One of protein function is transporting of other substances. It is specific group of the body’s proteins specialize in moving nutrients and other molecules.
Transport protein regulate the flow of substance (including nutrients) into and out of the cell.
For example, hemoglobin, the iron-containing protein of blood, transport oxygen from the lungs to other parts of the body. Other proteins transport molecules across cell membranes.
Transport proteins may function by acting as carriers or they may provide protein-lined passages (pores) through which water-soluble materials of small molecular weight may diffuse.
There are two different types of transport proteins: those that carry molecules to “distant” locations (within a cell or an organism), and those that serve as gateways carrying molecules across otherwise impermeable membranes.
In order for vast numbers of multicellular to exist, they must have a system for delivering oxygen to all their cells, especially those cells that are not in direct contact with the organisms external; environment.
Hemoglobin is an example of an oxygen transport protein and is part of these oxygen delivery systems.
Other transport proteins move about in the body fluids, carrying nutrients and other molecules from one organ to another. Those that carry lipids in the lipoproteins are examples.
Special proteins also ca carry fat-soluble vitamins, water-soluble vitamins, and minerals.
Therefore, a protein deficiency can cause a vitamin A deficiency or a deficiency of whatever other nutrient needs a transport protein to reach its destination in the body.
Transport Proteins
