C. Since they have to gain that skill.
Answer:
B. Allows for specialized regions with specialized functions
Explanation:
Where the complete digestive system has different specialized regions to perform specialized functions, the gastrovascular cavity is the primary organ of digestion and circulation in two major animal phyla: the Cnidaria (including jellyfish and corals) and Platyhelminthes (flatworms).
Answer:
used more power second time
Explanation:
the nitrogen cycle involves decompisition. and the waste from the animals is then turned into nitrogen.