What happens if the magnesium cycle stops is altered in any way

How did the research presented in the article affect scientists' understanding of the evolution of eukaryotes

What are the two causes of density in deep current waters? a. salinity (how much salt) of the water and high temperaturesb. salinity (how much salt) of the water and low temperatures c. oxygen content of the water and high temperatures. d. oxygen content of the water and low temperatures

Which could be a pathway of food through an ecosystem