2,3-Bisphosphoglyceric acid
2,3-Bisphosphoglyceric acid (2,3-BPG), also known as 2,3-diphosphoglyceric acid (2,3-DPG), is a three-carbon isomer of the glycolytic intermediate 1,3-bisphosphoglyceric acid (1,3-BPG).
Image: Fetal hemoglobin chart
Hemoglobin is a protein containing iron that facilitates the transport of oxygen in red blood cells. Almost all vertebrates contain hemoglobin, with the exception of the fish family Channichthyidae. Hemoglobin in the blood carries oxygen from the respiratory organs to the other tissues of the body, where it releases the oxygen to enable aerobic respiration which powers the animal's metabolism. A healthy human has 12 to 20 grams of hemoglobin in every 100 mL of blood. Hemoglobin is a metalloprotein, a chromoprotein, and globulin.
A hemoglobin concentration measurement being administered before a blood donation at the American Red Cross Boston Blood Donation Center.
The giant tube worm Riftia pachyptila showing red hemoglobin-containing plumes
Heart of Steel (Hemoglobin) (2005) by Julian Voss-Andreae. The images show the 5-foot (1.5 m) tall sculpture right after installation, after 10 days, and after several months of exposure to the elements.