BIOL 212 Section 3
Exam 1
BIOL 212 Exam 1-Section 3
1.1. After observing an abundance of microtubule spindle fibers being associated with the condensed chromosomes during metaphase you state, “Disrupting the assembly of the spindle fiber will disrupt the segregation of the chromosomes during anaphase”. This process can be described as example of …
*A) Hypothesis-Based Science
B) Discovery-Based Science
3.1. Given the data, which of the following conclusions can be drawn?
A) Atoms in gold foil are composed of diffuse, evenly distributed positive charges.
B) Atoms in gold foil are composed of diffuse, evenly distributed negative charges.
*C) Most of the volume of an atom is empty space.
D) Alpa particles do not carry a charge.
4.1 A nitrogen atom contains seven protons and seven neutrons, how many electrons are in the second energy shell?
A) Two
B) Three
C) Four
*D) Five
5.1. Which of the structures shown above is an amino acid?
*1) A
2) B
3) C
4) D
5.2. Which of the structures shown above is a component of a nucleotide?
1) A
2) B
*3) C
4) D
5.3. Which of the structures shown above is part of a lipid?
1) A
2) B
3) C
*4) D
5.4. Which of the structures shown above is a carbohydrate?
1) A
*2) B
3) C
4) D
6.1. Atoms form covalent bonds with each other by:
A) transferring electrons from one atom to the other.
*B) sharing electrons.
C) sharing protons.
D) the attraction of positive and negative charges.
E) sharing neutrons.
6.2. Hydrogen bonds can form
A) between a nitrogen atom and a hydrogen bound to a carbon atom
B) between two hydrogens bound to a carbon atom
*C) between an oxygen atom and a hydrogen bound to an nitrogen atom
D) between an oxygen atom and a nitrogen atom
6.4. The bonding between sodium and chloride in table salt (NaCl) is an example of what type of bonding?
A) Hydrogen bonding
*B) Ionic bonding
C) Covalent bonding
D) Hydrophobic interactions
6.5. What is the difference between covalent bonds and ionic bonds?
A) Covalent bonds involve the sharing of protons between atoms, and ionic bonds involve the sharing of electrons between atoms.
B) Covalent bonds involve the sharing of neutrons between atoms, and ionic bonds involve the sharing of electrons between atoms.
7.1. Cohesion is the tendency for molecules to be attracted to one another. Which of the following properties of water molecules is responsible for the cohesion?
A) hydrophobic interactions
*B) hydrogen bonds
C) ionic bonds
D) nonpolar covalent bonds
E) both A and C
8.3. Which of the following solutions has the greatest concentration of hydrogen ions [H+]?
*A) gastric juice (pH 2)
B) vinegar (pH 3)
C) tomato juice (pH 4)
D) black coffee (pH 5)
E) household bleach (pH 12)
8.4. Pure, freshly-distilled water has a pH of 7. This means that
A) there are no H+ ions in the water.
B) there are no OH- ions in the water.
*C) the concentration of H+ ions in the water equals the concentration of OH- ions in the water.
D) the concentration of H+ ions in the water is 7 times the concentration of OH- ions in the water.
E) The concentration of OH- ions in the water is 7 times the concentration of H+ ions in the water.
9.1. Polysaccharides, nucleic acids, and proteins are similar in that they:
A) are synthesized from monomers by the process of hydrolysis.
*B) are synthesized from monomers by dehydration reactions.
C) are synthesized as a result of peptide bond formation between monomers.
D) are decomposed into their subunits by dehydration reactions.
E) all contain nitrogen in their monomer building blocks.
10.1. If the top image shows glutamine at neutral pH, what would glutamine look like at pH 5?
*1) A
2) B
3) C
12.1. What is the smallest object that can be observed with a typical light microscope? Assuming the object can be appropriately stained for observation.
*A) a mitochondrion
B) a virus particle
C) an animal cell
D) a typical protein molecule
E) a ribosome
F) ATP
13.1. Which of the following would require a transporter or channel in order to cross the membrane?
*A) Na+
B) Ethanol
C) O2
D) H2O
13.2. Which of the following would require a transporter or channel in order to cross the membrane?
A) CO2
B) Ethanol
*C) Lysine (an amino acid)
D) H2O
The above figure shows a solute molecule surrounded by a hydration shell of water.
14.1. Based on your knowledge of the polarity of water molecules, the solute molecule is most likely
*A) positively charged.
B) negatively charged.
C) without charge.
D) hydrophobic.
E) nonpolar.
15.1. If you were to place phospholipids in a beaker of vegetable oil, which picture above best illustrates the way in which the phospholipids might organize? (Note: On each phospholipid molecule, the circle represents the polar head group and the wavy lines represent the acyl fatty acid tails.)
1) A
2) B
*3) C
4) D
16.2. Atlantic Cod, a cold water fish, and Methanopyrus kandleri (M. Kandleri), a bacterium that thrives at temperatures around 100°C, differ in the lipid composition of their cell membranes. What differences would likely be seen based on their habitat temperature?
A) M. kandleri will likely have shorter chain fatty acids in its phospholipids.
B) The Atlantic Cod will have more saturated phospholipids in its cell membranes while M. kandleri will have more unsaturated phospholipids in its cell membrane.
*C) The Atlantic Cod will have more unsaturated phospholipids in its cell membranes while M. kandleri will have more saturated phospholipids in its cell membrane.
D) The Atlantic Cod will have a higher concentration of phospholipids per unit area than M. kandleri.
17.2. Among a cell’s constituents, it has the following: enzymes, DNA, ribosomes, plasma membrane, and mitochondria. It could be:
A) a bacterium, but not a plant cell.
B) an animal cell, but not a plant cell.
C) a plant cell, but not an animal cell.
*D) a plant or an animal cell, but not a bacterium.
18.1. According to the fluid mosaic model of cell membranes, which of the following is a true statement about membrane phospholipids?
*A) Membrane phospholipids can diffuse laterally in the plane of the membrane.
B) They flip-flop from one side of the membrane to the other several times a second.
C) They occur in an uninterrupted bilayer, with membrane proteins restricted to the surface of the membrane.
D) They are free to depart from the membrane and dissolve in the surrounding solution.
19. 3 points
You have attached a fluorescent tag (F) onto a small membrane protein (figure on the left), and you observe in a fluorescence microscope that the membrane containing the protein fluoresces yellow (figure on the right). You shine a laser spot for a moment onto the membrane to irreversibly bleach a small spot containing hundreds of membrane proteins.
19.1. What would you expect to see if the tagged membrane protein was a subunit of a larger membrane protein?
A) The spot would expand slowly.
B) The spot would disappear quickly.
C) The spot would expand quickly.
*D) The spot would disappear slowly.
E) None of the above
19.2. What would you expect to see if the tagged membrane protein was free to diffuse in the plane of the membrane?
A) The spot would expand slowly.
*B) The spot would disappear quickly.
C) The spot would expand quickly.
D) The spot would disappear slowly.
E) None of the above
19.3. What would you expect if the tagged membrane protein was anchored to the cytoskeleton?
A) The spot would expand slowly.
B) The spot would disappear quickly.
C) The spot would expand quickly.
D) The spot would disappear slowly.
*E) None of the above
20.1. In the picture above, of what protein is the fluorescent cytoskeletal composed?
A) keratin
B) carotene
*C) tubulin
D) integrin
E) actin
20.2. In the picture above, of what protein is the fluorescent cytoskeletal composed?
*A) tubulin
B) carotene
C) keratin
D) integrin
E) actin
21.1. If the membrane protein labeled “A” is a Na+/glucose symporter, then what might you expect about the movement of Na+ and/or glucose across the cell membrane?
A) Na+ would likely move from the inside of the cell to the outside.
B) Glucose would likely move from the inside of the cell to the outside.
*C) Glucose would likely move from the outside of the cell to the inside.
D) Glucose would not move because the concentration outside is nearly equal to the concentration inside the cell.
22.1. Which of the following statements is TRUE about facilitated diffusion?
A) It describes the movement of small molecules, like carbon dioxide, across membranes.
B) It requires an expenditure of energy by the cell.
* C) It is a passive process in which molecules move from a region of higher concentration to a region of lower concentration.
D) It is an active process in which molecules move from a region of lower concentration to one of higher concentration.
E) It does not require channel or carrier proteins in the cell membrane.
22.2. Water passes quickly through cell membranes because
A) the bilayer is hydrophilic.
B) it moves through hydrophobic channels.
C) water movement is tied to ATP hydrolysis.
D) it is a small, non polar molecule.
*E) it moves through aquaporins in the membrane.
22.3. When an animal cell is put into a hypotonic solution
*A) Osmosis will cause the cell to swell (and, in some cases, lyse).
B) Osmosis will cause the cell to shrivel and become smaller.
C) There is no net movement of water.
D) Large solutes leave the cell faster than water diffuses into the cell.
24.1. When George Palade conducted his famous pulse-chase experiment to follow the secretion of proteins, he observed the secretion process in pancreas cells of the guinea pig. What might he have seen if he had conducted the same pulse-chase experiment, but had looked at liver cells of baby guinea pigs that are actively making proteins targeted to mitochondria, and not secreted proteins?
A) As before, most of the label immediately following the pulse would have appeared in the ER
B) With a short chase, most of the label would have appeared in the endomembrane system prior to appearing in mitochondria.
*C) Most of the label immediately following the pulse would have appeared in the cytoplasm.
D) After a period of chase, most of the label would have ended in the bloodstream, exported from the mitochondria outside the liver cells.
25.1. The targeting of a protein to lysosomes
A) requires an ER signal sequence on the protein.
B) does not involve post-translational sorting.
C) engages the signal recognition particle at one stage in the sorting process.
*D) all of the above
25.2. The targeting of a protein to the Golgi apparatus
A) does not require an ER signal sequence on the protein.
B) involves post-translational sorting.
*C) engages the signal recognition particle at a stage in the sorting process.
D) all of the above
26.1. The targeting of a protein to the mitochondrial matrix
A) requires an ER signal sequence on the protein.
B) does not involve post-translational sorting.
*C) requires a translocase in the mitochondrial membranes.
D) all of the above
26.2. The targeting of a protein to the mitochondrial matrix
A) does not require an ER signal sequence on the protein.
B) involves post-translational sorting.
C) requires a translocase in the mitochondrial membranes.
*D) all of the above
27.1. If a polypeptide chain emerging from a ribosomeduring translation bears an ER signal sequence, then ……
A) the protein will be sorted to the nucleus, peroxisome or mitochondrion.
*B) the signal recognition particle will bind to the signal sequence and block further translation.
C) the signal recognition particle will bind to the signal sequence and guide the ribosome to the plasma membrane.
D) All of the above.
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