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BY 123 Raut – Mock Exam Unit I
09/21/14
1. Which of the following orders represents the hierarchy of biological organization from the most to the least complex level?
A) organelle, cell, organ system, population, community, ecosystem
B) ecosystem, community, organism, tissue, cell, organelle
C) biosphere, population, organism, cell, tissue, molecule
D) biosphere, community, tissue, organ system, molecule, organelle
E) organism, population, organ system, tissue, molecule, cell
2. What theme is BEST exemplified by a dog using a treat biscuit in order to power his jumping around to catch birds in the backyard?
A) feedback mechanisms regulate biological systems
B) organisms interact with other organisms and the physical environment
C) life requires energy transfer and transformation
D) A and C
E) B and C
3. Which theme does not belong?
A) emergent properties
B) structure and function
C) growth and development
D) evolution
E) the continuity of life is based on heritable information in the form of DNA
4. Which does not belong in the classification?
A) Bacteria
B) Archaea
C) Eukarya
D) Animalia
5. You find a unicellular organism in your fingernail that interests you. After analysis and several tests, you see that it possesses a nucleus and a chloroplast. What classification can you give it?
A) protist
B) animal
C) plant
D) fungi
E) archaea
6. Several mishaps have been bothering Jesse and Walter lately; they want to experiment if the stunted growth of the plants they have planted has anything to do with the plants’ being in a chemical lab. What would be a good control for their experiment?
A) plants in the chemical lab
B) plants that are grown outside only in contact with fresh air

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C) plants that receive more water everyday
D) plants that have more soil in their pots
E) a new laboratory
7. T/ F Trace elements are not essential and are relatively small in size.
8. Phosphorus-31 is an isotope of phosphorus. Given that phosphorus has an atomic number of 15, what is proper number of protons, neutrons, and electrons on this atom?
A) 15, 15, 16
B) 16, 15, 16
C) 15, 14, 17
D) 15, 16, 15
E) 14, 17, 15
9. What is not a fact about isotopes?
A) they are different atomic forms of the same element
B) they can act as tracers, following atoms through metabolism
C) isotopes differ in their numbers of neutrons amongst the same elements
D) isotopes are usually positively or negatively charged
E) isotopes can become radioactive or can give off particles and energy spontaneously
10. Electrons exist only at fixed levels of potential energy. However, if an atom absorbs sufficient energy, a possible result is that
A) an electron may move to an electron shell farther out from the nucleus.
B) an electron may move to an electron shell closer to the nucleus.
C) the atom may become a radioactive isotope.
D) the atom would become a positively charged ion, or cation.
E) the atom would become a negatively charged ion, or anion.
11. Nitrogen (N) is much more electronegative than hydrogen (H). Which of the following statements is correct about the atoms in ammonia (NH
3
)?
A) Each hydrogen atom has a partial positive charge .
B) The nitrogen atom has a strong positive charge.
C) Each hydrogen atom has a slight negative charge.
D) The nitrogen atom has a partial positive charge.
E) There are covalent bonds between the hydrogen atoms.
12. Which of these terms is NOT as closely related to the others?
A) ionic bond
B) molecule
C) cation
D) anion
E) salts
13. Which of the following is not considered to be a weak molecular interaction?
A) a covalent bond

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B) a van der Waals interaction
C) an ionic bond in the presence of water
D) a hydrogen bond
E) A and B only
14. One of the buffers that contribute to pH stability in human blood is carbonic acid
(H
2
CO
3
). Carbonic acid is a weak acid that dissociates into a bicarbonate ion (HCO
3-
) and a hydrogen ion (H + ). Thus,
H
2
CO
3
⇔ HCO
3-
+ H +
If the pH of the blood drops, one would expect
A) a decrease in the concentration of H
2
CO
3
and an increase in the concentration of HCO
3-
.
B) the concentration of hydroxide ion (OH ) to increase.
C) the concentration of bicarbonate ion (HCO
3-
) to increase.
D) the HCO
3-
to act as a base and remove excess H + with the formation of H
2
CO
3
.
E) the HCO
3-
to act as an acid and remove excess H + with the formation of H
2
CO
3
.
15. If the pH of a solution is increased from pH 5 to pH 7, it means that the
A) concentration of H + is 2 times greater than what it was at pH 5.
B) concentration of H + is 2 times less than what it was at pH 5.
C) concentration of OH is 100 times greater than what it was at pH 5.
D) concentration of OH is 100 times less than what it was at pH 5.
E) concentration of H + is 100 times greater and the concentration of OH is 100 times less than what they were at pH 5.
16. Which of the following is NOT a result of hydrogen bonding?
A) connection of double helices
B) cohesion of water
C) moderation of temperature by water
D) floating of ice on water
E) solvent of life
F) secondary structure of a protein
G) none of the above
17. How many grams of sucrose (table sugar) would one need to make 1.5 L of a 1 M solution of the molecule? (MW of sucrose = 342.3 g/mol)
A) 342.3
B) 1.5
C) 513.4
D) 684.6
E) 228.2
18. Why are steam burns so severe?
A) heat is released when steam condenses into liquid (FORMATION OF HYDROGEN BONDS
RELEASES HEAT)

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B) heat is absorbed when steam condenses in liquid
C) release of heat by breaking of hydrogen bonds
D) a change in density when it condenses to form a liquid
E) high surface tension
19. What can contribute to a raft spider being able to “glide” on top of water?
A) hydrogen bonds
B) high surface tension
C) hydrophobic coating of the legs
D) A and B only
E) all of the above
20. Why do bottles of soda and beer seem to explode in the freezer?
A) carbonation exceeds limited space
B) water forms crystalline structure
C) water expands as its hydrogen bonds space out and solidify
D) B and C only
E) all of the above
21. The concept of vitalism is based on a belief in a life force outside the jurisdiction of physical and chemical laws. According to this belief, organic compounds can arise only within living organisms. Which of the following did the most to refute the concept of vitalism?
A) Wöhler's synthesis of urea
B) Berzelius's distinction between organic and inorganic compounds
C) Miller's experiments with ancient atmospheres
D) Rodriguez's studies of phytochemicals
E) Kolbe's synthesis of acetic acid
22. Examine glucose and fructose. Both have molecular formulas of C
6
H
12
O
6
.
These two molecules are
A) geometric iosotopes.
B) enantiomers.
C) cis-trans isomers.
D) structural isomers.
E) nonisotopic isomers.

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23. Jesse argues that testosterone and estradiol have to be the same since they look the same. Walter argues that there are little properties and functional groups that make them different. Why’s Walter right?
A) structure fits function
B) they are enantiomers; one is effective and one is ineffective
C) functional groups give molecules distinction
D) A and C only
E) all of the above
24. What happens when ATP reacts with water and loses a phosphate?
A) ADP is formed.
B) AMP is formed.
C) energy is released.
D) A and C only.
E) all of the above
25. A compound contains hydroxyl groups as its predominant functional group. Which of the following statements is true concerning this compound?
A) It lacks an asymmetric carbon, and it is probably a fat or lipid.
B) It should dissolve in water.
C) It should dissolve in a nonpolar solvent.
D) It won't form hydrogen bonds with water.
E) It is hydrophobic.
26. A carbon skeleton is covalently bonded to both an amino group and a carboxyl group.
When placed in water it
A) would function only as an acid because of the carboxyl group.
B) would function only as a base because of the amino group.
C) would function as neither an acid nor a base.
D) would function as both an acid and a base.
E) is impossible to determine how it would function.
27. After he worked out, Aaron finished his meal at KFC where he ate a bucket of chicken.
How will this protein turn into his muscles starting with its breakdown? (which steps will happen)
A) hydrolysis in the stomach and intestines
B) reabsorption through microvilli into the bloodstream
C) dehydration reactions in the muscles to make polypeptide polymers
D) A and C only
E) all of the above
28. Which of the following is true of cellulose?
A) It is a polymer composed of sucrose monomers.
B) It is a storage polysaccharide for energy in plant cells.
C) It is a storage polysaccharide for energy in animal cells.
D) It is a major structural component of plant cell walls.

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E) It is a major structural component of animal cell plasma membranes.
29. Humans can digest starch but not cellulose because
A) the monomer of starch is glucose, while the monomer of cellulose is galactose.
B) humans have enzymes that can hydrolyze the beta (β) glycosidic linkages of starch but not the alpha (α) glycosidic linkages of cellulose.
C) humans have enzymes that can hydrolyze the alpha (α) glycosidic linkages of starch but not the beta (β) glycosidic linkages of cellulose.
D) humans harbor starch-digesting bacteria in the digestive tract.
E) the monomer of starch is glucose, while the monomer of cellulose is maltose.
30. Which of the following is (are) true for the class of large biological molecules known as lipids?
A) They are insoluble in water.
B) They are an important constituent of cell membranes.
C) They contain twice as much energy as an equivalent weight of polysaccharide.
D) Only A and B are correct.
E) A, B, and C are correct.
31. The hydrogenation of vegetable oil would result in which of the following?
A) a decrease in the number of carbon-carbon double bonds in the oil (fat) molecules
B) an increase in the number of hydrogen atoms in the oil (fat) molecule
C) the oil (fat) being a solid at room temperature
D) A and C only
E) A, B, and C
32. Ted argues with Barney that fat (triacylglecerol) molecules have to undergo dehydration reactions; Barney states that because fats are not polymers, they do not require dehydration reactions. Which of the following is true?
A) ester linkages are formed through dehydration
B) no dehydration reactions occur
C) double bonds in fatty acid tails inhibit glycerol’s ability to perform a dehydration reaction
D) B and C
E) all of the above
33. What is NOT a function of proteins?
A) enzymatic
B) defensive
C) storage of heritable information
D) receptors
E) hormones
34. The 20 different amino acids found in polypeptides exhibit different chemical and physical properties because of different
A) carboxyl groups attached to an alpha (α) carbon

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B) amino groups attached to an alpha (α) carbon
C) side chains (R groups).
D) alpha (α) carbons.
E) asymmetric carbons.
35. Which type of interaction stabilizes the alpha (α) helix and the beta (β) pleated sheet structures of proteins?
A) hydrophobic interactions
B) nonpolar covalent bonds
C) ionic bonds
D) hydrogen bonds
E) peptide bonds
36. A strong covalent bond between amino acids that functions in maintaining a polypeptide's specific three-dimensional shape is a (an)
A) ionic bond.
B) hydrophobic interaction.
C) van der Waals interaction.
D) disulfide bond.
E) hydrogen bond.
37. The R group or side chain of the amino acid serine is –CH
2
-OH. The R group or side chain of the amino acid alanine is –CH
3
. Where would you expect to find these amino acids in a globular protein in aqueous solution?
A) Serine would be in the interior, and alanine would be on the exterior of the globular protein.
B) Alanine would be in the interior, and serine would be on the exterior of the globular protein.
C) Both serine and alanine would be in the interior of the globular protein.
D) Both serine and alanine would be on the exterior of the globular protein.
E) Both serine and alanine would be in the interior and on the exterior of the globular protein.
38. What is the term used for a protein molecule that assists in the proper folding of other proteins?
A) tertiary protein
B) chaperonin
C) enzyme protein
D) renaturing protein
E) denaturing protein
39. Altering which of the following levels of structural organization could change the function of a protein?
A) primary
B) secondary
C) tertiary

D) quaternary
E) all of the above
40. Which of the following are nitrogenous bases of the pyrimidine type?
A) guanine and adenine
B) cytosine and uracil
C) thymine and guanine
D) ribose and deoxyribose
E) adenine and thymine
41. If one strand of a DNA molecule has the sequence of bases 5'ATTGCA3', the other complementary strand would have the sequence
A) 5'TAACGT3'.
B) 3'TAACGT5'.
C) 5'UAACGU3'.
D) 3'UAACGU5'.
E) 5'UGCAAU3'.
42. What is true of the 5’ end of DNA?
A) the 5’ carbon of deoxyribose is there
B) a phosphate group is there
C) a nitrogenous base is there
D) A and B
E) all of the above
43. Of the following functions, the major purpose of RNA is to
A) transmit genetic information to offspring.
B) function in the synthesis of protein.
C) make a copy of itself, thus ensuring genetic continuity.
D) act as a pattern or blueprint to form DNA.
E) form the genes of higher organisms.
44. When biologists wish to study the internal ultrastructure of cells, they most likely would use
A) a light microscope.
B) a scanning electron microscope.
C) a transmission electronic microscope.
D) A and C only
E) A, B, and C
45. Which of the following does not contain functional ribosomes?
A) a prokaryotic cell
B) a plant mitochondrion
C) a chloroplast
D) an animal mitochondrion
E) a nucleolus
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46. Which of the following organelles is not a common destination for small vesicles that bud off the Golgi apparatus?
A) plasma membrane
B) lysosomes
C) vacuole
D) endoplasmic reticulum
E) all of the above
47. Which type of organelle is primarily involved in the synthesis of oils, phospholipids, and steroids?
A) ribosome
B) lysosome
C) smooth endoplasmic reticulum
D) mitochondrion
E) contractile vacuole
48. Which of the following structures is most directly associated with the secretion of compounds that will become part of the plant cell wall?
A) smooth ER
B) rough ER
C) plasmodesmata
D) Golgi-derived vesicles
E) Golgi apparatus
49. Of the following, which is probably the most common route for membrane flow in the endomembrane system?
A) Golgi → lysosome → ER → plasma membrane
B) tonoplast → plasma membrane → nuclear envelope → smooth ER
C) nuclear envelope → lysosome → Golgi → plasma membrane
D) rough ER → vesicles → Golgi → plasma membrane
E) ER → chloroplasts → mitochondrion → cell membrane
50. All of the following are correct matches of the location of a protein and the location of its synthesis except
A) plasma membrane protein-rough ER.
B) mitochondrial membrane protein-free cytoplasmic ribosomes.
C) cytoplasmic proteins-free cytoplasmic ribosomes.
D) chloroplast stromal protein-chloroplast ribosomes.
E) mitochondrial matrix protein-rough ER.
51. Motor proteins provide for molecular motion in cells by interacting with what types of cellular structures?
A) sites of energy production in cellular respiration
B) membrane proteins
C) ribosomes

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D) cytoskeletons
E) cellulose fibers in the cell wall
52. Microfilaments are well known for their role in which of the following?
A) ameboid movement
B) formation of cleavage furrows
C) contracting of muscle cells
D) A and B only
E) A, B, and C
53. The cell walls of bacteria, fungi, and plant cells and the extracellular matrix of animal cells are all external to the plasma membrane. Which of the following is not a characteristic of all of these extracellular structures?
A) They must be highly permeable to water and small molecules in order to allow cells to exchange matter and energy with their environment.
B) They must permit information transfer between the cell's external environment and the cytoplasm.
C) They must provide a rigid structure that maintains an appropriate ratio of cell surface area to volume.
D) They are constructed of materials that are largely synthesized in the cytoplasm and then transported out of the cell.
E) They are composed of a mixture of proteins and carbohydrates.
54. The extracellular matrix is thought to participate in the regulation of animal cell behavior by communicating information from the outside to the inside of the cell via
A) gap junctions.
B) the nucleus.
C) DNA and RNA.
D) integrins.
E) plasmodesmata.
55. Ions can travel directly from the cytoplasm of one animal cell to the cytoplasm of an adjacent cell through
A) plasmodesmata.
B) intermediate filaments.
C) tight junctions.
D) desmosomes.
E) gap junctions.