A dog breathes in oxygen and then releases carbon dioxide when he exhales. Conversely, a tree gives off oxygen and takes in carbon dioxide. So the breath of the dog sustains the tree while the output of oxygen for the tree sustains the dog.
Answer:
d
Explanation:
Your heart is an organ that’s largely made up of muscle. It has the vital function of working to pump blood to the organs and tissues of your body.
Rain forest contains more species
