A 19-Year-Old Man Comes to the Physician Due to Diarrhea

question 237

Multiple Choice

A 19-year-old man comes to the physician due to diarrhea for the last 4 months.  He visited a student health clinic at his university a month ago and was prescribed a course of antibiotics, but his diarrhea failed to improve.  He also has persistent nausea, a bloating sensation, and a 6.8-kg (15-lb) weight loss.  Microscopic examination of his stool for ova and parasites following trichrome staining is shown in the exhibit. 
Impairment of which of the following immune functions would most likely predispose to this patient's infection?

• A)Bacterial killing by neutrophils
• B)CD8+ T lymphocyte-mediated cytotoxicity
• C)Eosinophil-mediated cytotoxicity
• D)Membrane attack complex formation
• E)Secretory IgA production

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Definitions:

Nucleotide Sequences

The precise order of nucleotides (adenine, thymine, cytosine, and guanine) within a DNA or RNA molecule, which encodes genetic information.

Evolutionary Relationships

Connections among species or groups based on common ancestry and genetic heritage, often illustrated by evolutionary trees.

Historical Record

Documented evidence of past events, including written records, artifacts, and oral histories, which serve as sources for historical research.

Diversity

The range of different species, genetic variations, and ecosystems found within and across environments.