Final answer:
True. The binding of microbes to phagocytic receptors initiates phagocytosis, which is a key defense strategy of the innate immune system involving cells like neutrophils and macrophages. This process is often mediated by antibodies and complement proteins that tag pathogens for destruction.
Step-by-step explanation:
The binding of microbes to phagocytic receptors does indeed initiate phagocytosis. When cells of the innate immune system, such as neutrophils and macrophages, encounter a pathogen with foreign antigens on its surface, they will bind to these antigens. This process is often mediated by antibodies, which function by binding to antigens on the surface of pathogenic bacteria, tagging them for phagocytosis. Phagocytes have receptors that can directly recognize bacterial components or can bind to opsonized pathogens (those coated with antibodies or complement proteins), thereby facilitating their uptake and destruction.
For example, neutrophils are a type of phagocyte that binds to Pathogen-Associated Molecular Patterns (PAMPs) on bacteria, triggering uptake and destruction. This is known as Pattern Recognition Receptors (PRRs) binding to PAMPs. After phagocytosis, a phagolysosome is typically formed to digest the pathogen. However, some bacteria have mechanisms to avoid this destruction, such as inhibiting phagolysosome formation.
In summary, the answer to the student's question is: (a) True. The binding of microbe to phagocytic receptors initiates phagocytosis.