Answer:
notochord, a dorsal hollow nerve cord and pharyngeal slits.
Most heterotrophs are chemoorganoheterotrophs<span> (or simply </span>organotrophs<span>) who utilize organic compounds both as a carbon source and an energy source. The term "heterotroph" very often refers to chemoorganoheterotrophs. Heterotrophs function as consumers in </span>food chains: they obtain organic carbon by eating autotrophs or other heterotrophs. <span>Most </span>opisthokonts<span> and </span>prokaryotes<span> are heterotrophic</span>
Increased use of antibiotics since the few that are immune will survive and reproduce and will out grow others that arent.
In any ecosystem, there are factors to control populations.
In a stream, the predators of a certain organism will help keep populations checked. Moreover, the limited resources, such as space and food, will keep the population from growing out of control.
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