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
Fertilization generally occurs in the fallopian tube.
Igneous rocks are formed when the magma from an erupting volcano eventually cools this rock is extrusive- found on the earth's surface.
<span>The means is unknown. Filoviruses are known for causing hemorrhagic fever in humans. However, once a human is infected, passing the virus from person-to-person is the means by which others become infected. Most especially is the transmission through infected bodily fluids or objects that have been unsterilized and come into contact with those fluids.</span>