Answer:
The smallest bronchioles end in tiny air sacs, called alveoli. They inflate when a person inhales and deflate when a person exhales. During gas exchange oxygen moves from the lungs to the bloodstream.
Explanation:
Answer:
the first one
Explanation:
i think it's more reasonable
During exercise, an individual's heart rate tends to increase steadily until a level of consistent intensity has been reached. Correct answer:C Afterwards the heart rate decreases back to normal.
As a result of increased exercisethe volume of blood pumped by the heart increases
