PATHOLOGY MCQ
RESPIRATORY SYSTEM
|
Question
[CLICK ON ANY CHOICE TO KNOW THE RIGHT ANSWER]
|
|
|
Higher concentration of carbon dioxide (CO2) and a lower concentration of oxygen (O2)
|
|
|
Higher concentration of oxygen (O2) and a lower concentration of carbon dioxide (CO2)
|
|
|
Either A or B
|
|
|
None of the above
|
Detailed explanation-1: -Carbon dioxide, made by the cells as they do their work, moves out of the cells into the capillaries, where most of it dissolves in the plasma of the blood. Blood rich in carbon dioxide then returns to the heart via the veins.
Detailed explanation-2: -Venules contain blood that is leaving tissues, so it carries carbon dioxide waste away from these tissues, and venules will therefore have the highest concentration of carbon dioxide.
Detailed explanation-3: -The partial pressure of oxygen is high in the alveoli and low in the blood of the pulmonary capillaries. As a result, oxygen diffuses across the respiratory membrane from the alveoli into the blood. In contrast, the partial pressure of carbon dioxide is high in the pulmonary capillaries and low in the alveoli.