Well a theory is when a person comes up with something that they believe is to be true, and they work on projects and other things to show their thinking. theories won't always bee correct which helps us humans grow and come up with new ones
In the human respiratory system, gas exchange occurs across the cells of the alveoli. Alveoli or an alveolus is the deepest part of the human respiratory system. This part of the respiratory system is a place where gas exchange between oxygen and carbon dioxide occurs from inhaled air to the blood cells<span>.</span>
Explanation:
the most common gas in the atmosphere is nitrogen and oxygen followed by CO2 etc...
Answer:
The correct answer is option d) nutrients absorption.
Explanation:
The stomach has several important functions. Mechanically digestion involves the contraction of muscles of the stomach and churning of the food to enhance digestion. The secretion of HCl and enzymes is an important role of the stomach for digestion.
Nutrient absorption is a major function of the intestine specifically small intestine for nutrient absorption.
Thus, the correct answer is d) nutrients absorption.
