Test Bank For McCance & Huether’s Pathophysiology The Biologic Basis for Disease in Adults and Children 9th Edition

Chapter 2: Altered Cellular and Tissue Biology MULTIPLE CHOICE

1. Which type of cell adaptation occurs when normal columnar ciliated epithelial cells of the bronchial lining have been replaced by stratified squamous epithelial cells?
a. Hyperplasia c. Dysplasia
b. Metaplasia d. Anaplasia

ANS: B
Metaplasia is the reversible replacement of one mature cell by another, sometimes a less differentiated cell type. The best example of metaplasia is the replacement of normal columnar ciliated epithelial cells of the bronchial (airway) lining by stratified squamous epithelial cells. The other options do not accurately describe the event in the question.

PTS: 1 REF: Page 54

2. The loss of the adenosine triphosphate (ATP) during ischemia causes cells to:

1. Shrink because of the influx of calcium (Ca).
2. Shrink because of the influx of potassium chloride (KCl).
3. Swell because of the influx of sodium chloride (NaCl).
4. Swell because of the influx of nitric oxide (NO).

ANS: C
A reduction in ATP levels causes the plasma membrane’s sodium-potassium (Na+–K+) pump and sodium-calcium exchange to fail, which leads to an intracellular accumulation of sodium and calcium and diffusiNoUnRoSfINpoGtTaBss.CiuOmMout of the cell. (The Na+–K+ pump is discussed in Chapter 1.) Sodium and water can then freely enter the cell, and cellular swelling results. The other options do not accurately describe the result of ATP at the cellular level.

PTS: 1 REF: Page 57

3. The mammary glands enlarge during pregnancy primarily as a consequence of hormonal: a. Atrophy c. Anaplasia
b. Hyperplasia d. Dysplasia

ANS: B
Hormonal hyperplasia occurs chiefly in estrogen-dependent organs, such as the uterus and breast. The remaining options do not adequately describe the consequence of hormones on breast tissue during pregnancy.

PTS: 1 REF: Page 53

4. Free radicals play a major role in the initiation and progression of which diseases?

1. Cardiovascular diseases such as hypertension and ischemic heart disease
2. Renal diseases such as acute tubular necrosis and glomerulonephritis
3. Gastrointestinal diseases such as peptic ulcer disease and Crohn disease
4. Muscular disease such as muscular dystrophy and fibromyalgia

ANS: A

Emerging data indicate that reactive oxygen species play major roles in the initiation and progression of cardiovascular alterations associated with hyperlipidemia, diabetes mellitus, hypertension, ischemic heart disease, and chronic heart failure. No current research connects the disorders mentioned in the other options to the effects of free radicals.

PTS: 1 REF: Pages 59-60

5. Free radicals cause cell damage by:

1. Stealing the cell’s oxygen to stabilize the electron, thus causing hypoxia
2. Stimulating the release of lysosomal enzymes that digest the cell membranes
3. Transferring one of its charged, stabilized atoms to the cell membrane, which

   causes lysis

4. Giving up an electron, which causes injury to the chemical bonds of the cell

   membrane

ANS: D
A free radical is an electrically uncharged atom or group of atoms having an unpaired electron. Having one unpaired electron makes the molecule unstable; thus to stabilize, the molecule gives up an electron to another molecule or steals one. Therefore it is capable of forming injurious chemical bonds with proteins, lipids, or carbohydrates—key molecules in membranes and nucleic acids. The remaining options do not accurately describe the role played by free radicals in cell damage.

PTS: 1 REF: Page 60

6. What is a consequence of plasma membrane damage to the mitochondria?

1. Enzymatic digestion halts DNA synthesis.
2. Influx of calcium ions halts ATP production.
3. Edema from an influx in sodium causes a reduction in ATP production.
4. Potassium shifts out of the mitochondria, which destroys the infrastructure.

ANS: B
The most serious consequence of plasma membrane damage is, as in hypoxic injury, to the mitochondria. An influx of calcium ions from the extracellular compartment activates multiple enzyme systems, resulting in cytoskeleton disruption, membrane damage, activation of inflammation, and eventually DNA degradation. Calcium ion accumulation in the mitochondria causes the mitochondria to swell, which is an occurrence that is associated with irreversible cellular injury. The injured mitochondria can no longer generate ATP, but they do continue to accumulate calcium ions. The remaining options do not accurately describe the consequence of plasma membrane damage to the mitochondria.

PTS: 1 REF: Page 63

7. What is a consequence of leakage of lysosomal enzymes during chemical injury?

1. Enzymatic digestion of the nucleus and nucleolus occurs, halting DNA synthesis.
2. Influx of potassium ions into the mitochondria occurs, halting the ATP production.
3. Edema of the Golgi body occurs, preventing the transport of proteins out of the

   cell.

4. Shift of calcium out of the plasma membrane occurs, destroying the cytoskeleton.

ANS: A

Enzymatic digestion of cellular organelles, including the nucleus and nucleolus, ensues, halting the synthesis of DNA and ribonucleic acid (RNA). The remaining options do not accurately describe the consequence of lysosomal enzyme leakage during chemical injury.

PTS: 1 REF: Page 63

8. Lead causes damage within the cell by interfering with the action of:

1. Sodium and chloride c. Calcium
2. Potassium d. ATP

ANS: C
Lead affects many different biological activities at the cellular and molecular levels, many of which may be related to its ability to interfere with the functions of calcium. Lead does not appear to cause damage by interfering with the action of the other options.