iron
The iron containing part of hemoglobin is the 'heme' molecule.
A portion of the heme group
Hemoglobin contains a heme group with an Iron ion attached to it. The iron is what binds to O2.
Haemoglobin is found in red blood cells in the blood. Its function is to carry oxygen to all parts of the body through oxygenated blood.
The porphyrias are disorders in which the body produces too much porphyrin and insufficient heme (an iron-containing nonprotein portion of the hemoglobin molecule).
Nothing
I hate these stupid work sheets they always give you in science classes. but the answer is (IRON)
myosin cross-bridges
The hydrophobic portion of a synthetic detergent molecule usually consists of a series of hydrocarbons. It is attracted to particles of oil and grease.
Cells make up the solid portion which is 45% of the blood. red blood cells, hemoglobin, whiteblood cells, and platelets.
The retina.
A small portion is carried in the blood plasma and the remainder is transported by combining with hemoglobin.