Answer:
Using the real system might mess up and using a computer model is clearer and gives a more advanced view
1. Atmosphere
2.terrestial biosphere
3. Ocean
Answer:
1.) stromatolites
2.) photosynthesis
3.) Ordovician
4.) Cambrian
5.) oxygen
6.) As Earth cooled, carbon dioxide dissolved in the early ocean. Cyanobacteria consumed carbon dioxide and converted it to oxygen. Methane was removed from the atmosphere as oxygen was produced, eventually leading to the Cambrian Explosion.
7.) Metabolic processes that use oxygen produce more energy than anaerobic metabolism. Simple diffusion of oxygen would limit the size of a multicellular eukaryote, but animals evolved ways to transport oxygen to their tissues, which permitted an increase in size.
Explanation:
From Penn
The answer is the second and third answers. Kingdom Protista is a polyphyletic taxon, meaning they did not evolve from one common ancestor, unlike what you see from a monophyletic taxon. Because they come from multiple ancestors, they share more similarities with other organisms from other kingdoms, rather than themselves.