NOTE: I have added some comments and explanations for some of the questions. These are in boldface. The two exams, by the way, differed primarily in the order of the questions, although a few questions were reworded or changed between exams.
It is possible to "fool" an organism by giving it a
molecule that "looks like", but isn't, something that
it needs. (Such a molecule is technically called an analog.)
Obviously, if a cell tries to use something that isn't really
what it's supposed to be, that cell's chemical reactions may be
blocked, its life functions will be seriously disrupted, and that
cell may die. Many drugs, poisons, and herbicides work this way.
1. The herbicide RoundupTM has this molecular structure:
Which class of organic molecules is RoundupTM most
like?
A. nucleic acids
B. carbohydrates
C. lipids
D. proteins
E. amino acids
[Notice that it has a carboxyl group, an R-group (just a hydrogen
atom, in this case) and an amino group that's had a big ugly carbon-phosphate
group stuck on it!]
2. The pesticide Rotenone has this molecular structure:
Which class of organic molecules is Rotenone most like?
A. nucleic acids
B. carbohydrates
C. lipids
[Think "steroids", which have similar multiple-ring structures]
D. proteins
E. amino acids
3. The AIDS drug AZT (a.k.a. zidovudine) has this molecular structure:
Which class of organic molecules is AZT most like?
A. nucleic acids
[It's a modified sugar stuck to a nitrogen-containing base.]
B. carbohydrates
C. lipids
D. proteins
E. amino acids
4. Which of the following molecules do NOT function in energy
storage?
A. starches
B. lipids
C. nucleic acids
D. ATP
E. All of these function in energy storage
5. Carbon atoms can exist as one of three isotopes, called 12C,
13C, and 14C. What is the difference between
these isotopes?
A. different numbers of protons
B. different numbers of electrons
C. different numbers of covalent bonds
D. different numbers of neutrons
E. different numbers of hydrogen bonds
6. A molecule with a polar "head" and two nonpolar "tails"
is likely to be
A. an enzyme
B. a protein
C. a steroid
D. a phospholipid
E. a triglyceride
7. A weak bond between oppositely charged parts of molecules,
in which electrons are not gained or lost, is a/an
A. hydrogen bond
B. covalent bond
C. ionic bond
D. hydrolytic bond
E. savings bond
8. The stage of photosynthesis in which carbon dioxide is taken
up and incorporated into more complex molecules is
A. the Krebs cycle
B. the light-dependent reactions
C. the Harley cycle
D. glycolysis
E. the Calvin cycle
9. Molecules that readily form hydrogen bonds with water are said
to be:
A. allosteric
B. hydrophobic
C. esoteric
D. lipophilic
E. hydrophilic
10. Which of the following requires a cell to expend energy?
A. facilitated diffusion
B. endocytosis
C. simple diffusion
D. osmosis
E. cirrhosis
11. The antibiotic penicillin works by blocking the active site
of an enzyme, transpeptidase, that certain bacteria use in forming
their cell walls. This is
A. competitive inhibition
B. feedback inhibition
C. allosteric regulation
D. facilitated regulation
E. fermentation
12. Photosynthesis involves a molecule called NADPH. Respiration
involves similar molecules called NADH and FADH2. Why
are these molecules necessary?
A. They store energy.
B. They make chemical reactions happen without being used
up themselves.
C. They carry electrons.
D. They pump protons across a membrane.
E. They can be fermented into lactic acid or ethanol.
13. Which of the following is a polymer of monosaccharides?
A. cellulose
B. DNA
C. ATP
D. ATP synthase
E. keratin
This is a drawing of a eukaryotic cell. There are eight labeled
parts, numbered (logically enough) 1 through 8. Questions 14
through 22 refer to this drawing.
14. Part 8 is a ribosome. What important function does
a ribosome carry out?
A. lipid synthesis
B. protein synthesis
C. ATP synthesis
D. cellular digestion
E. recognition
15. Part 7 is the external plasma membrane. What proteins
would you expect to find in the plasma membrane?
A. recognition proteins
B. transport proteins
C. receptor proteins
D. A, B, and C
E. A and C, but not B
16. Part 5 is a centriole or basal body. It functions
as an organizing center for the cell's cytoskeleton. Which of
the following best describes the cytoskeleton's function?
A. maintains the cell's shape
B. allows the cell to receive chemical signals
C. allows the cell to move
D. A, B, and C
E. A and C
17. Near the arrow labeled #7, you can see the cell taking in
large particles. What's the general term for this?
A. osmosis
B. passive transport
C. endocytosis
D. facilitated diffusion
E. cyclosis
18. One of these parts is the "packaging" center for
the cell. Which?
A. #1, the Golgi body
B. #4, the mitochondrion
C. #6, the Golgi body
D. #5, the centrioles
E. #2, the smooth endoplasmic reticulum
19. Which of the labeled structures would also be found in a prokaryotic
cell?
A. #1, the mitochondrion
B. #3, the nucleus
C. #4, the nucleolus
D. #7, the plasma membrane
E. #4, the chloroplast
20. The five following structures are not labeled in the diagram,
but four of them could be present in at least some eukaryotic
cells. Which one is not present in eukaryotes?
A. chloroplasts
B. cell wall
C. cytoskeleton
D. circular DNA
E. chromosomes
21. If you dunked the cell shown above into pure water, what would
happen?
A. Water would enter the cell by endocytosis.
B. Water would leave the cell by osmosis.
C. Water would enter the cell by facilitated diffusion.
D. Water would leave the cell by active transport.
E. Nothing would happen.
[ERROR -- None of the answers is correct. What would actually
happen is that water would enter the cell by osmosis. Free point
for all. You're welcome.]
22. The organ in your body called the pancreas produces
digestive enzymes, as well as important proteins such as insulin.
If this cell were a pancreatic cell, which of its parts would
you expect to be very large and/or numerous?
A. 1 and 8
B. 2 and 6
C. 1, 6, and 7
D. 3, 4, and 8
E. 3 only
In a desperate attempt to maintain your GPA, you decide to poison
your biology professor. An acquaintance gives you some cyanide
to slip into his coffee. She explains that cyanide denatures the
proteins in the electron transport chain.
23. What does cyanide do to the proteins in the electron transport
chain?
A. breaks the bonds between amino acids
B. clumps the proteins together
C. disrupts the bonds between R-groups
[That's what 'denature' means, right?]
D. plugs up the pores in them that let electrons cross
the membrane
[Electrons don't cross the membrane. Tricky, tricky, tricky.]
E. nothing at all; your accomplice is an idiot
24. What can a cell no longer do if its electron transport chain
is disrupted?
A. make ATP
B. make proteins
C. make ATP by glycolysis
D. make ATP by chemiosmosis
E. make lipids
25. Where do the electron transport proteins get electrons in
the first place?
A. ATP
B. water
C. the NAPA auto parts store on Harkrider, next to the
BondoTM
D. oxygen
E. NADH and FADH2.
26. Where, within the cells, would the cyanide have to go in order
to disrupt the electron transport chain?
A. the mitochondria
B. the chloroplasts
C. the nucleus
D. the endoplasmic reticulum
E. the muscles
27. Cyanide has the formula H-C_N.
[There's a triple bar between the C and the N, which may or
may not show up on your Web browser.] The triple bar in this
formula means that
A. the carbon atom and nitrogen atom share three pairs of
electrons
B. the carbon atom and nitrogen atom have the same number
of protons
C. the carbon atom and nitrogen atom have the same number
of neutrons
D. the carbon atom and nitrogen atom are bound together
with an ionic bond
E. the carbon atom and nitrogen atom share three electrons
28. Cyanide is a polar molecule. This means that it:
A. will not dissolve in water
B. will dissolve in water
C. smells like bitter almonds
D. will dissolve in oils or fatty acids
E. is found at the South Pole
29. Is it possible, at least, that cyanide would stop photosynthesis
as well?
A. Yes, because cyanide absorbs light
B. No, because plants don't have mitochondria
C. Yes, because photosynthesis uses electron transport proteins
D. No, because plants use different enzymes
E. No, because plants don't use electron transport proteins
30. The protein known as albumin (found in egg whites) is made
up of four identical polypeptides held together by hydrogen bonds.
This is an example of
A. primary structure
B. secondary structure
C. tertiary structure
D. quaternary structure
E. none of the above
31. The protein known as collagen I (found in your tendons) has
a helical shape, locked together by hydrogen bonds between amino
and carboxyl groups. This is an example of
A. primary structure
B. secondary structure
C. tertiary structure
D. quaternary structure
E. none of the above
32. The protein known as lysozyme (found in your tears) consists
of 129 amino acids: lysine-valine-phenylalanine-glycine-. . .-cysteine-arginine-leucine.
This is an example of
A. primary structure
B. secondary structure
C. tertiary structure
D. quaternary structure
E. none of the above
For these next ten questions, the E answer was always taken from the old Schoolhouse Rock educational short cartoons that ABC used to show on Saturday mornings. E was never the intended right answer, but in one case (#38) I will have to accept it. !?#*?*!?!
33. When an enzyme's activity is blocked by the very molecule
it helps to create, it is:
A. allosteric regulation
B. competitive inhibition
C. natural selection
D. feedback regulation
E. interjections-show excitement or emotion
34. A statement about how some aspect of the world works, that
has been tested several times and not been falsified, is a
A. hypothesis
B. control experiment
C. theory
D. guess
E. verb-that's what's happenin'
35. The First Law of Thermodynamics states that
A. energy cannot be created or destroyed
B. the number of electrons in an atom must equal the number
of protons
C. E=mc2
D. atoms are stable when they have filled outer orbitals
E. a noun's a person, place or thing
36. A polymer of amino acids is held together by
A. ionic bonds
B. hydrogen bonds
C. peptide bonds
D. amphipathic bonds
E. hookin' up words an' phrases an' clauses
37. The enzyme amylase, found in your saliva, breaks down starch
into
A. amino acids
B. sugars
C. nucleotides
D. fatty acids
E. a circle that turns 'round upon itself
38. Prokaryotic cells have all of the following EXCEPT:
A. cell wall
B. ribosomes
C. mitochondria
D. cytoplasm
E. Naughty Number Nine
[C was the intended right answer. I later realized that E is
also right, though I certainly didn't intend that. . .]
39. A eukaryote's ribosomes are made in the:
A. nucleolus
B. cytoskeleton
C. cytoplasm
D. Golgi complex
E. three-ring government
40. A eukaryote's smooth endoplasmic reticulum (ER) is where what
gets made?
A. lipids and carbohydrates
B. nucleic acids
C. proteins
D. organelles
E. just a Bill
41. If there's not enough oxygen, your muscle cells may convert
pyruvate and NADH to lactic acid and NAD+. This process
is
A. the Krebs cycle
B. feedback regulation
C. covalent bonding
D. fermentation
E. sufferin' till suffrage
42. Simple diffusion of water across a plasma membrane is called:
A. psychosis
B. scoliosis
C. osmosis
D. neurosis
E. Rufus Xavier Sarsaparilla
For the last eight questions, answer:
A if the statement is a testable hypothesis;
B if it is an untestable statement.
43. The speed of light is, like, pretty fast.
B [vague statements can't usually be tested -- what does 'pretty
fast' mean here, anyway?]
44. Captured UFOs are being kept in a warehouse on the outskirts
of Roswell, New Mexico.
A [you could test it by going to Roswell and looking in every
warehouse]
45. The Union Army captured the Confederate outpost of Fort Hindman,
on the Arkansas River near the town of Gillett, on January 10,
1863.
A [you could test it by going to the site and looking for artifacts,
by reading memoirs and letters and eyewitness accounts, etc.]
46. The sun, moon, and all planets and stars revolve around the
earth, which is flat and fixed at the center of the universe.
A [you could test it, say, by going up in a spaceship and having
a look]
47. Alien beings are sending messages to Earth by spiritual psychic
waves that can only be picked up by LaToya Jackson.
B [untestable -- seems pretty obvious to me]
48. Charles Ives's Symphony #2 is more beautiful than John
Cage's 4'33".
B [aesthetic judgments aren't testable]
49. God created the Heavens and the Earth at exactly 9:53 this
morning, September 21, 1998. Every memory you have of anything
that happened earlier than 9:53 AM, and all physical evidence
of anything that might have happened before 9:53 AM, was planted
by the Devil.
B [seems pretty obvious!]
50. Human life begins at conception because that's when the soul
enters the body.
B [how would you test for the presence or absence of a soul?]