When we breathe in, oxygen enters our lungs and enters small sacs in our lungs called the alveoli. In the alveoli, the oxygen diffuses INTO the bloodstream through small blood vessels, called capillaries, that surround these alveoli. The oxygen is now in our bloodstream instead of our lungs and is used in cell respiration etc.
Oppositely, carbon dioxide is diffused FROM the bloodstream TO the alveoli, also through these capillaries. The carbon dioxide is now in the lungs instead of the bloodstream and when you breathe out, the carbon dioxide is breathed out out of your lungs.
Hope this helped, even if it helped a tiny bit. :)
Conclusion this is how the nervous system in human
Answer:
When it needs water it will release oxygen into the atmosphere. That makes more room for water and it can suck it up.
Explanation:
1. All living things are made of cells.
2. The purpose of the cell is to organize.
3. Cells are made of organelles
4. Cells are made of proteins.
5. There are many many cells in a living thing.