Transport system that use ATP hydrolysis to drive translocation across the plasma membrane. When used for nutrient uptake, usualyl called ATP-binding cassette transport systems.
Photosynthetic pigments such as carotenoids and phycobiliproteins that aid chlorophyll in trapping light energy.
Cytokines that are chemotactic and chemokinetic for leukocytes. They stimulate cell migration and attract phagocytic cells and lymphocytes.