A 5-Year-Old Boy Has a History of Recurrent Pneumococcal Pneumonia,Pneumocystis

question 7

Multiple Choice

A 5-year-old boy has a history of recurrent pneumococcal pneumonia,Pneumocystis carinii pneumonia (PCP) ,and bacterial ear infections.His maternal uncle and an older brother experienced the same symptoms,but he has an older sister who is healthy.Laboratory studies indicate normal numbers of B cells and T cells,and the serum contains mostly IgM and very little IgG.Which of the following abnormalities would NOT be likely in this patient?

• A)The IgG antibodies that are present are of lower affinity for antigen than of those of a healthy individual.
• B)Lymph nodes are without well-developed follicles containing germinal centers.
• C)Macrophage killing of intracellular microbes is impaired.
• D)There is limited diversity in the repertoire of IgM antibodies produceD.
• E)There is no evidence of somatic mutation of IgM variable regions.

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Definitions:

Economic Profit

The measure of difference between total financial returns and comprehensive charges, taking into both explicit and silent costs.

Market Price

The existing price point for transactions involving an asset or service in the market.

Perfectly Competitive

A market structure characterized by a large number of small firms, a homogeneous product, and free entry and exit, leading to price taking behavior.

Marginal Revenue

The increase in revenue that results from selling one more unit of a product.