The unicellular organisms ingest large molecules into their cytoplasm from the external environment without previously digesting them. This process is called___________?

Explanation

Phagocytosis is the engulfment of large solid particles or molecules by extensions of the cell membrane, forming an internal vesicle for digestion. Students may choose diffusion because it also moves substances across membranes, but diffusion does not engulf large particles and requires no vesicle formation.