Which cell type is among the first responders to bacterial infection, performing phagocytosis?

Which cell type is among the first responders to bacterial infection, performing phagocytosis?

• A. Neutrophils
• B. Erythrocytes
• C. Platelets
• D. Basophils

Answer: (A)

Neutrophils are the body's first responders to bacterial invasion. These white blood cells act quickly as part of the innate immune system, rushing to the infection site in response to chemical signals. Once there, they perform phagocytosis, engulfing bacteria and destroying them inside a phagosome that fuses with lysosomes. The respiratory burst then releases reactive oxygen species and enzymes that kill the captured microbes. Because of their rapid arrival and strong bactericidal activity, neutrophils are the primary cells responsible for initial bacterial clearance and often contribute to pus as they die after fighting infection. Erythrocytes don’t engage in phagocytosis, as their main role is oxygen transport. Platelets are tasked with clotting and wound repair, not eating bacteria. Basophils participate in inflammatory signaling and allergic responses rather than phagocytosis.

Neutrophils are the body's first responders to bacterial invasion. These white blood cells act quickly as part of the innate immune system, rushing to the infection site in response to chemical signals. Once there, they perform phagocytosis, engulfing bacteria and destroying them inside a phagosome that fuses with lysosomes. The respiratory burst then releases reactive oxygen species and enzymes that kill the captured microbes. Because of their rapid arrival and strong bactericidal activity, neutrophils are the primary cells responsible for initial bacterial clearance and often contribute to pus as they die after fighting infection.

Erythrocytes don’t engage in phagocytosis, as their main role is oxygen transport. Platelets are tasked with clotting and wound repair, not eating bacteria. Basophils participate in inflammatory signaling and allergic responses rather than phagocytosis.