Final answer:
The PO2 in the systemic capillary during tissue gas exchange typically ranges between 95 to 100 mmHg, allowing oxygen to be delivered to the tissues and used for metabolic processes.
Step-by-step explanation:
The PO2 in the systemic capillaries during tissue gas exchange typically ranges between 95 to 100 mmHg. As blood passes through the systemic capillaries, oxygen is released from the hemoglobin within red blood cells to supply the surrounding tissues. The oxygen is utilized by the cells for aerobic respiration, which generates ATP, the energy currency of the cell. Consequently, the PO2 in the venous blood leaving the tissues and returning to the heart tends to be much lower, approximately 40 mmHg.
The process of tissue gas exchange is critical for the maintenance of metabolic processes in the body. During this exchange, not only is oxygen delivered to the cells, but carbon dioxide (CO2), a metabolic waste product, is removed from the cells and carried back to the lungs for exhalation.
In the systemic capillary during tissue gas exchange, the partial pressure of oxygen (PO2) is lower compared to the alveoli in the lungs. This is because oxygen diffuses from the capillary into the surrounding tissues. However, the exact value of PO2 in the systemic capillary during tissue gas exchange can vary depending on factors such as the metabolic rate of the tissues.