The other element would be Oxygen.
Explanation:
The carbon cycle occurs on Earth. This cycle contains the series of processes by which carbon compounds are inter-converted in the environment. On moons and other heavenly objects there is no life because there is no carbon cycle. Carbon and oxygen are the two gases required for photosynthesis process in plants to make carbon dioxide and then its return to the atmosphere through respiration.
3: B Nervous system. 4: A Sensing and responding to its external environment.
Approximately 1,000 to 30,000 years old
Put a end to aggressively
Increasing predator population
