animal kingdom

• The phylum Mollusca includes snails, clams, oysters, squid, octopuses, and slugs.
• Mollusks have soft bodies with no internal skeleton or hard parts to protect them.
• In sponges, the cells are arranged loosely i.e. they exhibit cellular level of organization.
• coelenterates have tissue level of organization.
• platyhelminthes exhibit organ level of organization.
• platyhelminthes has only a Single opening that serves as mouth and anus.
• circulatory system is of two types: closed system and open system.
• open circulatory system is in which blood is pumped out of the heart and the cells and tissues directly bathe in it.
• closed circulatory system is in which blood is circulated through a series of vessels.
• sponges are mostly asymeitcal.
• when any plane passing through the central axis of the body divides the organism into two identical halves, its called radial symmetry.
• coelenterates, ctenophores, and echinoderms are all examples of radial symmetry.
• arthropoda, mollusca, annelida, nematoda, platyhelminthes, and chordata have bilateral symmetry.
• bilateral symmetry divides the body into two equal sides, with the left and right sides mirroring each other.
• animals in which cells are arranged in embryonic layers are called Diploblastic animals.
• triploblastic animals have three germ layers during development.
• diploblastics include sponges, coelenterates, and cnidarians
• triploblastic animals include arthropoda, mollusca, annelida, platyhelminthes, and chordata.
• the body cavity, which is lined by mesoderm is called coelom.
• Animals possesing coelom are called coelomates.
• Annelids, molluscs, arthropods are some examples of coelomates.
• The body cavity in which mesoderm is found in scattered pouches between the ectoderm and endoderm is called pseudo-coelom.
• the animals that possess pseudocoelom are called pseudocoelomates.
• the animals in which body cavity is absent are called acoelomates.
• Earthworm shows metamaric segmentation and the phenomenon is known as metamerism.
• animals with notochord are called chordates.
• animals which do not have a notochord are called non-chordates.
• Phylum porifera are generally marine and asymmetrical animal. these are multicelluar animals and have cellular level of arganisation
• Ostia are minute pores present in sponges.
• Sponges have a water transport or canal system.