Cell injury mcqs — Past Paper Questions & Answers MCQs

Question 1

A 19-year-old woman gives birth to her first child. She begins breast feeding the infant. She continues breast feeding for almost a year with no difficulties and no complications. Which of the following cellular processes that began in the breast during pregnancy allowed her to nurse the infant for this period of time?

Accepted Answer

Lobular hyperplasia — There is an increase in the breast lobules under hormonal influence, primarily progesterone with pregnancy, to provide for lactation. ---

Question 2

In an experiment, a series of immunohistochemical stains are employed to identify different cellular components. One particular stain identifies the presence of intermediate filaments within cells. This cytokeratin stain is most likely to be useful for which of the following diagnostic purposes?

Accepted Answer

A neoplasm is determined to be a carcinoma — Carcinomas are derived from epithelium and contain cytokeratins, while sarcomas derived from mesenchymal cells contain vimentin. ---

Question 3

A study is performed to identify predisposing risks for tissue cellular changes. In some persons epithelial metaplasia occurs. In which of the following situations is the process of epithelial metaplasia most likely to take place?

Accepted Answer

Vitamin A deficiency — Vitamin A is necessary to maintain epithelia, and squamous metaplasia of the respiratory tract may occur if there is vitamin A deficiency. The stratified squamous epithelium does not function as well as the normal pseudostratified columnar respiratory epithelium, and there is an increased risk for respiratory infections. ---

Question 4

An 18-year-old primigravida measures 18 weeks' gestation on examination. Ultrasound examination shows a uniformly enlarged uterus. Which of the following cellular changes leads to this increase in uterine size?

Accepted Answer

Myometrial hypertrophy — This cellular hypertrophy of the myometrium of the uterus with increase in cell size (not hyperplasia with increase in cell number) accounts for most of the marked increase in size of the uterus during pregnancy. Following pregnancy and reduction in hormonal stimulation, the uterus returns back to its normal size. ---

Question 5

A 17-year-old adolescent receives whole body radiation as part of a preparatory regimen for bone marrow transplantation to treat acute lymphocytic leukemia. Which of the following cells and tissues in the body is most likely to remain unaltered by the effects of this therapeutic radiation?

Accepted Answer

Neurons of cerebral cortex — Neurons are terminally differentiated cells that do not actively divide or proliferate, so at therapeutic doses of radiation, they are relatively radioresistant. However, at higher radiation doses, cerebral injury does occur from damage mainly to white matter and to the vasculature. ---

Question 6

A 22-year-old woman has a congenital anemia. She has required multiple transfusions of red blood cells for many years. She now has a darker bronze colour to her skin on physical examination. Which of the following microscopic findings would most likely present in her liver?

Accepted Answer

Hemosiderin in hepatocytes — There is 250 mg of iron in each unit of blood. The body has no mechanism for getting rid of excess iron. A small amount of iron is lost with normal desquamation of epithelia, and menstruating women will lose a bit more. The excess iron becomes storage iron, or hemosiderin. Over time, hemosiderosis involves more and more tissues of the body, particularly the liver, but also skin (bronze colour), heart (with heart failure), and pancreas (with diabetes mellitus). ---

Question 7

A 71-year-old man has difficulty with urination. His urinary retention leads to numerous trips to the restroom per day. On digital rectal examination is prostate is diffusely enlarged. Which of the following represents a pathologic change leading to this man's problem?

Accepted Answer

Hyperplasia — Prostatic hyperplasia is an example of pathologic hyperplasia in which prostatic cells become more sensitive to hormonal stimuli for growth. Both glands and stroma can increase in amount. Hyperplasia is an increase in the number of cells. ---

Question 8

A 30-year-old ingests a large amount of acetaminophen and 12 hours later develops malaise and abdominal pain. Laboratory studies show an elevated ALT. N-acetylcysteine is administered to aid in generation of which of the following enzymes within cells as a protective mechanism to reduce the number of free radicals?

Accepted Answer

Glutathione peroxidase — The glutathione peroxidase system is designed to help break down free radicals generated from various forms of cell injury. This system works constantly in the background with small numbers of free radicals. Disease processes generating greater amounts of free radicals and cell injury can overwhelm this system, as with acetaminophen toxicity to hepatocytes in this case. ---

Question 9

A 45-year-old man has a traumatic injury to his forearm and incurs extensive blood loss. On physical examination in the emergency department his blood pressure is 70/30 mm Hg. Which of the following cellular changes is most likely to represent irreversible cellular injury as a result of this injury?

Accepted Answer

Nuclear pyknosis — The hypotension leads to diminished tissue perfusion with ischemic injury. Nuclear chromatin clumping is reversible, but nuclear pyknosis is not. ---

Cell injury mcqs — Past Paper Questions & Answers MCQs

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