A variety of hæmatin forming the colouring matter or pigments of the urine.

a substance, typically a protein with a prosthetic group (such as haem) containing one or more metal atoms, which transports oxygen within blood…

The colouring matter of the fæces.

The oxidized form of a luciferin produced by the action of a luciferase.

wear-and tear-pigment (Biochemistry): a pigment that accumulates in cells as they age.

a pigment (e.g. in the eye) which is chemically responsive to light.

Any of a class of light-sensitive pigments found in the retinas of freshwater vertebrates, analogous to rhodopsin in humans but differing from it in…

A red-sensitive pigment present in the cones of the retina. Cf. chlorolabe, n., cyanolabe, n.

Any of a group of blue-sensitive photopigments (flavoproteins) which are involved in mediating circadian and seasonal activity in plants; (also) any…