Question 1: PO2

Answer

In a biological or medical context, PO2 (or PaO2) refers to the Partial Pressure of Oxygen. It is a measurement of the pressure of oxygen dissolved in the blood (most commonly arterial blood). This measurement helps determine how well oxygen is able to move from the airspaces of the lungs into the blood. Normal arterial PO2 ranges typically fall between 75 to 100 mmHg. Lower than normal levels can indicate hypoxemia, potentially caused by lung diseases or other conditions affecting gas exchange.