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Megha Suresh
Currently pursuing my engineeering in Biotechnology, in B.M.S college of Engineering. Dancing & Reading keeps me alive.

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  2. MOLLUSCA The organisms belonging to this group are bilaterally symmetrical. The coelomic cavity is reduced in these organisms There is little segmentation. They have an open circulatory system. They have kidney-like organs for excretion. There is a foot that helps for movement. Examples of animals belonging to this group are Unio Pila snails and mussels, pila, unio.

  3. ECHINODERMATA - The organism that belongs to this group are spiny skinned Feather star Sea cucumber organisms They are free-existing marine animals. - They are triploblastic. - They have a coelomic cavity Sea urchin Star fish These organisms use an irregular water-driven cylindrical system for movement. - They have hard calcium carbonate structures which is their skeleton Examples of organisms belonging to this group are starfish and sea urchins.

  4. PROTOCHORDATES Are generally marine animals. The organisms belonging to this group are bilaterally symmetrical. They are triploblastic and have a coelom. They have a long rod-like support structure called notochord at certain stages during their lives. The notochord is a runs along the back of the animal and separates the nervous tissue from the gut that gives a place for the muscles to attach for an easy and comfortable movement. Examples of organisms belonging to this group are Balanoglossus, Herdmania and Amphioxus

  5. VERTEBRATA - The animals belonging to this group possesses a true vertebral column These organisms have internal skeleton which allows a completely different distribution of muscle attachment points required for movement. Animals belonging to this group are bilaterally symmetrical.

  6. They are triploblastic, coelomic and segmented. They have a notochord, dorsal nerve cord and paired gill pouches. They also have a complex differentiation of body tissues and organs. VERTEBRATES This group of animals can be further divided into following categories: PISCES | | AMPHIBIA REPTILIA | | AVES || MAMMALIA

  7. PISCES The fishes belong to this group - This group contains the aquatic animals. This group of animals has skin covered with scales. They absorb the oxygen dissolved in water by using gills to meet their requirements for their survival. hoy have streamilined body and a muscular tail which helps them to move. - They are cold-blooded.

  8. They have two chambered heart. They lay eggs to give birth to their young ones. - Some aquatic species have a skeletons made entirely of cartilage. For example, sharks. TUNA Whereas some species have a skeleton made of both bone and cartilage. For example, fishes like tuna or rohu.