Cell Transport Important because it allows cells to maintain homeostasis.

Double layer of phospholipids with proteins embedded Function – Active Transport Bulk Transport Structure – Double layer of phospholipids with proteins embedded Function – Protection Regulate movement of materials into and out of membrane “selectively permeable”

Cell does not use energy H → L Types: Diffusion ex: O2 and CO2 Bulk Transport Cell does not use energy H → L Types: Diffusion ex: O2 and CO2 2. Osmosis ex: H2O 3. Facilitated Diffusion ex: glucose Requires carrier protein molecule

Requires carrier protein molecule Ex: “pumps” Na – K pump Active Transport Bulk Transport Cell uses energy L→ H Requires carrier protein molecule Ex: “pumps” Na – K pump

Bulk Transport Molecules are too large Transported in vesicles Types: Active Transport Molecules are too large Transported in vesicles Types: 1. Exocytosis Secretion of proteins 2. Endocytosis Phagocytosis “cell eating” WBC eating bacteria Ameoba feeding Pinocytosis “cell drinking”