NINE questions to answer in the spaces provided.

NOTE: if you answer MORE than nine, only the first nine will be corrected.
Four Points each. Partial credit is possible.

1.  What is Dynamic Reaction Equilibrium?

2.  Put the simple hydrocarbons in order according to how many carbons they have.
1 2 3

3.  Give two fairly specific types of limiting factors in cellular reactions.


4.  What are two different types of the major organic polymers found in organisms?


5.  What are two different common biological roles played by irreversible inhibitors?


6.  What advantage do lipid-based hormones have on other types of hormones?

7.  Briefly explain why biologically-active molecules rarely if ever involve ionic bonds.

8.  What are two different things that can actually explain what “junk DNA” is?


9.  What is a Q10?

10. What are two ways that different isotopes of the same element differ?


11. Give two different examples of allosteric effects involving proteins.


12. What are the component parts of a lipid molecule? Include numbers (how many?) for each component.

13. What are two different types of indirect enzyme inhibition?


14. What is it specifically about pH that affects the workings of an enzyme (what does a change do to the enzyme itself)?

15. Give two distinct and different features that would be found in disaccharide synthase.


16.  Give two different circumstances under which a change in a codon leads to no change in the function of the coded protein.


17. On a curve showing the effects of temperature on enzyme activity, the rates drop off both above and below the optimum temperature. Explain why the rates drop -

Long Answer.

Select and answer completely any four of the following questions.
Note: if you answer more than four, only the first four will be corrected.
Seven Points Each. Partial credit is possible.

1.  Using the numbers of bonds as a guide, fill in the symbols for either Carbon, Hydrogen, Nitrogen, or Oxygen.
These are boxes or circles with bonds drawn between them.

2.  In the graph below of Michaelis-Menten Kinetics, explain why the curve is doing what it’s doing at each marked point, in terms of the enzyme molecules at work.

Can't get graph right - marked at upslope, curve near top, flat top.

3.  What are four classes of molecular function largely performed by proteins?



4.   Name and give a brief description for the four levels of protein structure.





5.  Briefly explain, in terms of density, the steps in the “turning over” and freezing process that local lakes go through in the late autumn.

6.   All for the most common isotope –




# 35

Column 7

How many


How many



ion form?

How many

electrons? (Radical form)

7.   For four functional organic molecule groups, give the name, then show the arrangement of atoms in enough detail to demonstrate completely how each group works.





Link to Answer Key

Answer as many or as few as you wish. You can't lose points on the rest of the exam by getting these wrong. Partial credit is possible.

Avogadro's Number is 6 X 1023. What is it a measure of?

Nuclear radiation varies in energy and penetration power due to what other features? Three Points.

What are the two reasons, for Three Points each, for why vegetable oil forms separate blobs or bubbles when mixed into water?

At most universities, which course is most likely to "weed out" the many premed students? Three Points.

The starches in foods are fairly easy to digest because they are constructed of easily-broken bonds. What advantage does that give to the plants that make the starch? Three Points.

What is it about high-fiber food that makes it an effective stool softener? Address molecule-level issues, for Three Points.

Why exactly is Sulfur an important component of many proteins? Three Points.

What are two "unusual" aspects of the amino acids found in living things, features that have to be addressed when explaining the origins of Life's chemistry? Three Points each.

Why is it not reasonable that an enzyme would catalyze a reaction equally in both directions? Three Points.

What might be the advantage of not lowering a low-grade fever that has resulted from a bacterial infection? Be specific. Three Points.


BIO 171

Michael McDarby


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