Biochemistry. Originally: †the substance that imparts a red colour to blood; haem or haemoglobin (obsolete rare). In later use (as a mass noun)…

= haematin, n. 2.

(a) The special form of crystallin, n. or globulin, n. found in the blood-corpuscles. (b) ‘A name given to hæmoglobin when it is obtained in a…

The oxygenated (bright red) form of haemoglobin, present in oxygenated blood.

Any form of haemoglobin in which the iron of the haem groups is in the ferric (Fe3+) rather than the ferrous (Fe2+) state, and so is unable to bind…

Any of various colourless basic polypeptides forming the protein component of haemoglobin, myoglobin, and related molecules.

a yellow powder obtained from egg yolk and supposed to be the precursor of hæmoglobin (Obsolete).

= methaemoglobin, n.

A substance that causes agglutination of red blood cells.

A chelation compound, C34H32O4N4Fe, of ferrous ion and protoporphyrin, obtained on reduction of hæmatin: the red-coloured non-protein constituent of…

a globulin produced by the liver and present in blood, from which hypertensin I may be liberated by renin.

a plasma protein synthesized by the liver, from which angiotensin I is produced by the action of the enzyme renin.