Food is pushed through the digestive tract by muscle contractions called
<span>peristalsis.</span>
In the lungs, oxygen is put into the blood and carbon dioxide is taken out of the blood during the process of breathing. After the blood gets oxygen in the lungs, it is called oxygen-rich blood.
You can't see them without a microscope, nor can you smell or taste them individually.
Well, if it's possible to pick more than one, I would say "she should take the appropriate steps if she wishes to avoid pregnancy" and "she should take precautions to ensure that she does not contract and STI"
