Hemoglobin and Blood Oxygen Transport Worksheet

Model 1: Oxygen Binding to a Single Hemoglobin Molecule Hemoglobin (Hb) is a large molecule consisting of four peptide chain subunits. Each peptide contains a heme group with an iron molecule at the core. Each heme subunit can reversibly bind one oxygen molecule and, interestingly, the bound/unbound state of each of the four hemes affect how easy it is for new oxygen to be bound and bound oxygen to be released. The number of oxygen molecules bound determine hemoglobin saturation, often expressed as 0 to 100%. Saturated Hemoglobin Molecule QUESTIONS: 1. How many oxygen molecules are bound when a hemoglobin molecule is completely saturated? Four oxygen molecules are bounded with a hemoglobin molecule is saturated. 2. How many oxygen molecules are bound when a hemoglobin molecule is 75% saturated? Three oxygen molecules are bounded with a hemoglobin molecule is 75 % saturated. 3. Assuming you started with the molecule in Model 1, how many molecules of oxygen would need to be released in order for the hemoglobin to be 75% saturated? One molecule of oxygen would need to be released in order for the hemoglobin to be 75% saturated.