Unformatted text preview: PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK Chapter 1: Cellular Biology
MULTIPLE CHOICE
1. Which statement best describes the cellular function of metabolic absorption?
a. Cells can produce proteins.
c. Cells can take in and use nutrients.
b. Cells can secrete digestive enzymes.
d. Cells can synthesize fats.
ANS: C In metabolic absorption, all cells take in and use nutrients and other substances from their
surroundings. The remaining options are not inclusive in their descriptions of cellular
metabolic absorption.
PTS: 1 REF: Page 2 2. Most of a cell’s genetic information, including RNA and DNA, is contained in the:
a. Mitochondria
c. Nucleolus
b. Ribosome
d. Lysosome
ANS: C The nucleus contains the nucleolus, a small dense structure composed largely of RNA,
most of the cellular DNA, and the DNA-binding proteins, such as the histones, which
regulate its activity. The other options do not contain most of a cell’s genetic information.
PTS: 1 REF: Page 2 3. Which component of the cell produces
hydrogen peroxide (H2O2) by using oxygen to
NURSINGTB.COM remove hydrogen atoms from specific substrates in an oxidative reaction?
a. Lysosomes
c. Ribosomes
b. Peroxisomes
d. Oxyhydrosomes
ANS: B Peroxisomes are so named because they usually contain enzymes that use oxygen to
remove hydrogen atoms from specific substrates in an oxidative reaction that produces
H2O2, which is a powerful oxidant and potentially destructive if it accumulates or escapes
from peroxisomes. Ribosomes are RNA-protein complexes (nucleoproteins) that are
synthesized in the nucleolus and secreted into the cytoplasm through pores in the nuclear
envelope called nuclear pore complexes. Lysosomes are saclike structures that originate
from the Golgi complex and contain more than 40 digestive enzymes called hydrolases,
which catalyze bonds in proteins, lipids, nucleic acids, and carbohydrates. Oxyhydrosomes
are involved in enzyme production.
PTS: 1 REF: Page 8 4. Which cell component is capable of cellular autodigestion when it is released during cell injury?
a. Ribosome
b. Golgi complex c. Smooth endoplasmic reticulum
d. Lysosomes ANS: D NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK The lysosomal membrane acts as a protective shield between the powerful digestive
enzymes within the lysosome and the cytoplasm, preventing their leakage into the
cytoplasmic matrix. Disruption of the membrane by various treatments or cellular injury
leads to a release of the lysosomal enzymes, which can then react with their specific
substrates, causing cellular self-digestion. The other options do not correctly describe this
process.
PTS: 1 REF: Pages 7-8 5. What is the sequence of steps in the development of a digestive enzyme by the pancreas cells from the initial transcription to the release from the cell?
a. The enzyme is transcribed from DNA by RNA in the nucleus, proceeds to the
ribosome for synthesis, and is transported in a secretory vesicle to the cell
membrane.
b. The enzyme is transcribed from RNA by DNA in the nucleus, proceeds to the
lysosome for synthesis, and is transported in an encapsulated membrane to the cell
membrane.
c. The enzyme is transcribed by the mitochondria in the nucleus, proceeds to the
ribosome for synthesis, and is transported in a cytoskeleton to the cell membrane.
d. The enzyme is transcribed from DNA by RNA in the nucleus, proceeds to the
Golgi complex for synthesis, and is transported in a cytosol to the cell membrane.
ANS: A The enzyme is transcribed from DNA by RNA in the nucleus, proceeds to the ribosome
for synthesis, and is transported in a secretory vesicle to the cell membrane. The other
options do not correctly describe this process.
PTS: 1 NURSINGTB.COM REF: Page 7 | Figure 1-5 6. During which phase of the cell cycle is DNA synthesized?
a. G1
c. G2
b. S
d. M
ANS: B The four designated phases of the cell cycle are: (1) the G1 phase (G = gap), which is the
period between the M phase (M = mitosis) and the start of DNA synthesis; (2) the S phase
(S = synthesis), during which DNA is synthesized in the cell nucleus; (3) the G2 phase,
during which RNA and protein synthesis occurs, the period between the completion of
DNA synthesis and the next phase (M); and (4) the M phase, which includes nuclear and
cytoplasmic division.
PTS: 1 REF: Page 37 7. What organic compound facilitates transportation across cell membranes by acting as receptors, transport channels for electrolytes, and enzymes to drive active pumps?
a. Lipids
c. Proteins
b. Proteases
d. Carbohydrates
ANS: C NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK Proteins act as (1) recognition and binding units (receptors) for substances moving in and
out of the cell; (2) pores or transport channels for various electrically charged particles
called ions or electrolytes and specific carriers for amino acids and monosaccharides; and
(3) specific enzymes that drive active pumps that promote the concentration of certain
ions, particularly potassium (K+), within the cell while keeping concentrations of other
ions, for example, sodium (Na+), below the concentrations found in the extracellular
environment. The other options do not correctly describe this process.
PTS: 1 REF: Page 13 | Page 15 8. Understanding the various steps of proteolytic cascades, such as caspase-mediated apoptosis and complement cascades, may be useful in designing drug therapy for which
human diseases?
a. Cardiac and vascular disorders
b. Autoimmune and malignant disorders
c. Gastrointestinal and renal disorders
d. Endocrine and gastrointestinal disorders
ANS: B Understanding the various steps involved in this process is crucial for designing drug
interventions. Dysregulation of proteases features prominently in many human diseases,
including cancer, autoimmunity, and neurodegenerative disorders. The other options do
not correctly describe this process.
PTS: 1 REF: Page 15 9. Which structure prevents water-soluble molecules from entering cells across the plasma membrane?
a. Carbohydrate chains
b. Glycoprotein channels NURSINGTB.COM c. Membrane channel proteins
d. Lipid bilayer ANS: D The bilayer’s structure accounts for one of the essential functions of the plasma
membrane. It is impermeable to most water-soluble molecules (molecules that dissolve in
water) because the water-soluble molecules are insoluble in the oily core region. The
bilayer serves as a barrier to the diffusion of water and hydrophilic substances while
allowing lipid-soluble molecules, such as oxygen (O2) and carbon dioxide (CO2), to
diffuse through it readily. The other options do not correctly describe this process.
PTS: 1 REF: Pages 12-13 10. The fluid mosaic model explains:
a. How a cell membrane functions
b. Why our bodies appear to be solid
c. How tissue is differentiated
d. How fluid moves between the intracellular and extracellular compartments
ANS: A The fluid mosaic model accounts for the flexibility of cellular membranes, their
self-sealing properties, and their impermeability to many substances. The remaining
options do not explain the mosaic model. NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK PTS: 1 REF: Page 12 | What's New box 11. Which form of cell communication is used to communicate within the cell itself and with other cells in direct physical contact?
a. Protein channel (gap junction)
b. Plasma membrane–bound signaling molecules (involving receptors)
c. Hormone secretion such as neurotransmitters
d. Extracellular chemical messengers such as ligands
ANS: A Cells communicate by using hundreds of kinds of signal molecules, for example, insulin.
Cells communicate in three main ways; they display plasma membrane–bound signaling
molecules (receptors) that affect the cell itself and other cells in direct physical contact.
The other options do not correctly describe this process.
PTS: 1 REF: Page 20 12. Which mode of chemical signaling uses blood to transport communication to cells some distance away?
a. Paracrine
b. Autocrine c. Neurotransmitter
d. Hormonal ANS: D Chemical signaling can be classified into three categories: (1) local-chemical mediator, (2)
hormone, and (3) neurotransmitter. In the local-chemical mediator model, the secreted
chemical acts on the cells in the immediate environment. Hormones are used for
communication with distant targetNURSINGTB.COM
cells. For example, cells can secrete a chemical and rely
on the blood system to deliver the signal to a distant cell. Finally, neurotransmitters are
secreted by neurons to stimulate an adjoining cell. For example, a neuron might secrete
acetylcholine to stimulate the movement of a muscle cell.
PTS: 1 REF: Page 20 13. Which mode of chemical signaling uses local chemical mediators that are quickly taken up, destroyed, or immobilized?
a. Paracrine
b. Autocrine c. Neurotransmitter
d. Hormone ANS: A In paracrine signaling, cells secrete local chemical mediators that are quickly taken up,
destroyed, or immobilized. The other options do not correctly describe this process.
PTS: 1 REF: Page 20 14. Neurotransmitters affect the postsynaptic membrane by binding to:
a. Lipids
c. Amphipathic lipids
b. Ribosomes
d. Receptors
ANS: D In each type of chemical signaling, the target cell receives the signal by first attaching to
its receptors. The other options do not correctly describe this process. NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK PTS: 1 REF: Page 17 15. How do cells receive communication from the extracellular fluid surrounding them?
a. Protein channel (gap junction)
b. Plasma membrane–bound signaling molecules (involving receptors)
c. Hormone secretion such as neurotransmitters
d. Chemical messengers such as ligands
ANS: D Cellular communication can occur by the binding of a chemical massager (a ligand) to a
specific membrane receptor that is closely associated with the channel (e.g., G proteins).
The other options do not correctly describe how cells communicate.
PTS: 1 REF: Pages 21-22 16. When a second message is necessary for extracellular communication to be activated, it is provided by which one?
a. Guanosine triphosphate (GTP)
b. Adenosine monophosphate (AMP) c. Adenosine triphosphate (ATP)
d. Guanosine diphosphate (GDP) ANS: B The two major second messenger pathways are cyclic AMP (cAMP) and calcium (Ca++).
PTS: 1 REF: Pages 22-23 17. Under anaerobic conditions, what process provides energy for the cell?
a. Oxidative phosphorylation NURSINGTB.COM
c. Lactolysis
b. Glycolysis
d. Passive transport
ANS: B Glycolysis produces a net of two molecules of ATP per glucose molecule through the
process of oxidation or the removal and transfer of a pair of electrons. The other options
do not correctly identify an anaerobic process that provides energy to the cell.
PTS: 1 REF: Page 28 18. What is the mechanism by which the energy produced from carbohydrates, proteins, and lipids is transferred to adenosine triphosphate (ATP)?
a. Anaerobic glycolysis
c. Oxidative phosphorylation
b. Oxidative cellular metabolism
d. Tricarboxylic acid phosphorylation
ANS: C Oxidative phosphorylation occurs in the mitochondria and is the mechanism by which the
energy produced from carbohydrates, fats, and proteins is transferred to ATP. The other
options do not correctly identify the mechanism described in the question.
PTS: 1 REF: Pages 27-28 19. Passive transport is best described with which statement?
a. Being driven by osmosis, hydrostatic pressure, and diffusion
b. Involving receptors that can bind with substances being transported NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK c. Being capable of transporting macromolecules
d. Requiring energy generated by the cell
ANS: A Water and small electrically uncharged molecules move easily through pores in the plasma
membrane’s lipid bilayer. This process, called passive transport, naturally occurs through
any semipermeable barrier. It is driven by osmosis, hydrostatic pressure, and diffusion, all
of which depend on the laws of physics and do not require life. The other options do not
correctly describe passive transport.
PTS: 1 REF: Page 28 20. Active transport occurs across which type of membranes?
a. Membranes that have a higher concentration of the solute on the outside of the cell
b. Membranes that are semipermeable to water and small electrically uncharged molecules
c. Membranes that have receptors that are capable of binding with the substances to
be transported
d. Membranes that have a cell membrane that is hydrophobic rather than hydrophilic
ANS: C Some molecules are moved into the cell by mechanisms of active transport, which require
receptors that are capable of recognizing and binding with the substance to be transported.
Diffusion is the movement of a solute molecule from an area of greater solute
concentration to an area of lesser solute concentration. Hydrostatic pressure is the
mechanical force of water pushing against cellular membranes. Osmosis is the movement
of water down a concentration gradient; that is, across a semipermeable membrane from a
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region of higher water concentration
to a lower water concentration
PTS: 1 REF: Page 28 21. Which method of transport uses transmembrane proteins with receptors with a high degree of specificity for the substance being transported?
a. Active
c. Transmembranous
b. Mediated
d. Passive
ANS: B Mediated transport (passive and active) involves integral or transmembrane proteins with
receptors having a high degree of specificity for the substance being transported. Inorganic
anions and cations (e.g., Na+, K+, Ca++, chloride [Cl–], bicarbonate [HCO3–]) and charged
and uncharged organic compounds (e.g., amino acids, sugars) require specific transport
systems to facilitate movement through different cellular membranes. The remaining
options do not correctly identify the process described.
PTS: 1 REF: Page 31 22. The movement of fluid across the arterial end of capillary membranes into the interstitial fluid surrounding the capillary is an example of which fluid movement process?
a. Hydrostatic pressure
c. Diffusion
b. Osmosis
d. Active transport
ANS: A NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK Hydrostatic pressure is the mechanical force of water pushing against cellular membranes.
In the vascular system, hydrostatic pressure is the blood pressure generated in vessels by
the contraction of the heart. Blood reaching the capillary bed has a hydrostatic pressure of
25 to 30 mm Hg, which is sufficient force to push water across the thin capillary
membranes into the interstitial space. The remaining options do not correctly identify the
process described.
PTS: 1 REF: Pages 29-30 23. Why is osmolality preferred over osmolarity as the measurement of osmotic activity in the clinical assessment of individuals?
a. Plasma contains sodium and chloride, which influence the volume of solution.
b. Volume affects perfusion more than the weight of solutes.
c. More of the weight of plasma is influenced by solutes, such as protein and glucose,
rather than by water.
d. Osmotic activity depends on the concentration of solutes present in plasma, such as
proteins and glucose.
ANS: C In plasma, less of the plasma weight is water; therefore the overall concentration of
particles is greater. The osmolality will be greater than the osmolarity because of the
smaller proportion of water. Osmolality is thus the preferred measure of osmotic activity
in clinical assessment of individuals.
PTS: 1 REF: Page 30 24. A patient who has diarrhea receives a 3% saline solution intravenously to replace the
NURSINGTB.COM sodium and chloride lost in the stool. What effect will this fluid replacement have on cells?
a. Become hydrated
c. Shrink
b. Swell or burst
d. Divide
ANS: C A hypertonic solution has a concentration of greater than 285 to 294 mOsm/kg. An
example of a hypertonic solution is 3% saline solution. Water can be pulled out of the cells
by a hypertonic solution; therefore the cells shrink. The remaining options do not correctly
describe the effect identified in the stem.
PTS: 1 REF: Page 31 25. The transport of glucose from the blood to the cell is accomplished by which process?
a. Active-mediated transport (active transport)
b. Active diffusion
c. Passive osmosis
d. Passive-mediated transport (facilitated diffusion)
ANS: D Facilitated diffusion is the means by which glucose is transported from the blood to the
cells. The remaining options do not correctly identify this process.
PTS: 1 REF: Pages 31-32 26. Potassium and sodium are transported across plasma membranes by: NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK a.
b.
c.
d. Passive electrolyte channels
Coupled channels
Adenosine triphosphatase (ATPase) enzyme
Diffusion ANS: C The exact mechanism for the transport of Na+ and K+ across the membrane is uncertain.
One proposal is that ATPase enzyme induces the transporter protein to undergo several
conformational changes, causing Na+ and K+ to move short distances (see Figure 1-29).
The remaining options do not correctly describe the means by which K+ and Na+ are
transported.
PTS: 1 REF: Pages 32-33 27. What occurs during exocytosis?
a. Macromolecules can be secreted across eukaryotic cell membranes.
b. All substances are secreted into the cellular matrix.
c. No repairs in the plasma membrane can take place.
d. Solute molecules flow freely into and out of the cell.
ANS: A In eukaryotic cells, secretion of macromolecules almost always occurs by exocytosis. The
remaining options do not correctly describe exocytosis.
PTS: 1 REF: Pages 35-36 28. Why is it possible for potassium to diffuse easily into and out of cells?
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a. Potassium has a greater concentration
in the intracellular fluid (ICF).
b. Sodium has a greater concentration in the extracellular fluid (ECF).
c. The resting plasma membrane is more permeable to potassium.
d. An excess of anions are inside the cell.
ANS: C Because the resting plasma membrane is more permeable to K+ than to Na+, K+ can easily
diffuse from its area of higher concentration in the ICF to its area of lower concentration in
the ECF. Because Na+ and K+ are both cations, the net result is an excess of anions inside
the cell, resulting in the resting membrane potential. The remaining options do not
correctly identify the process that most easily diffuses K+.
PTS: 1 REF: Page 36 29. The cellular uptake of the nutrient cholesterol depends on which process?
a. Receptor-mediated exocytosis
c. Receptor-mediated endocytosis
b. Antiport system
d. Passive transport
ANS: C The cellular uptake of nutrients, such as cholesterol, for example, depends on
receptor-mediated endocytosis. Nutrients are not transported via the other options.
PTS: 1 REF: Page 33 NURSINGTB.COM PATHOPHYSIOLOGY 8TH EDITION MCCANCE TEST BANK 30. What causes the rapid change in the resting membrane potential to initiate an action potential?
a. Potassium gates open, and potassium rushes into the cell, changing the membrane
potential from negative to positive.
b. Sodium gates open, and sodium rushes into the cell, changing the membrane
potential from negative to positive.
c. Sodium gates close, allowing potassium into the cell to change the membrane
potential from positive to negative.
d. Potassium gates close, allowing sodium into the cell to change the membrane
potential from positive to negative.
ANS: B When a resting cell is stimulated through voltage-regulated channels, the cell membranes
become more permeable to Na+. A net Na+ moves into the cell, and the membrane
potential decreases, or moves forward, from a negative value (in millivolts) to zero. The
Na+ gates open, and Na+ rushes into the cell, causing the membrane potential to reduce to
zero and then become positive (depolarization). The remaining options do not correctly
describe the change that initiates an action potential.
PTS: 1 REF: Page 36 31. The action of platelet-derived growth factor is to stimulate the production of which cells?
a. Platelets
c. Connective tissue cells
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