Animal Kingdom

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Polyp & Medusa: 2 types of body forms in cnidarians.

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Polyp

is

tubular

attached

asexual

form, with upwardly directed mouth &

tentacles. E.g. Hydra, Adamsia.

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Medusa is umbrella like, free-swimming

sexual form, with downwardly directed

mouth & tentacles. E.g. Aurelia (Jelly fish).

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Bioluminescence: It is the property of some animals to emit light from

the body. E.g. Pleurobrachia (comb jelly)

Features

Platyhelminthes

(Flatworms)

Aschelminthes

[Roundworms]

Annelida

Arthropoda

Levels of

organisation

Organ

Organ system

Organ system

Organ system

Symmetry

Bilateral

Bilateral

Bilateral

Bilateral

Germ layers

Triploblastic

Triploblastic

Triploblastic

Triploblastic

Coelom

Acoelomate

(NEET 2020)

Pseudocoelomate

Coelomate

Coelomate

Habit and

habitat

Mainly aquatic,

endoparasites,

some are free-

living

Aquatic and

terrestrial, free

living or parasitic

in plants &

animals

Terrestrial,

fresh water

or marine,

free living or

parasitic

Cosmopolitan,

over two third

of all named

species on

earth are

arthropods

Digestive

system

Incomplete

Complete. Tubular

alimentary

canal with

well-developed

muscular pharynx

Complete

Complete

Respiratory

system

Absent

Absent

Cutaneous

respiration,

some have

bronchial (gill)

respiration

Gills/ book gills/

trachea/book

lungs

Circulatory

system

Absent

Absent

Closed type

Open type

Reproduction

Asexual

(fragmentation)

and Sexual,

hermaphrodite,

internal

fertilization,

development is

indirect (many

larval stages)

Dioecious, sexual

reproduction,

internal

fertilization,

development is

direct or indirect

Sexual,

earthworms

& leeches are

monoecious,

neries is

dioecious,

development

is both direct &

indirect.

Mostly

dioecious,

usually internal

fertilization,

mostly

oviparous,

development

is direct or

indirect