Animal Kingdom Chordates is for class XI CBSE course.

2. Characteristics:
 Worm-like marine animals.
 Body cylindrical and composed of an
anterior proboscis, a collar and a long
trunk.
 Bilaterally symmetrical, triploblastic and
coelomate.
 Organ-system level of organisation.
 Respiration through gills & open type
circulation.
o Excretory organ proboscis gland.
o Sexes separate, fertilisation external &
indirect development.
 e.g. Balanoglossus and Saccoglossus.
Balanoglossus

3. 1. Presence of a notochord
2. A dorsal hollow nerve chord
3. Paired pharyngeal gill slits
4. Coelomate with organ system level of organisation
5. Post anal tail
IMPOTANT FEATURES OF A CHORDATA :

4. PROTOCHORDATES:
Subphylum Urochordata and Cephalochordata
are called Protochordates.
Phylum Chordata
1. Subphyla Urochordata or
Tunicata
2. Subphyla Cephalochordata
3. Subphyla Vertebrata

5.  Notochord is present
only in larval tail.
 Eg. Ascidia.
 Notochord extends
from head to tail region
and persistent
throughout their life.
 Eg. Branchiostoma
(Amphioxus)
UROCHODATA CEPHALOCHORDATA
PROTOCHORDATES

6.  Notochord persist during embryonic period.
 Notochord is replaced by a cartilaginous or bony
vertebral column in the adult.
 Ventral muscular heart present.
 Kidney for excretion & osmoregulation.
 Paired appendages may be fins or limbs.
 All vertebrates are chordates but all chordates are
not vertebrates.

7. CLASSES OF VERTEBRATA
1. Cylostomata
2. Chondrichthyes
3. Osteichthyes
4. Amphibia
5. Reptilia
6. Aves
7. Mammalia

8. Characteristics:
 Agnatha (Circular mouth without jaws).
 Ectoparasites on some fishes.
 Body is without scales and paired fins.
 Elongated body bearing 6-15 pairs of gill slits for
respiration.
 Cranium and vertebral column cartilaginous.
 Circulation closed type.
 Marine but migrate to fresh water for spawning &
larva after metamorphosis return to ocean
e.g. Petromyzon (Lamprey), Myxine (Hagfish)
CYCLOSTOMATA

9. Characteristics:
 Streamline body, cartilaginous endoskeleton.
Notochord persist throughout life.
Ventral mouth, powerful jaw, teeth are modified
into placoid scales, predaceous.
Gill slits are separate & without operculum.
Cold-blooded (poikilothermous), Heart two
chambers.
Sexes separate, internal fertilisation, many of
them are viviparous.
Torpedo possess electric organs & Trygon
have poison sting

10. Both marine & fresh water fishes with bony
endoskeleton.
Body streamlined & mouth terminal.
Four pairs of gills covered by operculum.
Body covered with cycloid/ctenoid scales.
Air blader regulates buoyancy.
Heart is two chamber, cold-blooded.
Fins are its locomotory organs.
Sexes separate, fertilisation external.
Mostly oviparous, development is direct.

11. Characteristics:
Habitats - Aquatic as well as terrestrial.
Frogs have smooth, moist skin; Toads have rough, dry
skin.
Body divisible into head and trunk.
Two pairs of limbs.
Tympanum represents ear & eyes have eyelids.
Alimentary canal, urinary and reproductive tracts open
into cloaca.
Respiration is by gills, lungs and through skin.
Heart is three chambered (two auricles & one ventricle).
Cold-blooded animals, sexes separate, fertilisation
external.
Oviparous and development is direct or indirect.
Toad

12. Characteristics:
Body is covered by cornified dry skin, epidermal scales.
Habitat - mostly terrestrial.
Creeping or crawling mode of locomotion.
Two pairs of limbs and tympanum represents ear.
Three-chambered heart, but four-chambered in
crocodiles.
 Poikilotherms & sexes are separate.
Snakes and lizards shed their scales as skin cast.
Fertilisation internal, oviparous and development is
direct.
Example : Chameleon (Tree lizard), Calotes (Garden
lizard), Crocodilus (Crocodile), Hemidactylus (Wall lizard) Wall lizard

13.  Warm-blooded (homoiothermous) animals.
 Forelimbs modified into wings & also possess
feathers used in flight, to regulate temperature
and camouflage purposes.
 Hind limbs have scales and modified for
walking, swimming or clasping the tree
branches.
 Possess beak.
 Bones are pneumatic (hollow with air cavities).
 The digestive tract contains crop and gizzard.
 Heart is four chambered.
 Respiration through lungs & air sacs.
 Sexes are separate; oviparous, fertilisation
internal and development is direct.
Indian Sparrow

14.  Presence mammary glands.
 Skin possess hair & homoiothermous.
 Two pairs of limbs adapted for walking,
running, climbing, burrowing, swimming
or flying.
 Different types of teeth are present in the
jaw.
 External ears or pinnae present.
 Heart four chambered, respiration by
lungs.
 Sexes are separate; viviparous;
fertilisation internal & development is
direct.
 Monotremes lay eggs & Marsupials are
pouched mammals.
 e.g. Platypus, Dolphin
MAMMALS
Delphinus (Dolphin)