If a bacterium cannot use citrate agar will not change its color (stays green). On the other hand, if bacteria have the ability to use citrate, the medium will change its color from green to blue.
This happens because citrate agar contains pH indicator such as bromothymol blue which transforms from green to blue in alkaline conditions.
Answer:
B.
Organisms use some of the energy they take in for life process... Like respiration, thermoragulation, etc
<span><u>How does fossilized carbon get back into the atmosphere?</u>
</span>Fossilized carbon is coal. One major way it gets back into the atmosphere is by humans burning it in coal power plants. Carbon gets back into the atmosphere as carbon dioxide through the combustion of fossil fuels.
<span><span><u>How does a plant get nitrogen from the soil?</u>
</span></span>Plants take nitrogen from the soil<span> by absorption through their roots as amino acids, nitrate ions, nitrite ions, or ammonium ions.</span><span>
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It was proposed in 465BC.