A structural protein molecule on the cell surface or within the cytoplasm that binds to a specific factor such as a hormone, antigen or neurotransmitter
Vitamin B12
Vitamin B12 is one of the eight B vitamins; it is a water soluble vitamin and also called cobalamin. It is worth noting that vitamin B12 is the largest and structurally the most complex vitamin. Vitamin B12 deficiency can have serious consequences if it is ignored for long periods of time.
