Aquatic ecosystems are governed by factors such as amount of oxygen, amount of light, and water movement.
a. true
b. false

False

Marine ecosystems like lakes and oceans have aphotic zones. Aphotic zones refer to the zones in the water where there is little or no sunlight. It is found in bodies of water were depths only receive less than 1% of sunlight penetrations. Bioluminescence is essentially the only light found in this zone and most food comes from dead organisms that sink at the bottom of lakes or oceans. 

Ribonuclease activity is a type of nuclease that catalyzes the degradation of rna into small components.

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