Final answer:
The cell utilizes phagocytosis to degrade and expel bacteria by engulfing them in a phagosome which fuses with a lysosome, destroying the bacterium with digestive enzymes. bacteria such as Mycobacterium tuberculosis are capable of developing resistance to this process.
Step-by-step explanation:
How Cells Utilize Phagocytosis: Cells employ phagocytosis to degrade and expel bacteria in a multi-step process. First, the cell extends a portion of its plasma membrane to form pseudopodia, which envelop the bacteria. This engulfed bacterium is then sealed within a vesicle known as a phagosome. The phagosome fuses with a lysosome to form a phagolysosome where digestive enzymes and acids destroy the bacterium. The next step involves proteases that process bacterial antigens, presenting the most antigenic epitopes on the cell's surface with major histocompatibility complex (MHC) II molecules.
Thus, T cells are activated upon recognizing these antigens. Finally, the cell expels the residual debris of the digested bacterium via exocytosis.Resistance in BacteriaHowever, certain bacteria, such as Mycobacterium tuberculosis, Listeria monocytogenes, and Shigella, have mechanisms to resist phagocytosis. These bacteria can prevent the fusion of the phagosome and lysosome or escape into the cytoplasm, evading destruction and allowing them to survive and multiply within the host cells.