Chapter 5 Test File

22 Questions

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File Management Quizzes & Trivia

This covers chapter 5 test file questions.


Questions and Answers
  • 1. 
    Biological membranes are composed of
    • A. 

      A. nucleotides and nucleosides.

    • B. 

      B. enzymes, electron acceptors, and electron donors.

    • C. 

      C. fatty acids.

    • D. 

      D. monosaccharides.

    • E. 

      E. lipids, proteins, and carbohydrates.

  • 2. 
    7. Peripheral membrane proteins have
    • A. 

      A. hydrophobic regions within the lipid portion of the bilayer.

    • B. 

      B. hydrophilic regions that protrude in aqueous environments on either side of the membrane.

    • C. 

      C. lateral but not vertical movement within the bilayer.

    • D. 

      D. control over the rate of diffusion.

    • E. 

      E. polar regions that interact with similar regions of integral membrane proteins.

  • 3. 
    Which of the following statements about the proteins of the plasma membrane and the proteins of the inner mitochondrial membrane is true?
    • A. 

      A. Both membranes have only peripheral proteins.

    • B. 

      B. Only the mitochondrial membrane has integral proteins.

    • C. 

      C. Only the mitochondrial membrane has peripheral proteins.

    • D. 

      D. All of the proteins from both membranes are hydrophilic.

    • E. 

      E. The two membranes differ in their lipid composition.

  • 4. 
    4. The plasma membrane of animals contains carbohydrates
    • A. 

      A. on the inner side of the membrane, facing the cytosol.

    • B. 

      B. on the outer side of the membrane, protruding into the environment.

    • C. 

      C. on both sides of the membrane.

    • D. 

      D. on neither side of the membrane.

    • E. 

      E. within the membrane.

  • 5. 
    5. In biological membranes, the phospholipids are arranged in a
    • A. 

      A. bilayer, with the fatty acids pointing toward each other.

    • B. 

      B. bilayer, with the fatty acids facing outward.

    • C. 

      C. single layer, with the fatty acids facing the interior of the cell.

    • D. 

      D. single layer, with the phosphorus-containing region facing the interior of the cell.

    • E. 

      E. bilayer, with the phosphorus groups in the interior of the membrane.

  • 6. 
    6. Cholesterol molecules act to
    • A. 

      A. help hold a membrane together.

    • B. 

      B. transport ions across membranes.

    • C. 

      C. attach to carbohydrates.

    • D. 

      D. disrupt membrane function.

    • E. 

      E. alter the fluidity of the membrane.

  • 7. 
    The compounds in biological membranes that form a barrier to the movement of hydrophilic materials across the membrane are
    • A. 

      Integral membrane proteins.

    • B. 

      Carbohydrates.

    • C. 

      Lipids.

    • D. 

      Nucleic acids.

    • E. 

      peripheral membrane proteins.

  • 8. 
    8. The functional roles for different proteins found in membranes include all except
    • A. 

      A. allowing movement of molecules that would otherwise be excluded by the lipid components of the membrane.

    • B. 

      B. transferring signals from outside the cell to inside the cell.

    • C. 

      C. maintaining the shape of the cell.

    • D. 

      D. facilitating the transport of macromolecules across the membrane.

    • E. 

      E. stabilizing the lipid bilayer.

  • 9. 
    9. Houseplants adapted to indoor temperatures may die when accidentally left outdoors in the cold because their
    • A. 

      A. DNA cannot function.

    • B. 

      B. membranes lack adequate fluidity.

    • C. 

      C. photosynthesis is impaired.

    • D. 

      D. chloroplasts malfunction.

    • E. 

      E. membranes need more cholesterol.

  • 10. 
    10. A protein that forms an ion channel through a membrane is most likely to be
    • A. 

      A. a peripheral protein.

    • B. 

      B. a transmembrane protein.

    • C. 

      C. a phospholipid.

    • D. 

      D. an enzyme.

    • E. 

      E. entirely outside the phospholipid bilayer.

  • 11. 
    15. When a mouse cell and a human cell are fused, the membrane proteins of the two cells become uniformly distributed over the surface of the hybrid cell. This occurs because
    • A. 

      A. many proteins can move around within the bilayer.

    • B. 

      B. all proteins are anchored within the membrane.

    • C. 

      C. proteins are asymmetrically distributed within the membrane.

    • D. 

      D. all proteins in the plasma membrane are peripheral.

    • E. 

      E. different membranes contain different proteins.

  • 12. 
    14. Which type of membrane protein would likely be most easily removed in a laboratory experiment?
    • A. 

      A. Integral proteins

    • B. 

      B. Channel proteins

    • C. 

      C. Peripheral proteins

    • D. 

      D. Transmembrane proteins

    • E. 

      E. Gated channels

  • 13. 
    11. The hydrophilic regions of a membrane protein are most likely to be found
    • A. 

      A. only in muscle cell membranes.

    • B. 

      B. associated with the fatty acid region of the lipids.

    • C. 

      C. in the interior of the membrane.

    • D. 

      D. exposed on the surface of the membrane.

    • E. 

      E. either on the surface or inserted into the interior of the membrane.

  • 14. 
    13. The plasma membranes of winter wheat are able to remain fluid when it is extremely cold by
    • A. 

      A. increasing the number of cholesterol molecules present.

    • B. 

      B. closing protein channels.

    • C. 

      C. decreasing the number of hydrophobic proteins present.

    • D. 

      D. replacing saturated fatty acids with unsaturated fatty acids.

    • E. 

      E. using fatty acids with longer tails.

  • 15. 
    17. When a membrane is prepared by freeze-fracture and examined under the electron microscope, the exposed interior of the membrane bilayer appears to be covered with bumps. These bumps are
    • A. 

      A. integral membrane proteins.

    • B. 

      B. ice crystals.

    • C. 

      C. platinum.

    • D. 

      D. organelles.

    • E. 

      E. vesicles.

  • 16. 
    16. The LDL receptor is an integral protein that crosses the plasma membrane, with portions of the protein extending both outside and into the interior of the cell. The amino acid side chains (R groups) in the region of the protein that crosses the membrane are most likely
    • A. 

      A. charged.

    • B. 

      B. hydrophilic.

    • C. 

      C. hydrophobic.

    • D. 

      D. carbohydrates.

    • E. 

      E. lipids.

  • 17. 
    12. A characteristic of plasma membranes that helps them fuse during vesicle formation and phagocytosis is the
    • A. 

      A. ratio of one protein molecule for every 25 phospholipid molecules.

    • B. 

      B. capacity of lipids to associate and maintain a bilayer organization

    • C. 

      C. constant fatty acid chain length and degree of saturation.

    • D. 

      D. ability of phospholipid molecules to flip over and trade places with other phospholipid molecules.

    • E. 

      E. asymmetrical distribution of membrane proteins.

  • 18. 
    18. When vesicles from the Golgi apparatus deliver their contents to the exterior of the cell, they add their membranes to the plasma membrane. The plasma membrane does not increase in size, because
    • A. 

      A. some vesicles from the Golgi apparatus fuse with the lysosomes.

    • B. 

      B. membrane vesicles carry proteins from the endoplasmic reticulum to the Golgi apparatus.

    • C. 

      C. membrane is continually being lost from the plasma membrane by endocytosis.

    • D. 

      D. new phospholipids are synthesized in the endoplasmic reticulum.

    • E. 

      E. the phospholipids become more tightly packed together in the membrane.

  • 19. 
    21. Which of the following represents the correct pathway for the synthesis and secretion of insulin, a protein secreted by the cells of the pancreas?
    • A. 

      A. Rough ER; Golgi apparatus; vesicle; plasma membrane

    • B. 

      B. Golgi apparatus; rough ER; lysosome

    • C. 

      C. Lysosome; vesicle; plasma membrane

    • D. 

      D. Plasma membrane; coated vesicle; lysosome

    • E. 

      E. Rough ER; cytoplasm; plasma membrane

  • 20. 
    19. Protein movement within a membrane may be restricted by
    • A. 

      A. glycolipids and glycoproteins.

    • B. 

      B. closure of gated channels.

    • C. 

      C. the cytoskeleton and lipid rafts.

    • D. 

      D. cell adhesion.

    • E. 

      E. tight junctions and desmosomes.

  • 21. 
    20. Which of the following functions as a recognition signal for interactions between cells?
    • A. 

      A. RNA

    • B. 

      B. Phospholipids

    • C. 

      C. Cholesterol

    • D. 

      D. Fatty acids

    • E. 

      E. Glycolipids

  • 22. 
    22. Which of the following are not specialized cell junctions?
    • A. 

      A. Gap junctions

    • B. 

      B. Tight junctions

    • C. 

      C. Desmosomes

    • D. 

      D. Cytoplasmic plaques

    • E. 

      E. Both a and b