The cells are producing carbon dioxide and water. By taking in oxygen, the one performing cellular respiration releases carbon dioxide into the air.
Answer:
A. Food was turned into blood, and when it reached the heart it was mixed with air to make 'spirit.'
Explanation:
Galen believed a theory of pneuma. That is, he believed that blood contains "vital spirits" released into it by the brain.
The answer is A. Hope this helps you out.
To answer your question the name of this process is, Natural Selection.
