This document provides information on the Kingdom Animalia and its various phyla. It begins with an introduction to key characteristics of animals and criteria for classification. It then describes the following phyla in more detail: Porifera, Cnidaria, Platyhelminthes, Aschelminthes, Annelida, Arthropoda, Mollusca, Echinodermata, Hemichordata, Chordata, and its subphyla Vertebrata, Cephalochordata, Urochordata. Within the subphylum Vertebrata, it discusses the characteristics of classes: Pisces, Chondrichthyes, Osteichthyes, Amphibia, Re
2. Introduction
1.2 billion animal species, with great diversity.
Diversified in habitat, level of organisation, body plan,
symmetry, body cavity, germ layers, mode of
locomotion, physiological processes (respiration,
reproduction, circulation, excretion).
Number of germ layers
Animal body pattern
Body symmetry
Body cavity
Body segmentation (metamerism)
Body support
Criteria for classification
3. Phylum Porifera
Pore bearing (ostia & osculum)
Solitary, colonial & sedentary
Marine & fresh water, assymetrical
Cell aggregate pattern, no tissue formation
Spongocoel
Flagellated choanocytes/collar cells + amoeboid cells (digestion)
Spicules – CaCO3/Silica/Spongin fibres
Feeds on Detritus ()
Digestive system absent
Reproduction – Asexual (Budding/Gemmule), sexual
(Gametes)
Power of regeneration
Kingdom -- Animalia
Phylum -- Porifera
Example -- Sycon
4. Phylum Coelenterata/Cnidaria
Solitary/colonial & sedentary
Marine & fresh water, radial symmetry
Blind sac pattern , Tissue level organisation
Coelenteron/gastrovascular cavity, Acoelomates.
Cnidocytes in tentacles (nematocysts) – offence & defence
Reproduction – Asexual
(Budding/Gemmule), sexual (Gametes)
Power of regeneration Kingdom -- Animalia
Phylum -- Cnidaria
Example -- Hydra
• Two forms Polyp (sedentary, cylindrical) & medusa (free
swimming, umbrella shaped)
5. Kingdom -- Animalia
Phylum -- Platyhelminthes
Example – Liverfluke
Phylum Platyhelminthes
Flat worms, Body – leaf like/ribbon shaped, ,unsegmented
Free living/endoparasitic, bilaterally symmetrical
Dorsoventrally flattenned,cuticularized, hooks &suckers present.
Blind sac pattern, acoelomate
Digestive system absent.
Excretory system – Flame cells/Protonephridia
Nervous system – nerve ring & nerve cords.
Reproductive system is well developed (hermaphrodite).
Locomotory organs, sense organs are absent.
High power of Regeneration
6. Phylum Aschelminthes
Round worms,
Endoparasitic, cylindrical, bilaterally symmetrical
Tube within tube pattern, pseudocoelomate.
Dorsoventrally flattenned,cuticularized, hooks &suckers present.
Digestive system complete.
Excretory system – Canals/Protonephridia
Nervous system – nerve ring & nerves
Sexual dimorphism – male short narrow – post end shows penial
setae (copulation)
Female – longer & broader straight posterior end.
7. Kingdom -- Animalia
Phylum -- Annelida
Example -- Earthworm
Phylum Annelida
Ring worms,
Free living /Endoparasitic, cylindrical, bilaterally symmetrical
Tube within tube pattern, true coelomate.
Elongated, cylindrical, metameric segmentation.
Digestive system complete
Locomotion – setae, parapodia/suckers
Respiration – body surface, Respiratory pigment – heamoglobin
Excretion – nephridia,
Circulatory system closed type
Nervous system – nerve ring & ganglionated
Hermaphrodite, few unisexual.
Ectoparasites (leech) – sanguivorous (blood sucking)
Anticoagulant – hirudin.
8. Kingdom -- Animalia
Phylum -- Arthropoda
Example -- Prawn
Phylum Arthropoda
Solitary, colonial (Barnacles are sedentary), Omnipresent.
Free living /Endoparasitic -- sanguivorous, cylindrical, bilaterally
symmetrical.
Chitinous exoskeleton (ecdysis/moulting)
Body divisible into head, thorax
& abdomen. (in some cephalothorax)
Tube within tube pattern, true coelomate.
Metameric segmentation
Feeds on detritus, flesh
Digestive system is complete, mouth
parts – sucking/biting/chewing.
Legs for crawling, creeping, walking,
wings for flying
9. Circulatory system -- open type (blood flows
through open sinuses & bathes the organs)
Respiratoy organs – gills/trachea/book lungs/book
gills
Excretion -- green glands/malphighian tubules.
Nervous system – nerve ring, double ventral
ganglionated nerve cord
Sense organs – antennae, compound eyes, taste
receptors
Sexual dimorphism, oviparous (except
scorpion), fertilization internal, honey bees
(parthenogenesis)
Few are economically important
(honey bees, silk worm, lobster, prawn)
Few are harmful eg. mosquito/centipede
/crab/spider/cockroach act as vectors.
10. Soft bodied animals
Free living/sedentary, marine (benthoic, pelagic), marshy places.
Tube within tube pattern,
Bilateral symmetry, assymetrical (torsion i.e. twisting)
Body divisible – head, foot & visceral mass – enclosed by mantle
(muscular fold).
Phylum Mollusca
Mantle secretes shell – external/internal or absent.
Feed on plants & animals
Locomotion – arms/foot (creeping, burrowing & swimming)
Digestive system well developed, due to torsion intestine bends
takes “U” shaped curve.
Mouth & Anus lie close, buccal cavity shows radula provided
with transverse rows of teeth.
11. Respiration -- Aquatic forms -- gills called ctenidia. Terrestrial –
lungs
Circulatory system -- open (except sepia), blood contains
haemocyanin (blue coloured with Cu).
Excretion – Kidney (organ of bojanus).
Nervous system – 3 pairs of ganglia (head, pedal & visceral)
,connected by commissures & connectives.
Sense organs – eyes, tentacles, osphradia (purity of water).
Sexes are separate, oviparous, development is direct/indirect.
Kingdom -- Animalia
Phylum -- Mollusca
Example -- Snail
12. Kingdom -- Animalia
Phylum -- Echinodermata
Example -- Starfish
Spiny skinned animals
Solitary, Free living/sedentary, exclusively marine (gregarious,
benthoic),.
Tube within tube pattern,
Radial symmetry pentamerous
Body – spherical/elongated, without well defined head.
Exoskeleton – spiny, calcareous plates or ossicles.
Characteristic feature -- Water vascular system (madreporite)
used for locomotion.
Feeding – carnivorous,
Phylum Echinodermata
13. locomotion – arms & tubefeet
Respiration – peristomial gills, papillae.
Circulatory system – reduced, open type , heart absent.
Nervous system – ring around mouth & radial nerves in
arms.
Sexes are separate(sometimes bisexual)
Fertilisation – External, development is indirect
High power of regeneration.
Kingdom -- Animalia
Phylum -- Echinodermata
Example -- Starfish
14. Acorn worms
Free living, few sedentary, Exclusively marine(bottom of sea in
burrows)
Body is soft, fragile, vermiform, unsegmented & divided into probocis,
collar & trunk.
Buccal cavity – diverticulum – rod shaped
Feed on microbes by ciliary action.
Alimentary canal is complete, straight/’U’ shaped.
Respiration – paired gills arranged in longitudinal rows in trunk.
Gills open by gill slits.
Circulatory system – simple & closed, blood is colourless.
Nervous tissue is embedded in dorsal & ventral sides.
Sexes are separate (few bisexual) fertilisation – external, development
– indirect (free swimming larva).
Connecting link – non-chordates & chordates
Phylum Hemichordata
15. Phylum -- Chordata
Subphylum --Invertebrate
Chordate
Subphylum -
-
Vertebrata
Cephalochordat
a
Urochordata
Division Gnathostomata
Class
-
Super Class -
Pisces
Tetrapoda
Class -
Chondrichthyes
Osteichthye
s
Class
Mammalia
Aves
Reptili
Agnatha
Cyclostomat
a
Amphibia
16. Cartilagenous notochord (at least in the embryonic stage)
Gill slits – neck region
Hollow dorsal nerve cord.
Invertebrate Chordates - link between invertebrates & chordates
Invertebrate chordate -- Urochordata, Cephalochordata.
Chordata includes Urochordata, Cephalochordata &
Vertebrata.
Salient Features of Chordata
17. Eg Botryllus, Herdmania, Dololium
Exclusively marine, pharynx – gill slits
Also called as TUNICATES
Body is soft covered by test (tunicine).
Notochord – only in larval tail, lost during metamorphosis
Salient Features of Urochordata
18. Eg Amphioxus
Fish like animals rarely exceed 5 cms
Also called as LANCEOLATES
Partly buried in soft marine sediments
Notochord – throughout the length & life.
Show chordate characters – pharyngeal gill slits, tail & dorsal
nerve cord.
Salient Features of Cephalochordata
19. Phylum -- Chordata
Subphylum --Invertebrate
Chordate
Subphylum -
-
Vertebrata
Cephalochordat
a
Urochordata
Division Gnathostomata
Class
-
Super Class -
Pisces
Tetrapoda
Class -
Chondrichthyes
Osteichthye
s
Class
Mammalia
Aves
Reptili
Agnatha
Cyclostomat
a
Amphibia
21. Super Class
Pisces
Aquatic, poikilothermic.
Locomotion – muscles & fins, Caudal fins -- steering
Exoskeleton – dermal scales, endoskeleton –
cartilagenous/bony
Body – streamlined & boat shaped
Mouth – terminal/ventral, Respiration -- gills
Circulation – single & closed, blood is red (RBC’s)
Heart – 2 chambered, ventral
Brain – well developed, large olfactory lobes
Sexes are separate, mostly oviparous, few
viviparous
22. Class
Chondrichthyes
Cartilagenous endoskeleton – placoid scales
Exclusively marine
2dorsal fins, claspers are present
Mouth – ventral
Tail fin unequal heterocercal
5 to 7 pairs of gill slits,not covered by operculum
Fertilisation – internal, viviparous.
23. Class
Osteichthyes
Bony endoskeleton – cycloid/ctenoid scales
Aquatic – fresh & marine
Single dorsal fin, claspers absent
Mouth – terminal
Tail fin has equal lobes -- homocercal
4pairs of gill slits covered by operculum
Fertilisation – external, oviparous.
24. Class Amphibia
Lives on land & water(fresh)
Carnivorous, poikilothermic, differentiated into head,
trunk & tail, neck is absent. (in some adults tail is absent.)
Webs are digited (swim), Skin - moist, glandular
(mucous)
Two pairs of limbs from girdles (pelvic & pectoral)
Intestine & digestive glands – well developed
Prominent ear drums/tympanic membranes -- lateral
Circulatory system – closed, heart – 3 chambered &
ventral, RBC’s are biconvex, nucleated
Respiration – skin/lungs & bucco-pharynx
Nervous system – well developed
Sexual dimorphism, oviparous, fertilisation is
external, &metamorphosis
25. Class Reptilia
First true terrestrial vertebrates
Aquatic, semiaquatic, marshy areas, carnivorous
Locomotion – pentadactyle digits & clawslimbs
Skin is dry, non glandular covered by
scales/scutes/plates
Snakes – limbless, crawl on belly, poikilothermic
Ear drums depressed
Circulatory system – closed, heart – ventral, 2
complete auricles & ventricles incompletely
partitioned
Respiration – lungs, olfactory lobes & cerebellum
better developed.
Sexes are separate, fertilisation – internal,
oviparous,lay shelled eggs & show parental care
26. Class Aves
Aerial mode of life, forelimbs are modified into wings
Hind limbs – walking & running
Body is differentiated into head, neck, trunk & tail.
Exoskeleton – feathers, scales are on hind limbs.
Body is streamlined, homeotherms
Skin is dry, non glandular, bones are hollow
pneumatic
Jaws are modified into beak, teeth absent, crop &
gizzard are present.
Blood is red, RBC’s – biconvex & nucleated, heart is
ventral, perfectly four chambered, double
circulation.
Respiration – lungs, air sacs – increase buoyancy
Brain – well developed cerebellum --- equilibrium
27. Class Aves
Sexes are separate, sexual dimorphism --
prominent
Oviparous, shelled eggs with yolk & albumin
Fertilisation -- internal
Urinary bladder -- absent
Parental care, seasonal migration is common
Only left ovary & oviduct, reduces body weight.
28. Class Mammalia
Mammary glands – characteristic feature
Terrestrial, aquatic, arboreal, aerial, mostly
herbivorous, few are carnivores, some are
omnivores
Body differentiated into head, neck, trunk & tail
Locomotion -- Limbs
Exoskeleton – hair, fur, nails, hooves
Skin – glandular, sweat & sebaceous (oil)
Body cavity – diaphragm thorax & abdomen
Presence of external ear/Pinnae
Heterodont teeth, double circulation, RBC’s
biconcave & anucleated, blood is red, ventral heart,
four chambered
29. Class Mammalia
Respiration – Lungs, brain well developed,
cerebrum -- corpus callosum.
Optic lobes better developed than olfactory lobes
Few are oviparous, some have pouches for
development of young ones (marsupials).
Majority are placental & viviparous.