Final answer:
The incorrect statement is that hemoglobin represents the ratio of red blood cells to total blood volume; hemoglobin is actually a protein responsible for oxygen transport in the blood.
Step-by-step explanation:
The option that inappropriately describes hemoglobin is: B. hemoglobin is the ratio of red blood cells to total blood volume. This statement is incorrect because hemoglobin is not a ratio of cells to blood volume, but rather a protein found within red blood cells that is responsible for transporting oxygen from the lungs to the rest of the body. Hemoglobin contains a component called heme, which includes an iron atom that can bind to oxygen, thereby facilitating oxygen transport in the bloodstream. Each hemoglobin molecule is capable of binding to four oxygen molecules, thus significantly contributing to the oxygen-carrying capacity of the blood. Additionally, hemoglobin also has a role in transporting carbon dioxide from the body's tissues back to the lungs.