B. tears , this is not a first line of defense
Answer: facilitate the transport of substances across a cell membrane.
Explanation:
1. During inhalation the diaphragm contracts or moves down, what happen to the chest
cavity?
a. Expand
Answer:
The heart pumps blood through the lungs. In the lungs the blood receives oxygen and releases carbon dioxide. Then the heart pumps this oxygen-rich blood from the lungs to your cells. When the oxygen-rich blood gets to the cells, the cells receive the oxygen and release the carbon dioxide.
The cells in our bodies need oxygen to stay alive. Carbon dioxide is made in our bodies as cells do their jobs. The lungs and respiratory system allow oxygen in the air to be taken into the body, while also letting the body get rid of carbon dioxide in the air breathed out.
Explanation:
Hopefully this helps :)
Answer:
Explanation:a
majority of an atom's mass is found its protons and neutrons, subtracting the number of protons (i.e. the atomic number) from the atomic mass will give you the calculated number of neutrons