Bio-topics

Chordates are animal possess notochord ,dorsal hollow nerve cord and pharyngeal gill slits at any stage of life. They show following features- • They have vertebral column and internal skeleton. • They have bilateral symmetry and are triploblastic. • They have coelomic cavity. • Their body is differentiated into tissues and organs. • Their body consists   head, neck, trunk  and tail. • They have two pairs of fins or limbs. • The respiration in aquatic forms is by gills and in land  forms respiration is by lungs.     features of Chordates Chordates are classified in  "Pisces  ,Amphibians ,Reptilia ,Aves & Mammal.                                                                                   ...

Animals show following features- Body is spiny,  bilaterally symmetrical ,triploblastic,coelomate and "Pentaradiate (five rayed)". Digestion system is complete . Water vascular system is present and helps in  respiration and transportation in body. Tube feet help  in locomotion. Excretion takes place through body surface. Sexual reproduction is seen. Ex- Star-fish ,Sea- Urchin etc. Star-Fish Star-Fish (Anatomy)

Animals show following features- Body is bilaterally symmetrical ,triploblastic and with coelom . Body is soft and mostly enclosed in hard shell. Body is divided into head,foot and visceral mass. Muscular foot helps in locomotion. Digestion system is complete. Open circulation system is found. Respiration takes place through body surface or skin. Excretion takes place by metanephredia. Animals are hermaphrodite.  Example - Snail ,Unio,Octopus etc. Octopus  Snail Unio

Animals related to this phylum show features as-  Body is bilaterally symmetrical,triploblastic and with coelom. Body is divided in three parts i.e. head , thorax and abdomen. Body has jointed legs . Body is exoskeleton made of chitin. Digestive system is complete with a mouth and anus. Respiratory organs are “tracheae”. Eyes are compound. Antennae are tactile organs. Body cavity is called as “ hemocoel ”. Open circulatory system is present. Heart is dorsally placed. Sexes are separate . Larval stage is seen in life cycle.  Examples- Insects (Fly,Mosquito,Bedbug, etc ) Scorpion,Crab,Spider etc. Cockroach Prwan Some Arthropods

Features of animals related to this phylum are as - Body is triploblastic and bilaterally symmetrical. Body is   metamerically segmented. Body cavity is   coelom layered by mesoderm. Locomotion takes place by setae (in Earthworm ) and parapodia (In Nereis ). Digestive system is complete with mouth and anus. Gas exchange takes place through body wall. Circulation system is closed. Excretion takes place by “nephridia”. Some anneilids like Nereis are unisexual while some annelids like   Earthworm and Leech are hermaphrodite. Sexual reproduction is seen. Examples- Nereis ,Leeches and Earthworms. Earthworm Leech   Nereis

Animals are marine, fresh water or terrestrial parasitic worm. Body is cylindrical, bilaterally symmetrical and covered by cuticle covering. Body show adaptations for parasitic mode of life. Body –cavity is pseudocoel. Digestive system is complete with mouth and anus. Respiration takes place by gaseous exchange. Circulatory system is absent. Sexual reproduction is found.  Sexes are separate. Internal fertilization occurs. Ex- Ascaris  etc. Ascaris Male & Female

This phylum includes “flat animals”. Animals are aquatic (fresh water or marine) or terrestrial free-living or parasitic. Body is bilaterally symmetrical, triplobastic and dorsoventrally flat. Digestive system is incomplete and without anus. Other systems are absent. Excretion takes place  with the help of  flame cell or protonephridia. Animals are hermaphrodite and sexual reproduction takes place.      Ex- Flat-worm, Tape-worm etc. Liver-Fluke Tape-worm