Question

how does the respiratory system work directly with the circulatory system?

Explanation:

The respiratory system takes in oxygen and expels carbon - dioxide. Oxygen enters the lungs and diffuses into the blood in the capillaries surrounding the alveoli. The circulatory system then transports this oxygen - rich blood to the body's cells. At the same time, carbon - dioxide, a waste product of cellular respiration, diffuses from the cells into the blood. The blood carries this carbon - dioxide back to the lungs, where it is exhaled by the respiratory system.

Answer:

The respiratory system exchanges gases (oxygen and carbon - dioxide) with the blood in the circulatory system at the alveoli in the lungs. Oxygen diffuses into the blood and is transported by the circulatory system to cells, while carbon - dioxide from cells is carried by the circulatory system to the lungs for exhalation by the respiratory system.