Consider the concentration gradients of oxygen and carbon dioxide to determine t
ID: 65315 • Letter: C
Question
Consider the concentration gradients of oxygen and carbon dioxide to determine their direction of movement at the alveoli of the lungs.
Select the true statement.
Oxygen moves down its concentration gradient from the lungs to the blood. Carbon dioxide moves down its concentration gradient from the lungs to the blood.
Oxygen moves down its concentration gradient from the lungs to the blood. Carbon dioxide moves down its concentration gradient from the blood to the lungs.
Oxygen moves down its concentration gradient from the blood to the lungs. Carbon dioxide moves down its concentration gradient from the lungs to the blood.
Oxygen moves up its concentration gradient from the lungs to the blood. Carbon dioxide moves up its concentration gradient from the lungs to the blood.
Oxygen moves up its concentration gradient from the lungs to the blood. Carbon dioxide moves up its concentration gradient from the blood to the lungs.
Explanation / Answer
Consider the concentration gradients of oxygen and carbon dioxide to determine their direction of movement at the alveoli of the lungs……………….. The correct statement is ...................Oxygen moves up its concentration gradient from the lungs to the blood. Carbon dioxide moves up its concentration gradient from the blood to the lungs. Blood arriving to lungs has much CO2 concentration i.e. blood has higher concentration gradient of CO2 than lungs. However air in the alveoli has lower CO2 concentration. This concentration gradient helps in diffusion blood CO2 to alveolar air by diffusion. During respiration, the lungs has lower O2 and higher CO2 inside. The alveoli of lungs has more oxygen compared to blood, that is higher concentration gradient of O2 in lungs than blood and blood has higher CO2 than lungs. With fresh blood, the O2 moves into blood stream from lungs decreasing their concentration gradient in the lungs. At the same time red blood cells down their concentration gradient to diffuse CO2 into lungs.