Which statement about hemoglobin is true?

Question

Quizplus · Accepted Answer

The cytoplasm of erythrocytes contains hemoglobin, a red, complex protein made of four chains of amino acids called globins. Each chain contains a heme group with an iron ion at its center that can bind to one oxygen molecule. So, each hemoglobin molecule can carry four oxygen molecules. There are approximately 280 million hemoglobin molecules dissolved in the cytoplasm of each erythrocyte. This makes the cytoplasm of a red blood cell a 33% solution of hemoglobin.

Which Statement About Hemoglobin Is True