Name:____________________________
Fall Semester, 2004
Exam I
I. Multiple choice (80 points)
1. Which of these terms refers to the process of maintaining relatively constant internal
conditions in a living organism?
a. Order.
b. Sensitivity
c. Development
d. Homeostasis
e. Regulation
2. The cation form of an element is compared to the uncharged form of the same element.
Which of the following statements is TRUE?
a. The cation has less protons.
b. The cation has a different half-life
c. The cation has more neutrons.
d. The cation has less electrons.
e. The cation has more electrons.
3. Mitochondria are believed to have evolved from:
a. the golgi apparatus.
b. the endoplasmic reticulum.
c. invaginations of the plasma membrane
d. endosymbiont bacteria.
e. early photosynthetic organisms.
4. A solution with neutral pH would have a pH value of:
a. 0.0
b. 1.0
c. 7.0
d. 10.0
e. 14.0
5. A substance which acts to maintain the pH of a solution at its present value, counteracting
the effects of adding acid or base, is called a/an:
a. anion.
b. cation.
c. buffer.
d. salt.
e. hydrophile.
6. Two atoms share 2 electrons. This is an example of:
a. a single bond.
b. a double bond.
c. a triple bond.
d. a hydrogen bond.
e. None of the above is a correct answer.
7. Which of the following will increase the rate of a chemical reaction?
a. Higher temperature
b. Higher reactant concentration
c. A catalyst
d. All of the above speeds up a chemical reaction.
e. None of the above speeds up a chemical reaction.
8. Water is a liquid at room temperature (and not a gas) because:
a. it can form ionic bonds between ionized molecules.
b. it can form hydrogen bonds between individual molecules.
c. it can dissociate to form hydrogen and hydroxide ions.
d. it has a relatively high molecular weight compared to gases.
e. it forms a strong hydration shell.
9. A crystal of sodium chloride is held together by:
a. hydrogen bonds.
b. ionic bonds.
c. covalent bonds.
d. hydration shells of the individual molecule.
e. a chemical reaction between the sodium and chloride ions.
10. Which of the above properties of water was/is not important to the development of living
systems?
a. Cohesion—water molecules “stick together”
b. High specific heat--water requires much energy to raise its temperature
c. High heat of vaporization--much energy absorbed when water evaporates
d. Low density of ice—it floats
e. All of the above are properties of water that are important to the development and
maintenance of life on this planet.
11. The basic monomeric repeat unit which is used to assemble nucleic acids is the:
a. amino acid
b. sugar
c. lipid
d. nucleotide
e. phosphate
12. An example of a structural polymer made entirely of glucose repeat units is/are:
a. The cell membrane.
b. Microtubules.
c. The nuclear membrane.
d. A ribosome.
e. None of the above answers is/are correct.
13. The type of reaction commonly used to disconnect (break apart) the monomeric units of
macromolecules is best classified as a/an:
a. exergonic reaction.
b. hydrolysis reaction.
c. disulfide reaction.
d. hydrogen bonding.
e. dehydration reaction.
14. The actual sequence of amino acids in a polypeptide/protein is called its:
a. primary structure.
b. secondary structure.
c. tertiary structure.
d. quaternary structure.
e. None of the above are correct answers.
15. An example of a type of chemical bond which involves a full separation of charge
(transfer of electrons) is a/an:
a. hydrogen bond.
b. ionic bond.
c. covalent bond.
d. hydrophobic bond.
e. electron bond.
16. A storage fat molecule is made up of:
a. two fatty acids, glycerol, phosphate and another alcohol type unit.
b. three fatty acids and glycerol.
c. two fatty acids and glycerol.
d. two fatty acids, glycerol and a phosphate group.
e. three fatty acids, glycerol, phosphate and an alcohol type unit.
17. The transport of glucose from the plasma into a human red blood cell is accomplished by:
a. active transport.
b. cotransport.
c. diffusion.
d. facilitated diffusion.
e. pinocytosis.
18. The four most common elements in living systems are:
a. carbon, hydrogen, oxygen and phosphorous.
b. carbon, hydrogen, nitrogen and oxygen.
c. carbon, oxygen, nitrogen and phosphorous.
d. carbon, oxygen, nitrogen and iron.
e. carbon, oxygen, nitrogen and calcium.
19. The beta-sheet and alpha-helix of a folded protein/polypeptide would be examples of its:
a.
b.
c.
d.
e.
primary structure.
secondary structure.
tertiary structure.
quaternary structure.
All of the above are correct answers.
20. An example of a storage carbohydrate common in plants is:
a. cellulose.
b. glycogen.
c. starch.
d. chitin.
e. choline.
21. The atomic number of an element refers to the:
a. number of protons in the nucleus.
b. number of protons plus neutrons in the nucleus.
c. number of neutrons in the nucleus.
d. number of electrons in the outer shell/orbital.
e. number of covalent bonds it routinely makes with other atoms.
22. (CH2O)n is the common formula for:
a. amino acids.
b. sugars.
c. fatty acids.
d. hydrophylic molecules.
e. hydrophobic molecules.
23. The charged particle with a mass of approximately 1 in the nuclei of atoms is called a/an:
a. neutron
b. proton
c. nucleus
d. electron
e. neutrino
24. Biological membranes are composed of [choose the best answer]:
a. fats.
b. a peptidoglycan layer.
c. a phospholipid bilayer.
d. Carbohydrate fibers related to cellulose.
e. All of the above are correct answers.
25. Ribose is an example of a/an:
a. purine.
b. pyrimidine.
c. sugar.
d. aldehyde.
e. fat.
26. Which of the following is a nucleotide?
a. ATP
b. A fat
c. A sugar
d. A phospholipid
e. Cholesterol
27. The monomer repeat units of a protein are connected to each other by what type of
bonds?
a. Peptide bonds
b. Phosphodiester bonds
c. Ester bonds
d. Hydrogen bonds
e. Ionic bonds
28. What is the defining characteristic of an acid?
a. It donates hydrogen ions.
b. It has an excess of hydroxide ions
c. It accepts hydrogen ions.
d. it has a pH greater than 7.
e. It will donate or accept hydrogen ions depending on the pH.
29. If two atoms share a pair of electrons, they are held together by a(n)
a. polar bond
b. hydrogen bond
c. neutral bond
d. covalent bond
e. ionic bond
30. Which of the following is a CORRECT statement about the scientific method?
a. it distinguishes between good and bad
b. it can only be done by someone with a Ph.D. or advanced training
c. it organizes evidence and helps us predict what will happen in our environment
d. it requires expensive laboratory equipment
e. its methods are substantially different from the way people normally process information
31. Based upon your knowledge of atomic structure, an atom with 14 protons in its nucleus
a. would be very stable and unreactive
b. would be very positively charged
c. tend to form covalent bonds
d. would probably form ionic bonds
e. none of the above
32. Each amino acid differs from others in the
a. location of the carbon atoms
b. nature of the R group
c. number of carboxyl groups
d. all of the above
e. size of the amino group
33. The bonds between two carbon atoms or carbon and hydrogen represents
a. shared electrons
b. energy sinkholes
c. both a and d
d. slurpy factoids
e. ionic bonds
34. Which of the following lists the four elements that make up 97% of all living tissue?
a. hydrogen, carbon, nitrogen, oxygen
b. carbon, hydrogen, nitrogen, sulfur
c. oxygen, carbon, helium, nitrogen
d. nitrogen, carbon, helium, sulfur
e. oxygen, nitrogen, carbon, sulfur
35. Pure water has a pH of 7 because it contains
a. equal numbers of hydrogen and hydroxide ions
b. none of the above
c. equal numbers of hydrogen and oxygen atoms
d. a, b, and c are correct
e. a variety of buffers
36. You drink a glass of lemonade, but your body's pH does not change. This is an example of how
organisms:
a. maintain homeostasis.
b. are immune to acid
c. maintain organization
d. are what they eat.
e. adapt to their environment.
_______________________________________________________________________
Match the following names to the proper functional group
a.
-OH
d.
-C=O
b.
-SH
e.
-NH3
c.
-PO4
37. A sulfhydryl group
38. An amino group
39. A carbonyl group
40. A hydroxyl group
_______________________________________________________________________
II. (10 points) Fill in the blanks with the correct word or statement. The value of each question is in
the parentheses following the number.
1. (1) The linear arrangement of amino acids in the polypeptide chain is referred to as the
__________________ structure of the protein.
2. (1) Cholesterol, testosterone, and estrogen are all examples of _______________________________.
3. (2) List two of the attributes something must have to be considered truly alive:
__________________________________ and
__________________________________________________.
4. (1) A compound that maintains a solution at a constant pH by accepting or releasing H+ in response to
small changes in H+ concentrations is known as a __________________________.
5. (1) pH is the measure of the concentration of ________________________ present in a solution.
7. (1) Name one function of carbohydrates _______________________________________________
8. (1) Water is attracted to any substance which is _______________________________________
9. (1) Name one function of nucleic acids ________________________________________
10. (1) The 3 parts of a nucleotide are a nitrogen, a phosphate group and a __________________
III. (5 points) Matching. Place the letter of the correct answer into the blank to the left of the term.
_____1. glucose
_____2. steroid
_____3. hydroxyl group
(B)
(A)
_____4. phospholipid
_____5. amino acid
(C)
(D)
(E)
(F)
-OH
(G)
-COOH
(H)
-NH2
IV. (5 pts). Label the parts of the microscope