An indicator species<span> is an organism whose presence, absence or abundance reflects a specific environmental condition. </span>Indicator species<span> can signal a change in the biological condition of a particular ecosystem, and thus may be used as a proxy to diagnose the health of an ecosystem.
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Axon: the messenger cell that carries the command to contract muscles.
This is a physics question, not biology, but...
f=1/T where f is frequency and T is the period.
f= 1/(1/3)=3
frequency =3 Hz
Combustion of fossil fuels release massive amounts of carbon dioxide
I am sure 100%
Good luck
