In this animated object, students observe how ATP energy is used to move substances across the cell membrane from an area of lower concentration to an area of higher concentration and when something too large needs to get in or out of a cell.

This animated object illustrates the events leading to the migration of phagocytes into areas of tissue damage and/or bacterial presence. Learners view bacterial cell phagocytosis, its subsequent enzymatic digestion, and exocytosis.