This system processes food, breaking it down into nutrients small enough to travel through the blood to all cells. Group of answer choices Excretory System Circulatory System Nervous System Digestive System Respiratory System

The circulatory and respiratory systems work together to circulate blood and oxygen throughout the body. Air moves in and out of the lungs through the trachea, bronchi, and bronchioles. Blood moves in and out of the lungs through the pulmonary arteries and veins that connect to the heart.

Explanation:

Basically both the respiratory and circulatory work together to help circulate blood in a 'safe speed' and to go through the right passages in your body without getting in the wrong places which can cause horrible injures.

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