Animal Kingdom

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ÇLÅSSÏFÏÇÅTÏØÑ ØF VËRTËBRÅTÅ

Vertebrata

Division

Agnatha

(lacks jaw)

Gnathostomata

(bears jaw)

Class

Cyclostomata

Super class

Pisces

(bear fins)

Tetrapoda

(bear limbs)

1. Chondrichthyes

2. Osteichthyes

Class

1. Amphibia

2. Reptilia

3. Aves

4. Mammals

ÇLÅSS ÇÝÇLØSTØMÅTÅ

All are ectoparasites on some fishes

Petromyzon

Elongated body without scales and paired

fins

6-15 pairs of gill slits for respiration

Sucking and circular mouth without jaws

(NEET-II 2016)

Cartilaginous

cranium

and

vertebral

column



Circulation is closed type



Marine, but migrate for spawning to

fresh water. After spawning, they die.

Their larvae, after metamorphosis, return

to ocean.

E.g. Petromyzon (Lamprey) and Myxine (Hagfish).