Write a list of as many similarities and differences as you can find between marine ecosystems, estuaries, and freshwater ecosystems.

Similarities:

- Marine and freshwater ecosystems are water, covering almost 75 percent of the earth's surface.

-The most pervasive problem affecting both freshwater and marine ecosystems is pollution.

-The process of regulating the osmotic pressure on fluids inside an organism is essential to all freshwater and marine species.

Differences:

- Marine ecosystems are more diverse than freshwater ones.

- In marine or seawater, the salinity level, or the concentration of salt is greater, but freshwater is not totally void of it.

- Only 1% of the whole water body on the earth is freshwater, the other 99% is marine water.

Note- I couldn't come up with ones for estuaries, sorry.  

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