Blood is the primary medium of transportation in most animals, especially vertebrates. It circulates through blood vessels, transporting essential materials such as oxygen, nutrients, hormones, and waste products to and from various body cells.

Latex and cell sap are media of transportation found exclusively in plants. Latex is stored in specific plant cells, while cell sap is a solution found in the plant cell vacuole and is involved in the transport of water and dissolved minerals and food.

Cytoplasm is the internal fluid of a cell and is responsible for intracellular transport (movement of materials within a single cell), primarily in lower unicellular organisms like the amoeba. In complex, multicellular animal organisms, specialized transport systems like blood are necessary due to the large distances materials need to move.