Answer: d
The respiratory and circulatory systems bring oxygen and nutrients to the cells. The respiratory and circulatory systems work together to maintain homeostasis. The respiratory system moves gases into and out of the blood. The lungs contain the bronchi, bronchioles, and alveoli.
Explanation:
The function of the respiratory and circulatory systems is that they continuously supply body tissues and cells with oxygen.
The respiratory system is made up of the tissues and the organs that help people breathe e.g. lungs.
The circulatory system helps in transporting nutrients and blood in the body.
The respiratory and the circulatory system is essential for the body to function well.
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