The following are steps in phagocytosis: (1) Bacterium is digested by lysosomal enzymes; (2) phagocyte approaches bacterium; (3) phagocytic vesicle fuses with lysosome; and (4) phagocyte engulfs bacterium, forming a phagocytic vesicle. In which order do these steps occur?

2, 4, 3 and 1

Explanation: option 2: phagocyte approaches bacterium. The phagocyte is attracted to the bacterium.

Option 4: phagocyte engulfs bacterium, forming a phagocytic vesicle. The bacterium is engulfed by the phagocytes leading to the formation of a food vesicle.

Option 3: phagocytic vesicle fuses with lysosome. Lysosomes in the phagocytes fuses to the vesicle formed and;

Option 1: Bacterium is digested by lysosomal enzymes. The lysosomes secret enzymes that with digest the bacterium.