Answer: The amount of plankton in the river before and after zebra mussels arrive :)
The main groups of unicellular organisms are bacteria<span>, </span>archaea<span>, </span>protozoa<span>, unicellular </span>algae<span>, and unicellular </span>fungi<span>. </span>
Varying environmental factors determine the different traits is the reason why organisms have specific adaptations.
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What is Adaptation?</h3>
This is the process in which organisms undergo certain changes which makes them become more suited to their environment.
Different environmental factors such as cold climate etc which ensures organisms survive through possession of thicker furs etc.
Read more about Adaptation here brainly.com/question/29594
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