There are certain organisms which lose the metabolic wastes through their body by diffusion. It includes sponges, coelenterates and echinoderms. There are flame cells which help in excretion and occur…
The nervous system consists of neurons which help in the conduction of impulse and the coordination of body functions. Sponges do not possess it. Coelenterates have primitive type of nervous…
The waste water can be treated mainly by the three stages which involve the primary, secondary and tertiary stage. The primary stage involves the process in which sewage is passed…
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