Biology 202 Sample Exam                                                                                                                      Name: _________________________ 

The intention to this sample exam is to give you a sense of the kind of questions you might see on a typical exam. Your actual exam may have more and certainly different questions than you see here, especially depending on the block of material we are covering. Typically, I try to have about half of the total points on the exams be on multiple-choice questions and about half on discussion and short answer.  

Directions: Read each of the following questions carefully and select the most appropriate answer. Feel free to ask for clarification if the question in unclear (2 points each out of a possible 100 points). 

1.         The oxidation of glucose into two molecules each of pyruvic acid, ATP, and NADH is called :

A.         oxidation of pyruvic acid.

B.         fermentation.

C.         the Krebs cycle.

D.         glycolysis. 

2.         A solution with a pH of 5:

A.         is basic.

B.         is more acidic than a solution with pH of 4.

C.         has a hydroxide ion concentraiton 100 times more than a solution of pH 6.

D.         has a hydroxyl ion concentration of 10^‑5 molar. 

3.         In the following reaction what are the substrates and products, respectively?

                                                                        peroxidase

guaiacol + hydrogen peroxide ‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑‑> tetraguaiacol + water 

A.         guaiacol and tetraguaiacol; hydrogen peroxide and water

B.         guaiacol and hydrogen peroxide; tetraguaiacol and water

C.         tetraguaiacol and water; guaiacol and hydrogen peroxide

D.         guaiacol, hydrogen peroxide and peroxidase; tetraguaiacol and water 

4.         A biochemist is studying the transport of compound X into cells. She finds that transport slows down when the cells are poisoned with a protein inhibitor, but that the rate of transport is unaffected by a chemical that inhibits energy production. Under normal circumstances compound X is probably transported into the cell by:

A.         simple diffusion.

B.         osmosis.

C.         facilitated diffusion.

D.         active transport. 

5.         The final electron acceptor of the electron transport system is:

A.         CO₂.

B.         H₂O.

C.         O₂.

D.         NADP+. 

6.         In the metabolic pathway shown below, product Z is an allosteric inhibitor of enzyme E2. Product Z can therefore first inhibit the production of:

                                                E1            E2           E3            E4

                                          V ‑‑‑‑‑‑‑‑> W ‑‑‑‑‑‑‑‑> X ‑‑‑‑‑‑‑‑> Y ‑‑‑‑‑‑‑‑> Z

A.         V

B.         W

C.         X

D.         Y

7.         Oxidation and reduction reactions are important in which of the following metabolic pathways?

A.         respiratory electron transport system (ETS)

B.         glycolysis

C.         Krebs cycle

D.         all of the above 

8.         According to the second law of thermodynamics:

A.         the potential energy of the initial state of the system is always less than the potential energy of the final state.

B.         potential energy increases and entropy increases.

C.         kinetic energy is continually converted to potential energy.

D.         potential energy decreases and entropy increases. 

9.         5 mm is equal to:

A.         0.5 nm.

B.         50 nm.

C.         500 um.

D.         5000 um. 

10.        Enzymes increase the rate of a biochemical reaction by:

A.         lowering the activation energy.

B.         increasing the temperature of the substrate.

C.         transferring kinetic energy to the substrate.

D.         by decreasing the effective concentration of the substrates. 

11.        What information about an enzyme can be determined using Michaelis‑Menten kinetics?

A.         The number of active sites on an enzyme.

B.         The optimum temperature for an enzyme.

C.         The maximum velocity at a given temperature of an enzyme.

D.         The Km or the affinity of an enzyme for its substrate. 

12.        Hydrophobic substances are ______, whereas hydrophilic substances are:     .

A.         water‑loving; water‑fearing

B.         polar; non‑polar

C.         soluble in water; soluble in lipid

D.         non-polar, water-loving 

13.        A molecule with the chemical formula C₆₀H₁₂₀O₆₀ is probably a(n)

A.         carbohydrate

B.         amino acid.

C.         nucleotide.

D.         protein.

14.        Which of the following organelles contains its own DNA and is able to synthesize some of its own protein?

A.         endoplasmic reticulum

B.         mitochondria

C.         ribosomes

D.         none of the above 

15.        Catabolic reactions are generally ___________, while anabolic reactions __________ .

A.         are exergonic; are endergonic

B.         are chemical reductions; are chemical oxidations

C.         increase enthalpy (or heat content); increase entropy

D.         all of the above 

16.        The structure of a protein depends on several different types of chemical bonds and group interactions. Which of the following are necessary to stabilize the secondary structure of a protein?

A.         peptide bonds

B.         hydrogen bonds between side groups of the amino acids residues

C.         disulfide bonds

D.         ionic bonds 

17.        The part of the protein that extends through the center of the lipid bilayer is composed of amino acids that are:

A.         hydrophobic

B.         water soluble.

C.         positively charged.

D.         negatively charged. 

18.        Polymerization reactions in which proteins are synthesized from amino acids or polysaccharides are synthesized from monosaccharides

A.         result in the formation of water.

B.         are condensation reactions.

C.         require the input of energy.

D.         result in the formation of covalent bonds between monomers

E.         all of the above. 

19.        Which of the following statements is true of all cations?

A.         The atom has more protons than electrons.

B.         The atom has more electrons than protons.

C.         The atom has fewer neutrons than protons.

D.         The atom has more protons than does a neutral atom of the same element. 

20.        When a red blood cell is placed in a solution of pure water, the interior of the cell is best described as being:

A.         isotonic.

B.         hypertonic.

C.         hypotonic.

D.         none of the above, you cannot tell from the information given

Briefly define or describe the following terms or concepts (2 points each).            

 21.    Osmosis

22.     Cotransport

23.    Hydrogen Bond

24.     Allosteric Enzyme

25.     Phospholipid

 

Discussion, you will typically have 2-3 discussion questions that give you an opportunity to demonstrate your understanding of a more complex process. These questions are typically worth 15-20 points out of a possible 100 points.  

Directions: Answer the question asked as completely as possible in the time provided. Please ask for clarification if the question is unclear. 

26.        There are a number of major themes that are used to explain how cells can function. These include the activity and organization of Nucleic Acids, Proteins and Biological Membranes. Lets explore the last of these three. Why are biological membranes important to the life of cells? What is the molecular structure of cell membranes as described by the fluid mosaic model?

27.        We discussed four major classes of biological macromolecules. Lets look at two of these groups by comparing and contrasting the molecular structure of a protein and a lipid (triglyceride or phospholipid).                              

28.        There are a number of ways cells can obtain energy to maintain order. One series of pathways involves the catabolism of glucose. Discuss the process of glycolysis, include the steps of the pathway, where it occurs in the cell and what kinds of cells use this pathway.

 

 Sometimes I will include an extra credit question that typically is worth 5 points out of a possible 100 points on a given exam, here is a typical question.

Extra Credit: Discuss the role of ATP Synthetase in chemiosmosis.