Oxygen and Carbon Dioxide Physiology

Flashcards covering vocabulary terms and definitions related to oxygen and carbon dioxide physiology.

Oxygen (O2)

A colorless, odorless reactive gas that comprises about 20.95% of the earth’s atmosphere. Essential to life.

Henry’s law of solubility

The amount of oxygen that dissolves into the plasma is directly proportional to the partial pressure of oxygen in the alveoli at a given temperature.

Hemoglobin (Hb)

Protein in erythrocytes made up of four polypeptide chains, each containing an iron atom bound to a heme group.

Oxyhemoglobin

Hemoglobin bound with oxygen.

Deoxyhemoglobin

Hemoglobin not bound by oxygen; also called reduced or unsaturated hemoglobin.

Oxyhemoglobin Dissociation Curve

A graphic representation of the oxygen saturation of hemoglobin (SO2) and the partial pressure of oxygen in the blood (PO2).

Hemoglobin-oxygen affinity

The ability of oxygen and hemoglobin to bind to one another.

P50

The point at which hemoglobin is 50% saturated with oxygen.

Bohr Effect

States that the affinity of hemoglobin for oxygen decreases and favors dissociation of oxyhemoglobin as the partial pressure of carbon dioxide increases.

Haldane Effect

Explains the affinity for oxygen and carbon dioxide to hemoglobin; hemoglobin molecules have a greater affinity for carbon dioxide in the absence of oxygen.

Anemia

A condition in which an abnormally low level of hemoglobin and/or low hematocrit is identified in the blood.

Polycythemia (Erythrocytosis)

An abnormal elevation in the amount of hemoglobin in the blood or the hematocrit.

Cyanosis

A bluish-gray tint to the skin and or mucous membranes that occurs when blood oxygen levels drop.

Hypoxemia

A low level of oxygen in the blood (PaO2).

Hypoxia

A low level of oxygen in the tissues.

Total oxygen delivery (DO2)

A calculation of the total amount of oxygen being delivered to the tissues; includes both the oxygen dissolved in the plasma and the oxygen bound to the hemoglobin

Oxygen Consumption

A calculation of the amount of oxygen being used by the tissues.

Oxygen Extraction Ratio (ER)

The ratio of oxygen consumption to oxygen delivery.

Carbon Monoxide (CO)

Poisonous, odorless, colorless gas that is a by- product of the incomplete burning of materials containing carbon.

Carboxyhemoglobin (COHb)

Compound formed when carbon monoxide binds with hemoglobin, preventing oxygen from binding.

Carbon Dioxide (CO2)

Composed of a carbon atom covalently double bonded to two oxygen atoms; transported to the lungs for elimination via the plasma and by the erythrocytes.

Bicarbonate Buffer System

Conversion of carbon dioxide to bicarbonate and bicarbonate conversion back to carbon dioxide.

Carbon Dioxide Dissociation Curve

Describes the relationship between PCO2 and the total carbon dioxide concentration in the blood.