The longest living WBC is which one of the following
**Core Concept**
The question is testing the knowledge of the lifespan of different types of white blood cells (WBCs) in the human body. White blood cells are an essential part of the immune system, and their lifespan varies depending on the type and function.
**Why the Correct Answer is Right**
The longest living WBC is the plasma cell, which is a type of B lymphocyte that plays a crucial role in the adaptive immune response. Plasma cells are responsible for producing and secreting large amounts of antibodies, which are proteins that help to neutralize or remove pathogens from the body. Plasma cells can live for several months to over a year, making them the longest living WBC.
**Why Each Wrong Option is Incorrect**
* **Option A:** This option is not specified, but typically, neutrophils are the shortest living WBC, with a lifespan of only a few hours to a few days.
* **Option B:** This option is not specified, but typically, eosinophils have a relatively shorter lifespan compared to plasma cells, with an average lifespan of 8-12 hours.
* **Option C:** This option is not specified, but typically, monocytes have a lifespan of 1-3 days, which is shorter than that of plasma cells.
**Clinical Pearl / High-Yield Fact**
It's worth noting that the lifespan of WBCs can be influenced by various factors, including age, health status, and exposure to pathogens. For example, older adults may have a reduced number of plasma cells, making them more susceptible to infections.
**Correct Answer: C. Plasma cells.**