BIOLOGY 1400
Fall 1998
Lecture Exam 1-A
KEY

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.


For the first eight questions, answer:

A if the statement is a testable hypothesis;

B if it is an untestable statement.

1. The speed of light is, like, pretty fast.
B--this is too vague to be testable

2. Human life begins at conception because that's when the soul enters the body.
B--untestable (how would you test for the presence of a soul?)

3. UFOs exist, but they are made of a mysterious spiritual form of matter, which cannot be photographed or measured with any known instruments.
B--untestable

4. Alien beings are sending radio messages to Earth.
A--you can test this, for example, by building a radio receiver and listening for messages

5. Michelangelo's David is more beautiful than Brancusi's Bird in Space.
B--aesthetic judgments aren't testable

6. 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--untestable (obviously!)

7. 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 this, for example, by building a spacecraft and looking for yourself

8. 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 this, for example, by going to the site and looking for artifacts, or by reading eyewitness accounts and memoirs

In a desperate bid 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.

9. 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
This is the definition of 'denature'!
D. plugs up the pores in them that let electrons cross the membrane
Electrons don't cross the membrane. Protons do. Tricky, tricky, tricky.
E. nothing at all; your accomplice is an idiot

10. 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

11. 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.

12. 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

13. Cyanide has the formula H-C_N. That should be a triple bar between the C and the N -- your computer may or may not be able to display it. 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

14. 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

15. 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

This is a drawing of a eukaryotic cell. There are eight labeled parts, numbered (logically enough) 1 through 8. Questions 16 through 24 refer to this drawing.


16. 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

17. 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

18. 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

19. 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

20. 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

21. 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

22. 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

23. 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 are correct. In fact, water would enter the cell by osmosis. Two free points for everyone. You're welcome.

24. 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
Golgi body and ribosomes
B. 2 and 6
C. 1, 6, and 7
D. 3, 4, and 8
E. 3 only

25. 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

26. 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

27. 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
This is, in fact, the definition of an isotope.
E. different numbers of hydrogen bonds

28. 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

29. 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

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
"Hydrogen bonds between amino and carboxyl groups" is secondary structure. It would be tertiary structure if they were between R-groups.
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

33. Which of the following requires a cell to expend energy?
A. facilitated diffusion
B. endocytosis
C. simple diffusion
D. osmosis
E. cirrhosis

34. 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.

35. 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

36. Molecules that readily form hydrogen bonds with water are said to be:
A. allosteric
B. hydrophobic
C. esoteric
D. lipophilic
E. hydrophilic

37. Which of the following is a polymer of monosaccharides?
A. cellulose
B. DNA
C. ATP
D. ATP synthase
E. keratinIt is possible to "fool" an organism by giving it a molecule that "looks like", but isn't, something that it needs. 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.

38. 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

39. 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

40. 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

For these last 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 (#46) I will have to accept it. !?#*?*!?!

41. 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

42. 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'

43. 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

44. 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

45. 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

46. Prokaryotic cells have all of the following EXCEPT:
A. cell wall
B. ribosomes
C. mitochondria
D. cytoplasm
E. Naughty Number Nine

47. A eukaryote's ribosomes are made in the:
A. nucleolus
B. cytoskeleton
C. cytoplasm
D. Golgi complex
E. three-ring government

48 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

49. 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

50. Simple diffusion of water across a plasma membrane is called:
A. psychosis
B. scoliosis
C. osmosis
D. neurosis
E. Rufus Xavier Sarsaparilla


View key to test version B | Return to syllabus