Understanding the salinity of aquatic environment is important in understanding the overall ecosystem because concentration of salt in an aquatic water body will decide which plant or animal species can survive. Some of the species cannot tolerate fluctuations in salt concentrations in aquatic ecosystem and therefore, their population decline. But some species adapt to high or low salt concentrations in water body.
<span>Similarities among the chloroplasts and cyanobacteria.
This is because chloroplasts were once photosynthesizing bacteria that joined up with algae and formed a symbiotic relationship and have stayed in algae since the union.</span>