Answer:
13
Explanation:
it get recycled again when it becomes old
Answer:
Lack of oxygen
Explanation:
There are two mechanisms for energy production (glucose breakdown), aerobic and anaerobic. When adequate amounts of oxygen are present, aerobic mechanism is used. However, when there is insufficient oxygen, such as during exercise, the anaerobic mechanism is used.
The branching point on a cladogram represents a common ancestor. A cladogram is a diagram used in cladistics to show relations among organisms. However it is not an evolutionary tree since it does not show how ancestors are related to descendants, nor does it show how much they have changed.