A 5-Year-Old Child Is Brought to the Emergency Department by His

question 16

Multiple Choice

A 5-year-old child is brought to the emergency department by his parents for right arm pain.  The patient reports that he was playing hide and seek outside and felt a sharp pain on his arm while hiding in some thick bushes.  His parents suspect that something had stung him.  Physical examination shows an edematous and erythematous plaque with mild central pallor.  A residual stinger, located central to the lesion, is readily extracted.  The physical examination is otherwise not significant.  Which of the following substances is most likely directly responsible for the skin findings observed in this patient?

• A)C3b
• B)IL-2
• C)Histamine
• D)Lysozyme
• E)TNF-α

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Definitions:

Exponential Expression

An expression that involves an exponent, indicating how many times the base is multiplied by itself.

Exponential Expression

A mathematical phrase where numbers or variables are raised to a power or exponent.

Associative Property

A mathematical rule stating that the way in which numbers are grouped in operations does not change their result.

Multiplication

A mathematical operation where a number is added to itself a certain number of times.