The main organ of the respiratory system is the lungs.
The correct answer is C. The constituents in food that the body requires to function properly.
Explanation:
In health, nutrients are substances found in food that are essential for life and different functions in living organisms such as grow, reproduce, or develop. These substances are needed in different amounts by humans, which is defined by the recommended daily intake; for example, everyday individuals should eat between 45 to 75 grams of fat. Moreover, nutrients are classified into big groups that include fats, minerals, proteins, vitamins, and carbohydrates. According to this, nutrients are "the constituents in food that the body requires to function properly."
Answer:
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:
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