Question

White blood cells are an important component of our immune system. One thing they do is consume and destroy bacteria by extending their plasma membrane around the bacterium and bringing it inside the cell in a vesicle. By what process do they engulf the bacterium?

A) receptor-mediated endocytosis

B) pinocytosis

C) transcytosis

D) exocytosis

E) phagocytosis

Answer 1

White blood cells consume and destroy bacteria through a process called phagocytosis, where the cell membrane envelops the bacterium, digests it, and expels waste products.

Step-by-step explanation:

White blood cells, such as neutrophils, engage in a process known as phagocytosis to consume and destroy bacteria. This process begins when a white blood cell encounters a bacterium and extends a portion of its plasma membrane to envelop it. The surrounding plasma membrane then encloses the bacterium, trapping it within a vesicle inside the cell known as a phagosome. The phagosome merges with a lysosome, which contains digestive enzymes and acids that kill and digest the bacterium. The waste products are later expelled from the cell through exocytosis. Therefore, the process by which white blood cells engulf and digest bacteria is referred to as phagocytosis, which is the correct answer to the question, option E).