I Believe The Answer Is B. Physical Weathering.
The key processes in the fast carbon cycle include: Photosynthesis: the absorption of CO2 from the atmosphere (terrestrial plants) and from oceans (marine plants) to produce organic carbon structures. Respiration: the release of CO2 into the atmosphere, soil and oceans by animals as they exhale.
Answer:
Cells are considered the basic units of life in part because they come in discrete and easily recognizable packages. That's because all cells are surrounded by a structure called the cell membrane — which, much like the walls of a house, serves as a clear boundary between the cell's internal and external environments.
For many species, there are often regional differences in their genes, although most of the time this differences aren't noticeable in their outward appearance.
C.75 of the cell's mass is water
