Hematocrit and Blood Composition Lecture

Vocabulary terms and definitions covering hematocrit measurement, clinical conditions like anemia and polycythemia, and the hormonal regulation of red blood cells.

Erythrocytes

Also known as red blood cells, they provide for the oxygen carrying capacity of the blood through hemoglobin.

Hemoglobin

The iron containing molecule in red blood cells responsible for oxygen transport.

Hematocrit

The percentage of red blood cells that occupy a volume of whole blood.

Buffy coat

A layer containing leukocytes and platelets that is sandwiched between the plasma and the red blood cells after centrifugation.

Normal range for males

A hematocrit range of $42 \%$ to $52 \%$ (or $47 \pm 5 \%$).

Normal range for females

A hematocrit range of $37 \%$ to $47 \%$ (or $42 \pm 5 \%$).

Anemia

A condition where the oxygen carrying capacity of the blood is too low to support normal metabolism, often caused by a low hematocrit.

Polycythemia

An abnormal condition characterized by having too many red blood cells (too high a hematocrit).

Erythropoietin (EPO)

A hormone produced by the kidneys that stimulates the red bone marrow to increase erythropoiesis (erythrocyte synthesis).

Hypoxia

A lower than normal level of oxygen delivery to the tissues which acts as the direct stimulus for EPO release.

Testosterone

A male sex hormone that enhances the kidney's production of EPO, contributing to higher male hematocrit ranges.

Secondary polycythemia

A condition where individuals at higher altitudes develop an elevated hematocrit due to lower oxygen content in the air.

Blood doping

A practice used by athletes to improve performance by artificially increasing the oxygen carrying capacity of their blood.