Microbiology Practice Exam

Which of the following white blood cells helps mediate allergic reactions?

1. Neutrophil

2. Basophil

3. Monocyte

4. Eosinophil

The correct answer is: Basophil

Basophils play a key role in mediating allergic reactions due to their ability to release histamine and other chemicals when activated. They contain granules that store these mediators, which are released in response to allergens. This release leads to classic allergic symptoms such as swelling, inflammation, and the contraction of smooth muscles. Basophils are crucial in the early stages of an allergic response, contributing to the overall inflammatory process by attracting other immune cells to the site of the allergen. Other white blood cells listed, such as neutrophils, monocytes, and eosinophils, serve different functions. Neutrophils primarily respond to bacterial infections and are involved in the acute inflammatory response. Monocytes differentiate into macrophages and dendritic cells in tissues, playing a significant role in phagocytosis and presenting antigens to T cells. Eosinophils are notably involved in combating parasitic infections and also play a role in allergic reactions, particularly in later phases, but basophils are more directly responsible for initiating the allergic response.