Campbell's Biology, 9e (Reece et al.)Chapter 6 A Tour of the CellThis chapter introduces the topics of microscopy and cell fractionation, followed by a review of the cell and the major organelles and structures of eukaryotic cells. A challenge with this chapter is to keep this data from simply being a list of parts. In addition to the structure and function of individual organelles, questions probe student understanding of the cell as a dynamic, interconnected system: the flow of membrane and proteins in the endomembrane system to the plasma membrane; the flow of information from the nucleus to the cytoplasm; and the connection between the cytoskeleton, the plasma membrane, and the extracellular matrix. An evolutionary perspective goes beyond structural distinctions between prokaryotes and eukaryotes to examine theories concerning the evolutionary origins of eukaryotes and key eukaryotic cell structures. Multiple-Choice Questions1) When biologists wish to study the internal ultrastructure of cells, they can achieve the finest resolution by usingA) a phase-contrast light microscope.B) a scanning electron microscope.C) a transmission electronic microscope.D) a confocal fluorescence microscope.E) a super-resolution fluorescence microscope.Answer: CTopic: Concept 6.1Skill: Knowledge/Comprehension2) The advantage of light microscopy over electron microscopy is thatA) light microscopy provides for higher magnification than electron microscopy.B) light microscopy provides for higher resolving power than electron microscopy.C) light microscopy allows one to view dynamic processes in living cells.D) light microscopy provides higher contrast than electron microscopy.E) specimen preparation for light microcopy does not produce artifacts.Answer: CTopic: Concept 6.1Skill: Knowledge/Comprehension3) A primary objective of cell fractionation is toA) view the structure of cell membranes.B) sort cells based on their size and weight.C) determine the size of various organelles.D) separate the major organelles so that their particular functions can be determined.E) separate lipid-soluble from water-soluble molecules.Answer: DTopic: Concept 6.1Skill: Knowledge/Comprehension1Copyright © 2011 Pearson Education, Inc.4) In the fractionation of homogenized cells using centrifugation, the primary factor that determines whether a specific cellular component ends up in the supernatant or the pellet isA) the relative solubility of the component.B) the size and weight of the component.C) the percentage of carbohydrates in the component.D) the presence or absence of nucleic acids in the component.E) the presence or absence of lipids in the component.Answer: BTopic: Concept 6.1Skill: Knowledge/Comprehension5) Which of the following correctly lists the order in which cellular components will be found in the pellet when homogenized cells are treated with increasingly rapid spins in a centrifuge?A) ribosomes, nucleus, mitochondriaB) chloroplasts, ribosomes, vacuolesC) nucleus, ribosomes, chloroplastsD) vacuoles, ribosomes, nucleusE) nucleus, mitochondria, ribosomesAnswer: ETopic: Concept 6.1Skill: Application/Analysis6) Green fluorescent protein (GFP) can be used to fluorescently label a specific protein in cells by genetically engineering cells to synthesize the target protein fused to GFP. What is the advantage of using GFP fusions to visualize specific proteins, instead of staining cells with fluorescently labeled probes that bind to the target protein?A) GFP fusions enable one to track changes in the location of the protein in living cells; staining usually requires preserved cells.B) GFP fusions enable higher resolution than staining with fluorescent probes.C) GFP permits the position of the protein in the cell more precisely than fluorescent probes.D) GFP permits visualization of protein-protein interactions; fluorescent probes do not.E) GFP fusions are not subject to artifacts; fluorescent probes may introduce background artifacts.Answer: ATopic: Concept 6.1Skill: Application/Analysis7) What is the reason that a modern electron microscope (TEM) can resolve biological images to the subnanometer level, as opposed to tens of nanometers achievable for the best super-resolution light microscope?A) The focal length of the electron microscope is significantly longer.B) Contrast is enhanced by staining with atoms of heavy metal.C) Electron beams have much shorter wavelengths than visible light.D) The electron microscope has a much greater ratio of image size to real size.E) The electron microscope cannot image whole cells at one time.Answer: CTopic: Concept 6.1Skill: Application/Analysis2Copyright © 2011 Pearson Education, Inc.8) What technique would be most appropriate to use to observe the movements of condensed chromosomes during cell division?A) light microscopyB) scanning electron microscopyC) transmission electron microscopyD) confocal fluorescence microscopyE) super-resolution fluorescence microscopyAnswer: ATopic: Concept 6.1Skill: Synthesis/Evaluation9) All of the following are part of a prokaryotic cell exceptA) DNA.B) a cell wall.C) a plasma membrane.D) ribosomes.E) an endoplasmic reticulum.Answer: ETopic: Concept 6.2Skill: Knowledge/Comprehension10) The volume enclosed by the plasma membrane of plant cells is often much larger than the corresponding volume in animal cells. The most reasonable explanation for this observation is thatA) plant cells are capable of having a much higher surface-to-volume ratio than animal cells.B) plant cells have a much more highly convoluted (folded) plasma membrane than animal cells.C) plant cells contain a large vacuole that reduces the volume of the cytoplasm.D) animal cells are more spherical, whereas plant cells are elongated.E) plant cells can have lower surface-to-volume ratios than animal cells because plant cells synthesize their own nutrients.Answer: CTopic: Concept 6.2Skill: Synthesis/Evaluation11) A mycoplasma is an organism with a diameter between 0.1 and 1.0 µm. What does the organism's size tell you about how it might be classified?A) It must be a single-celled protist.B) It must be a single-celled fungus.C) It could be almost any typical bacterium.D) It could be a typical virus.E) It could be a very small bacterium.Answer: ETopic: Concept 6.2Skill: Application/Analysis3Copyright © 2011 Pearson Education, Inc.12) Which of the following is a major cause of the size limits for certain types of cells?A) limitation on the