4Sub phylum: UROCHORDATA The Notochord is confined to the tail region of the larva.Notochord is absent in the Adult and they are sessile forms.The free end of the body has two openings, mouth & the atriopore.They are Hermaphroditic animals.Life cycle shows a free swimming Tadpole like larva,Examples : Ascidia, Doliolum, Salpa.
6Sub phylum: HEMICHORDATA Marine organisms.Solitary or colonial forms.The body is soft , vermiform , unsegmented , bilaterally symmetrical and triploblastic.The body is divided in to proboscis, collar and trunk.A projection from pharynx, projecting inside the proboscsis may be considered as notochord.They are ciliary feeders.Sexes are separate.Examples : Balanoglossus, Saccoglossus.
8Sub phylum: CEPHALOCHORDATA They are fish like marine chordata.They persistent notochord extends forward beyond the brain.The Pharynx is large with numerous gills.It is a filter feeders.Muscles , Nephridia and gonads are seperatelly arranged.Examples : Amphioxus.
10Sub phylum: VERTEBRATA [Craniata] The vertebrate body is typically elongated and exhibits bilateral symmetry.Two pairs of appendages are usually present.The central nervous system, made up of a spinal cord that is enlarged and highly differentiated anteriorly to form a brain.Brain is enclosed within a bony skull called the cranium.Contains the main sensory organs of sight, sound, and smell and the mouth.The sub-phylum vertebrata may be classified into 2 groups1. Pisces2. Tetrapoda (comprises Amphibia, Reptiles, Aves and Mammalia)
12PISCESThey Body is streamlined and differenciated in to head, trunk and tail. The Neck is absent.Locomotion is effected by paired fins and unpaired fins.The body is covered by scales.Respiration is performed by gills. Gill slits are 5–7 pairs.They may be naked or covered by an operculum.Two chambered heart.Excretion is performed by mesonepheric kidney.Lateral line sense organs are well developed.Fertilization is either internal or external.Fishes are Poikilothermic.Examples: Shark , Catla.
16AMPHIBIAThese were the first vertebrates to live on land.The body is differentiated in to head and trunk.The body is covered by smooth and slimy skin.The slimy nature is due to the presence of mucous secreting glands.The wide mouth is situated at the tip of the head.Small teeth are present in upper or both jaws.The external nostrils communicates in to the anterior part of the buccal cavity.
17AMPHIBIARespiration is effected by gills, lungs, skin and bucco-pharyngeal region.Three chambered heart.The trunk has a pair of fore limbs and a pair of hind limbs.Fore limbs are smaller than the hind limbs.Sexes are separate.Fertilization is either external or internal.Life cycle shows the larval stage.
21REPTILIAThe Body is covered with an exoskeleton of horny epidermal scales.The body has penta- dactyl limbs. These are adopted for climbing, running and paddling.The endoskeleton is well ossified.Respiration is by lungs.Three chambered heart.( In crocodile it is four chamber )Excretion is effected by meta-nephric kidney.
22REPTILIA Sexes are separate. Male has copulatory organ to transfer the sperms in to cloaca of the female.Fertilization is internal.Eggs are covered with leathery shells.Examples: Lizard, Snakes, Turtles, Tortoise, Alligator, Crocodiles, Sphenodon.
25AVESThere are more than 8600 species of birds distributed all over the world.Aves are warm blooded vertebrates.The body is covered by feathers and feet are covered with scales.The fore limbs are modified as wings and provided with feathers for flight.The bones are spongy, containing air cavities rendering the body light.Three digits are present in the forelimbs and four toes in hind limbs.A horny beak is present.Four chambered heart.Red blood corpuscles are oval and nucleated.
26AVES Excretion is effected by three lobed kidney. Ureters open in to the cloaca. Urine is semi-solid and contains Uricacid.Eyes are powerful and has a specialized structure called Pecten.Sexes are separate. Fertilization is internal.Eggs are provided with large amount of yolk. The egg is covered by a hard calcareous shell.In spite of several advanced features the birds have certain reptilian characters. Hence they are known as Glorified Reptiles.
29MAMMALIA The term Mammalia was given by LINNAEUS. The body is covered with epidermal hairs.The Integument is provided with sweat glands,sebaceous gland and scent glands.The mammary glands are modified integumentary gland.The external ear or the pinna is present in most of the mammals.A muscular diaphragm is present inbetween the thoracic and abdominal cavity.Red Blood Corpuscles are non-nucleated.Four chambered heart.In Brain , cerebral hemisphere are very large and highly convoluted.Presence of corpus callosum.It is a transverse band of nerve fibres connecting the two cerebral hemisphere..
30MAMMALIAThe Arrangement of teeth in the buccal cavity is called dentition.The Dentition is thecodont, heterodont, diphyodont.Testis lie outside the body cavity, enclosed in scrotal sacs.Eggs are small with little or no yolk.Fertilization is internal.Viviparous - - They give birth to alive young ones.Placenta is usually present.
32Examples : Spiny Ant –eater, Duck- billed platypus. MONOTREMATA[Prototheria]These are egg laying mammals found only in Australia and nearby islands.Examples : Spiny Ant –eater, Duck- billed platypus.The Prototheria are primitive mammals exhibiting several reptilian characters and as such form a very interesting connection between reptiles and higher mammals.These are recorded as Living fossils or Unfinished mammals.The Monotremes are not found in India.
33These are popularly called pouched mammals. MARSUPIALIA[Metatheria]These are popularly called pouched mammals.The marsupials are intermediate between the Primitive Monotremes and the higher mammals.The young ones are born in an immature stage and migrate in to the pouch on the mother`s body.Further development is completed in the pouch or marsupium.Example : Kangaroo.
34EUTHERIA OR Placentalia Eggs develop with in the uterus.The developing embryo receives nutrition through maternal blood circulation via placenta.Example: Elephant, Tiger, Man, Bat
35PRIMATES They inhabit chiefly the warmer parts of the world. This group stands first in the animal kingdom in brain development.Most of them are arboreal.Omnivorous.The body is covered with hairs except palm,sole and parts of face.The neck is mobile.The forelimbs are shorter than the hindlimbs.The limbs have five digits and all the digits end in flat nail.The Brain is highly developed.The cerebral hemispheres are convoluted.The eyes are directed forward and the vision is binocular and stereoscopic.Mammae are two and throcic in position.