Natural selection occurs to give help the best survival chance to the organisms.
While a constant supply of freshwater happens by itself in natural streams, an aquarium is by definition, a closed system. So here, man has to help out in order to provide new..
Answer:
Dissolved oxygen concentrations are constantly affected by diffusion and aeration, photosynthesis, respiration and decomposition. While water equilibrates toward 100% air saturation, dissolved oxygen levels will also fluctuate with temperature, salinity and pressure changes ³.
Relationship between oxygen uptake and dissolved oxygen concentration The potential for adverse effects of low DO concentrations on fish can be defined ...
Explanation:
The answer is true because you cant live without water