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 through the screens and settling tanks. They remove the solid and organic matter along with ...

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 system. The nervous system is ring shape and lies around the front part of alimentary ...

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 in flat worms. The excretory system is unique in round worms which contains canals and ...

Respiration is mainly of two types that are aerobic and anaerobic. Aerobic respiration includes cutaneous, branchial and body surface respiration. Aerobic animals require oxygen which is utilized from air or water. Organisms like Hydra show body surface respiration. These are aquatic animals. Animals like fishes, ...

Digestive tract is defined as the path through which food travels and goes through the various processes like absorption, digestion and elimination. Animals included under coelenterates and flat worms have single opening for ingestion and egestion. This single opening is known as mouth. This type ...

The kingdom animal consists of multi cellular eukaryotic organisms. It consists of many phyla which are mentioned below. Phylum Porifera are pore bearing animals. Phylum Cnidaria has stinging cells and coelenterons with single opening. Flatworms come under Phylum Platyhelminths. Round worms and segmented worms are included ...