BSCI105 Exam 2 Sample Questions (Multiple Choice) with Answers
BSCI105 Exam 2 Sample Questions (Multiple Choice) with Answers Bsci105
Popular in Intro to biological sciences
Popular in Biological Sciences
This 9 page Class Notes was uploaded by clcindy.lin on Thursday March 10, 2016. The Class Notes belongs to Bsci105 at University of Maryland taught by Dr. Alewall in Summer 2015. Since its upload, it has received 24 views. For similar materials see Intro to biological sciences in Biological Sciences at University of Maryland.
Reviews for BSCI105 Exam 2 Sample Questions (Multiple Choice) with Answers
Report this Material
What is Karma?
Karma is the currency of StudySoup.
You can buy or earn more Karma at anytime and redeem it for class notes, study guides, flashcards, and more!
Date Created: 03/10/16
Student Name_________________________________ TeachingAsst_________________________________ Second Exam BSCI 105 NAllewell October 19, 2015 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which structure is the site of the synthesis of proteins that may be exported from the cell? 1) A) rough ER B) Golgi vesicles C) free cytoplasmic ribosomes D) plasmodesmata 2) Which of the following produces and modiﬁes polysaccharides that will be secreted? 2) A) mitochondrion B) lysosome C) Golgi apparatus D) peroxisome 3) Which organelle is the primary site of ATPsynthesis in eukaryotic cells? 3) A) mitochondrion B) lysosome C) peroxisome D) Golgi apparatus 4) Thylakoids, DNA, and ribosomes are all components found in _____. 4) A) nuclei B) chloroplasts C) lysosomes D) mitochondria 5) The evolution of eukaryotic cells most likely involved _____. 5) A) endosymbiosis of an aerobic bacterium in a larger host cell—the endosymbiont evolved into mitochondria B) an endosymbiotic fungal cell evolving into the nucleus C) anaerobic archaea taking up residence inside a larger bacterial host cell to escape toxic oxygen—the anaerobic bacterium evolved into chloroplasts D) acquisition of an endomembrane system and subsequent evolution of mitochondria from a portion of the Golgi 6) The extracellular matrix is thought to participate in the regulation of animal cell behavior by 6) communicating information from the outside to the inside of the cell via which of the following? A) the nucleus B) integrins C) gap junctions D) DNA and RNA 7) Plasmodesmata in plant cells are most similar in function to which of the following structures in 7) animal cells? A) extracellular matrix B) tight junctions C) gap junctions D) desmosomes 1 8) Which of the following statements about the cytoskeleton is true? 8) A) Microtubules are a major component of rhe spindle that forms during mitosis in eukaryotic cells B) Chemicals that block the assembly of the cytoskeleton would have little effect on a cell's response to external stimuli. C) Although microtubules are common within a cell, actin ﬁlaments are rarely found outside of the nucleus. D) The cytoskeleton of eukaryotes is a static structure most resembling scaffolding used at construction sites. 9) Youhave a planar bilayer with equal amounts of saturated and unsaturated phospholipids. 9) After testing the permeability of this membrane to glucose, you increase the proportion of unsaturated phospholipids in the bilayer. What will happen to the membrane's permeability to glucose? A) Permeability to glucose will decrease. B) Permeability to glucose will stay the same. C) Permeability to glucose will increase. D) Youcannot predict the outcome. Yousimply have to make the measurement. 10) Why are lipids and proteins free to move laterally in membranes? 10) A) Lipids and proteins repulse each other in the membrane. B) There are only weak hydrophobic interactions in the interior of the membrane. C) The interior of the membrane is ﬁlled with liquid water. D) Hydrophilic portions of the lipids are in the interior of the membrane. For the following questions, match the labeled component of the cell membrane in the ﬁgure with its description. 11) Which component is a peripheral protein? 11) A) A B) B C) C D) D 12) Which component is a protein ﬁber of the extracellular matrix? 12) A) A B) B C) C D) E 13) Which component is a glycolipid? 13) A) A B) B C) C D) E 2 14) Youare working on a team that is designing a new drug. For this drug to work, it must enter the 14) cytoplasm of speciﬁc target cells. Which of the following would be a factor that determines whether the molecule selectively enters the target cells? A) lack of charge on the drug molecule B) hydrophobicity of the drug molecule C) lipid composition of the target cells' plasma membrane D) similarity of the drug molecule to other molecules transported by the target cells 15) Which of the following is true of osmosis? 15) A) Osmosis only takes place in red blood cells. B) In osmosis, water moves across a membrane from areas of lower solute concentration to areas of higher solute concentration. C) In osmosis, solutes move across a membrane from areas of lower water concentration to areas of higher water concentration. D) Osmosis is an energy-demanding or "active" process. 16) A patient was involved a serious accident and lost a large quantity of blood. In an attempt to 16) replenish body ﬂuids, distilled water—equal to the volume of blood lost—is added to the blood directly via one of his veins. What will be the most probable result of this transfusion? A) The patient's red blood cells will shrivel up because the blood has become hypertonic compared to the cells. B) The patient's red blood cells will shrivel up because the blood has become hypotonic compared to the cells. C) The patient's red blood cells will burst because the blood has become hypertonic compared to the cells. D) The patient's red blood cells will swell and possibly burst because the blood has become hypotonic compared to the cells. 17) When a plant cell, such as one from a rose stem, is submerged in a very hypotonic solution, what 17) is likely to occur? A) The cell will burst. B) The cell will become turgid. C) Plasmolysis will shrink the interior. D) The cell will become ﬂaccid. 18) The phosphate transport system in bacteria imports phosphate into the cell even when the 18) concentration of phosphate outside the cell is much lower than the cytoplasmic phosphate concentration. Phosphate import depends on a pH gradient across the membrane—more acidic outside the cell than inside the cell. Phosphate transport is an example of _____. A) cotransport B) active transport C) facilitated diffusion D) passive diffusion 19) Proton pumps are used in various ways by members of every domain of organisms: Bacteria, 19) Archaea, and Eukarya. What does this most probably mean? A) Cells of each domain evolved proton pumps independently when oceans became more acidic. B) Proton pumps are necessary to all cell membranes. C) Proton gradients across a membrane were used by cells that were the common ancestor of all three domains of life. D) The high concentration of protons in the ancient atmosphere must have necessitated a pump mechanism. 3 20) An organism with a cell wall would most likely be unable to take in materials through _____. 20) A) active transport B) facilitated diffusion C) osmosis D) phagocytosis 21) The difference between pinocytosis and receptor-mediated endocytosis is that _____. 21) A) pinocytosis is nonselective in the molecules it brings into the cell, whereas receptor-mediated endocytosis offers more selectivity. B) pinocytosis can concentrate substances from the extracellular ﬂuid, but receptor-mediated endocytosis cannot. C) pinocytosis increases the surface area of the plasma membrane, whereas receptor-mediated endocytosis decreases the plasma membrane surface area. D) pinocytosis brings only water molecules into the cell, but receptor-mediated endocytosis brings in other molecules as well. 22) White blood cells engulf bacteria using _____. 22) A) pinocytosis B) osmosis C) receptor-mediated exocytosis D) phagocytosis 23) In an HIV-infected cell producing HIV virus particles, the viral glycoprotein is expressed on the 23) plasma membrane. How do the viral glycoproteins get to the plasma membrane? They are synthesized _____. A) by ribosomes in the rough ER and arrive at the plasma membrane in the membrane of secretory vesicles B) by ribosomes in the rough ER, secreted from the cell, and inserted into the plasma membrane from the outside C) on free cytoplasmic ribosomes and then inserted into the plasma membrane D) on ribosomes on the plasma membrane 24) Which of the following statements is representative of the second law of thermodynamics? 24) A) Every energy transformation by a cell decreases the entropy of the universe. B) Without an input of energy, organisms would tend toward decreasing entropy. C) Cells require a constant input of energy to maintain their high level of organization. D) Conversion of energy from one form to another is always accompanied by some gain of free energy. 4 25) Which term most precisely describes the cellular process of breaking down large molecules into 25) smaller ones? A) metabolism B) dehydration C) catabolism (catabolic pathways) D) anabolism (anabolic pathways) 26) Choose the pair of terms that correctly completes this sentence: Catabolism is to anabolism as 26) _____ is to _____. A) free energy; entropy B) exergonic; spontaneous C) work; energy D) exergonic; endergonic 27) The force driving simple diffusion is _____, while the energy source for active transport is _____. 27) A) the concentration gradient; ADP B) transmembrane pumps; electron transport C) the concentration gradient; ATP D) phosphorylated protein carriers; ATP 28) Which of the following is the most correct interpretation of the ﬁgure? 28) A) ATPis a molecule that acts as an intermediary to store energy for cellular work. B) iacts as a shuttle molecule to move energy from ATPto ADP. C) Energy from catabolism can be used directly for performing cellular work. D) ADP + iare a set of molecules that store energy for catabolism. 5 Activity of various enzymes at various temperatures (a) and at various pH (b). 29) Which temperature and pH proﬁle curves on the graphs shown above were most likely 29) generated from analysis of an enzyme from a human stomach where conditions are strongly acid? A) curves 3 and 4 B) curves 1 and 4 C) curves 2 and 4 D) curves 1 and 5 The following questions are based on the reactionA+B ↔C +D shown in the accompanying ﬁgure. 30) Which of the following in the ﬁgure would be the same in either an enzyme-catalyzed or a 30) noncatalyzed reaction? A) a B) b C) c D) d 6 31) Which of the following represents the activation energy required for the enzyme-catalyzed 31) reaction in the ﬁgure? A) a B) b C) c D) d Use the following information to answer the question below. Succinate dehydrogenase catalyzes the conversion of succinate to fumarate. The reaction is inhibited by malonic acid, which resembles succinate but cannot be acted upon by succinate dehydrogenase. Increasing the ratio of succinate to malonic acid reduces the inhibitory effect of malonic acid. 32) Based on this information, which of the following is correct? 32) A) Succinate dehydrogenase is the enzyme, and malonic acid is the substrate. B) Succinate is the substrate, and fumarate is the product. C) Fumarate is the product, and malonic acid is a noncompetitive inhibitor. D) Succinate dehydrogenase is the enzyme, and fumarate is the substrate. 33) A popular strategy for developing new antibiotics (drugs that kill infectious bacteria) is to 33) identify enzymes that are required for the bacteria to reproduce, determine their three-dimensional structures, and look for chemical compounds that would ﬁt into their active sites and block them. If this strategy were successful, it would be an example of what phenomenon? A) allosteric regulation B) competitive inhibition C) vaccination D) denaturation Use the following information to answer the next two questions. A series of enzymes catalyze the reaction X→ Y→ Z→ A. Product A binds to the enzyme that converts X to Y at a position remote from its active site. This binding decreases the activity of the enzyme. 34) With respect to the enzyme that converts X to Y,substance A functions as _____. 34) A) an allosteric inhibitor B) an intermediate C) a competitive inhibitor D) the substrate 35) What is substance X? 35) A) the product B) an intermediate C) an allosteric inhibitor D) a substrate 36) Youhave isolated a previously unstudied protein, identiﬁed its complete structure in detail, and 36) determined that it catalyzes the breakdown of a large substrate. Younotice it has two binding sites. One of these is large, apparently the bonding site for the large substrate; the other is small, possibly a binding site for a regulatory molecule. What do these ﬁndings tell you about the mechanism of this protein? A) It is probably an enzyme that works through competitive inhibition. B) It is probably a cell membrane transport protein–like an ion channel. C) It is probably a structural protein that is involved in cell-to-cell adhesion. D) It is probably an enzyme that works through allosteric regulation. 7 37) The molecule that functions as the reducing agent (electron donor) in a redox or 37) oxidation-reduction reaction _____. A) loses electrons and gains potential energy B) gains electrons and loses potential energy C) loses electrons and loses potential energy D) gains electrons and gains potential energy 38) Which of the listed statements describes the results of the following reaction? 38) C H O +6 O →6 CO +6 H O +Energy 6 12 6 2 2 2 A) O 2s reduced and CO is2oxidized. B) O is oxidized and H O is reduced. 2 2 C) C6 12 6s oxidized and O is 2educed. D) CO is reduced and O is oxidized. 2 2 39) When a molecule of NAD (nicotinamide adenine dinucleotide) gains a hydrogen atom (not a 39) proton), the molecule becomes _____. A) reduced B) oxidized C) redoxed D) dehydrogenated 40) Which one of the following is formed by the removal of a carbon (as CO2) from a molecule of 40) pyruvate? A) glyceraldehyde 3-phosphate B) oxaloacetate C) citrate D) acetyl CoA 41) Which of the following events takes place in the electron transport chain? 41) A) the breakdown of an acetyl group to carbon dioxide B) the breakdown of glucose into two pyruvate molecules C) the extraction of energy from high-energy electrons remaining from glycolysis and the citric acid cycle D) substrate-level phosphorylation 42) Where are the proteins of the electron transport chain located? 42) A) mitochondrial outer membrane B) mitochondrial intermembrane space C) mitochondrial matrix D) mitochondrial inner membrane 43) The primary role of oxygen in cellular respiration is to _____. 43) A) act as an acceptor for electrons and hydrogen, forming water B) combine with lactate, forming pyruvate C) combine with carbon, forming CO 2 D) yield energy in the form of ATPas it is passed down the respiratory chain 44) Why is glycolysis considered to be one of the ﬁrst metabolic pathways to have evolved? 44) A) It produces much less ATPthan does oxidative phosphorylation. B) It requires the presence of membrane-enclosed cell organelles found only in eukaryotic cells. C) It is found in prokaryotic cells but not in eukaryotic cells. D) It does not involve organelles or specialized structures, does not require oxygen, and is present in most organisms. 8 Answer Key Testname: EXAM_2_FALL_2015_FIN 1) A 2) C 3) A 4) B 5) A 6) B 7) C 8) A 9) C 10) B 11) D 12) A 13) B 14) D 15) B 16) D 17) B 18) A 19) C 20) D 21) A 22) D 23) A 24) C 25) C 26) D 27) C 28) A 29) B 30) D 31) B 32) B 33) B 34) A 35) D 36) D 37) C 38) C 39) A 40) D 41) C 42) D 43) A 44) D 9
Are you sure you want to buy this material for
You're already Subscribed!
Looks like you've already subscribed to StudySoup, you won't need to purchase another subscription to get this material. To access this material simply click 'View Full Document'