Active transport

Unidirectional----substance are transported in one direction only
Carrier protein

For large particles
Phagocytosis

1. Invagination of the cell membrane/pseudopodia surround foreign particles
2. Cup-shaped cavity pinched off from cell membrane, it forms phagocytic vesicles/food vacuole
   
3. Vesicle migrates to the center of the cell
4. Lysosome fuses with the vesicle
5. Hydrolytic enzymes are discharged from lysosome to vesicle for digestion
6. Digested products are absorbed by the cytoplasm
7. Vesicle containing indigested matter moves towards the edge of the cell
8. Indigested matter removed when vesicle fused with the cell membrane

Pinocytosis
Similar to phagocytosis but differs in

1. liquids instead of solid are digested
2. pinocytic vesicles are much smaller than phagocytic vesicles