The period during which the presence of stromatolites decline is the Proterzoic period. Stromatolites are widely distributed sedimentary structures consisting of laminated carbonate or silicate rocks, produced over geologic time by the trapping, binding, or the precipitating of sediment by groups of microorganisms, primarily cyanobacteria.
Plant cells are bigger because they have bigger/larger Vacuoles.
These vacuoles hold water and food for the cell its like a storage for the cell.
meat handlers keep brain tissue from coming in contact with other meat.
hope this helps :)
Carbon debt, caused by CO2<span> i know that is one of them </span>
The temperature of the earth
