Its the study of living organisms.
Answer:
Single celled organisms
Explanation: belonging to the domains Bacteria and Archaea. Prokaryotic cells are much smaller than eukaryotic cells, have no nucelus, and lack organelles. All prokaryotic cells are encased by a cell wall. Many also have a capsule or slime layer made of polysaccharide.
Geosphere refer to the portion of the Earth system that include Earth's interior, rocks, and minerals
And hydrosphere refer to all the water on earth surface.
These two spheres often interact with each other in the water cycle
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