Copper-based oxygen-transport pigment in some invertebrates is which?

Copper-based oxygen-transport pigment in some invertebrates is which?

• A. Hemerythrin
• B. Hemocyanin
• C. Myoglobin
• D. Hemoglobin

Answer: (B)

Copper-based oxygen-transport pigment in some invertebrates is hemocyanin. This protein carries oxygen in the animal’s hemolymph using copper ions at its active sites to bind O2, and when oxygenated it has a characteristic blue color. This contrasts with iron-based systems used in vertebrates, where hemoglobin (and the related myoglobin for storage in muscle) rely on iron in a heme group to bind oxygen. Hemerythrin, another invertebrate oxygen carrier, uses iron but not within a heme and has a different color, often violet-pink. So the copper-containing pigment used by many invertebrates to transport oxygen is hemocyanin.

Copper-based oxygen-transport pigment in some invertebrates is hemocyanin. This protein carries oxygen in the animal’s hemolymph using copper ions at its active sites to bind O2, and when oxygenated it has a characteristic blue color. This contrasts with iron-based systems used in vertebrates, where hemoglobin (and the related myoglobin for storage in muscle) rely on iron in a heme group to bind oxygen. Hemerythrin, another invertebrate oxygen carrier, uses iron but not within a heme and has a different color, often violet-pink. So the copper-containing pigment used by many invertebrates to transport oxygen is hemocyanin.