Anatomy and Physiology II Practice Test

Which immune cells play a significant role in the initial response to infection?

1. B-cells

2. Neutrophils

3. Memory cells

4. Dendritic cells

The correct answer is: Neutrophils

Neutrophils are crucial players in the body’s initial defense against infections, particularly in the innate immune response. When an infection occurs, neutrophils are among the first immune cells to migrate to the site of infection. They are rapid responders, capable of detecting and responding to pathogens within minutes. Neutrophils combat infections primarily through several mechanisms, including phagocytosis, where they engulf and digest pathogens, and the release of enzymes and reactive oxygen species that can kill microbes. Their role is especially pronounced during bacterial infections, making neutrophils essential for the early stages of immune response. Their ability to quickly respond and act upon detecting pathogens is what primarily distinguishes them as a key component of the initial immune response. Other immune cells, such as B-cells, memory cells, and dendritic cells, play additional roles, but their actions typically take place after the initial immune response has been engaged.