"Water quality" may include the amounts of dissolved oxygen
and the levels of algal growth, pollutants which may be present and the pH level. Water quality effects also which types of organisms can
survive in a body of water.
Shellfish require a high level
of dissolved oxygen and their abundance is an indication of good water quality. Shellfish are sensitive to changes in the ecosystem and they cannot easily escape changes in the water quality. These are one of the reasons why shellfish are good indicators of water quality.
I would say I don't really don't know
Of have in a parasitic attack
In arthropods, such as insects, arachnids and crustaceans, moulting is the shedding of the exoskeleton(which is often called its shell), typically to let the organism grow. ... The new exoskeleton is initially soft but hardens after the moulting of the old exoskeleton.
No mushrooms don't have cloroplast
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