Chapter # 10

Kingdom Animalia
By: Faiz Rasool
Lecturer Biology
 Includes animals, name animalia is derived from Latin,
Anima= Breath or soul.
 In traditional two kingdom systems, the multi-cellular
animals were referred to broadly as Metazoa to
distinguish from one celled animals, the Protozoa.
 In five kingdom system traditional protozoa belong to
kingdom Protoctista. Kingdom animalia includes all
animals which are multi-cellular, diploid, eukaryotic,
ingestive heterotrophs and develop from two dissimilar
haploid gametes, a large egg and smaller sperm.
 It is believed that animals have evolved from protoctists
but when and in which environment???? Still questions.
 Aschelminthes (Nematoda)
Deuterostomes Proterostomes Platyhelminthes

Coelomates Pseudocoelomates Acoelomates

Cnidaria

Bilateria Radiata Porifera

Eumatazoa Parazoa

Protoctist ancestors
 Echinodermata

Chordata Hemichordata

Mollusca
Annelida Arthropoda

Deuterostomes Proterostomes
 Grade Radiata Grade Bilateria

➢Radial symmetry ➢Bilateral symmetry

➢The body can be cut in two ➢The body can be cut in two
equal halves from any plane of equal halves only from single
division passing from central plane of division passing from
axis. central axis.
➢Diplobastic ➢Triplobastic
➢Phylum Cnidaria ➢Phylum Platyhelminthes to
Chordates.
 Diplobastic Triplobastic
➢Division radiata (Cnidaria) ➢Grade Bilateria
➢Body consists of 2 layers, ➢Body consists of 3 layers,
ectoderm and endoderm ectoderm, mesoderm and
➢Jelly like mesenchyma is endoderm
present between 2 layers ➢Greater degree of specialization
➢No specialized organs and ➢Special transport systems
systems ➢Integumentary and nervous
➢No transport system system develop form ectoderm
➢Sac like digestive sytem ➢Endoderm give rise to digestive
➢Only one cavity, Gastro vascular system and associated glands
cavity. ➢Mesoderm give rise to muscular,
skeletal, reproductive etc
➢Tube like digestive system
 Acoelomates Pseudocoelomates Coelomates
➢No body cavity or ➢Space between body ➢Coelom is present
coelom wall and digestive ➢True body cavity
➢Mesoderm forms tube is pseudocoelom present between body
loose Jelly like ➢Not lined by wall and alimentary
mesenchyma is coelomic epithelium canal
between 2 layers. ➢Not developed from ➢Develops by
➢Gut is sac like mesoderm splitting of mesoderm
➢No transport system ➢Bounded externally ➢Outer parietal layer
➢No excretory system by muscles and underlines body wall
➢Simple nervous internally by chitin ➢Inner visceral layer
system is present. ➢No relation with any covers alimentary
system canal
➢Phylum ➢Phylum ➢Phylum Annelida
Platyhelminthes Aschelminthes to Chordata
 Proterostomia Deuterostomia
❑Cleavage of zygote is spiral or ❑Cleavage is radial and
determinate indeterminate
❑Mouth develops from blastopore ❑Mouth forms from some
or from anterior margin distance to blastopore
❑Coelom is formed by splitting of ❑Blastopore develops into anus
mesoderm ❑Coelom is derived from
❑Mesoderm is derived from outpouching of archenterons
anterior lip of blastopore ❑Mesoderm derives from wall of
developing gut
❑Phylum Mollusca, Arthropoda & ❑Phylum Echinodermata to
Annelida Chordata
 Commonly called as sponges
 Habitat aquatic, only 150 species are present in fresh
water out of 5000. Others are marine.
General characteristics
 Multicellular but not have tissue level organization and
no organ formation.
 Asymmetrical

 Body wall is composed of pinacoderm and choanoderm

made up of pinacocytes and choanocytes respectively.
 Gelatinous mesenchyma may contain amoeboid cells
and spicules or sponging fibers between them.
 Size ranges from few millimeter wide to more then 1
meter, macroscopic.
 Spongocoel may be divided into flagellated chambers
or canals.
 Body wall have ostia for water entrance and osculum
for water leaving.
 Respiratory and circulatory organs are absent.
 Sponges are sessile.
 Their food include zooplankton, phytoplankton (20%)
and detrital organic matter (80%). Water currents move
food towards them.
 Food enters the spongocoel through ostia where
choanocyte ingest it.
 Waste materiel may diffuse out by body wall or flow
out through osculum.
 Sponges are stationary however larva are able to swim
 No definite nervous system, neurosensory and neuron
cells are present to coordinate the flow of water.
 Skelton contains spicules which may be calcareous or
siliceous. The bath sponge have spongin fiber. The
skeleton is present among pinacocyte and provides
support. Osculum and ostia also have spicules.
 Sponges reproduce sexually and asexually.
 Asexual reproduction is by budding, buds may be
external or internal, internal buds are called as
gemmules.
 Sponges reproduce Sexually, they are hermephrodite,
mostly protoandrous (male sex cells develop first).
Some sponges are dioceous, sperms are released in
water and fertilization occurs in mesenchyma, blastula
and larval stages are present.
 Sycon

 Leucoselenia
 Euplectella

 Spongilla
Importance
 Washing and bathing

 Industry (absorb water)

 Surgical operations (fluid and blood)

 Sound absorption in buildings

 Best commercial are present in Mediterranean sea

 Assigned name due to Cnidocytes which give rise to
nematocysts.
 Diploblastic (organ formation).
 In Ectoderm nematocysts are present and endoderm
cells are specialized for digestion.
 Mesoglia is also present b/w these layers.
 Gastrovascular cavity or enteron.
 Sac like digestive system.
 Radial symmetry
 Habitat Aquatic, fresh and marine water
 Size ranges from microscopic Hydra to macroscopic
Branchioceranthus (a hydrozoan polyp 2 m in length).
 Dimorphism exist in two different forms polyps
(gastrozoids) and madusae (sexual reproduction).
 Feeding mouth is surrounded by tentacles having
nematocysts (stinging cells) for defense and offence.
 Carnivorous (feed small organisms) immobilize the
prey by nematocysts and take into gastro-vascular
cavity (digestion and absorption)
 Nervous system in the form of nerve net or plexus in
body wall, no central N.S.
 Exoskeleton formed of calcium carbonate
 Sessile cnidarians are Hydra, obelia, sea anemone and
corals.
 Free living and motile cnidarians are jelly fish.
 Solitary individuals are jelly fish, hydra and sea
anemone.
 Colonial are physalia, vellela.
 Reproduction asexual by budding in hydra. In obelia
polyps reproduce asexually and produce medusae.
Medusae reproduce sexually and forms colonies (called
alternation of generations).
 Polymorphism (a character of coelenterates) the
occurrence of structurally and functionally more than
two different types of individuals (called zooids) e.g.
obelia.
 Hydra (fresh water)

 Obelia (marine water)

 Aurelia (jelly fish)

 Actinia (sea anemone)

 Medrepora (corals)
 Coral reefs
Polyps of corals are covered by stony cups (from
mouth of stony cup polyps can pass out and in). Stony
network is called as corals, a no. of stony networks join
and form coal reefs, mostly of calcium carbonate (lime
stone).
 Occurrence in coastal waters of

❖ Florida

❖ West Indies
❖ East coast of Africa, Australia

❖ Islands of Coral sea

General Characters
 Name means the “flatworms”.

 Soft bodied, dorsoventrally compressed.

 Triploblastic, acoelomates, body is un-segmented.

 Parasites, mostly endo-parasite (common in tropics).

Size
 Few mm (10 mm in Planaria) to several meters
(Tapeworm).
Digestive system branching, sac type. Poorly developed
in parasites.
 Excretory system branching tubes ending in bulb like
cells called flame cells.
 Nervous system well developed in the form of nerves
network and ganglion. Sense organs are present at
anterior end.
 Respiratory and circulatory systems are absent.
 Nutrition parasites absorb from host and free living
from dead organic matter.
 Locomotion free living move by cilia. In parasites
movement is restricted.
 Reproduction both by sexual (hermaphrodite) and
asexual (binary fission) means. Larval form is present
sometimes in sexual reproduction.
 Dugesia (Planaria) free living

 Fasciola (Liver fluke)

endoparasite of sheep and
man (bile duct).
 Taenia (Tape worm) endoparasite of man, cattle and
pig. Complete life cycle in 2 hosts.
 Resistant cuticle instead of epidermis.
 Adhesive organs for attachment such as suckers and
hooks.
 Degeneration of muscular and nervous systems.
 Simple digestive system.
 Complicated reproductive system, huge number of ova
are produced.
 Complex life cycle and complete life in more than two
hosts.
 In Taenia zygote starts to develop as it is in uterus of
female. The last segments (proglottids) contain fully
developed embryo.
 Mature proglottids break from body and pass out along
feces from human body.
 Embryo inside egg is round with six chitinous hooks.
 Remain embedded in voluntary muscles of 2nd host
(cow).
 If improperly cooked beef is eaten, parasite start to
develop in intestine of man.
 Once parasite has entered in intestine of man, it is
difficult to remove completely.
 Should cook beef properly to avoid from entrance.
 Certain medicines are available to remove it.
 Besides drugs “anema” is also used.
 Complete removal is necessary because if only head
remains in body, it can develop into new tape worm
again.
 General characters name nematoda means the pointed
ends. Animals are elongated and with pointed ends.
 Triploblastic, pseudo-coelomates.
 One end is anterior, but no clear head and sense organs.
 Bilateral symmetry and body is un-segmented.
 Number of protein rich fluid filled vacuolated cells are
present which maintain hydrostatic pressure.
 Size ranges from microscopic to one meter in length.
 Digestive system is in the form of alimentary canal
with 2 openings (mouth and anus). Absent in parasites.
 Fluid filled space is present between alimentary canal
and body wall making tube within tube structure.
 Excretory system consists of longitudinally running
canals that join at anterior end to make single canal that
opens to the exterior through excretory pore on ventral
surface of body.
 Nervous system in the form of nerve ring around
pharynx from which dorsal, ventral and lateral nerve
cords arise and run along whole body of worm.
 Sense organs in the form of sensory papillae on lips.
 Circulatory and respiratory systems are absent.
 Gases exchange through body surface.
 Locomotion is by four bands of muscles from which
two pairs are dorso-lateral and two ventro-lateral.
Circular muscles are absent.
 Reproduction is sexual and sexes are separate, female
gonads produce eggs and male gonads produce sperms,
larval stage is present in life cycle.
 Importance (parasitic diseases)
 Very serious diseases in man and plants.
 Ascaris lumbricoides
is intestinal parasite of man.
 Rhabditis genus is present in soil,
organic matter, water and feces of
man and animals.
 Enterobius vermicularis commonly
called as pin worm is cosmopolitan
but more common in Europe and
America.
 Pin worms are parasites of
human caecum, colon and anus,
cause itching of anus and
inflammation of mucous
membrane of colon and appendix.
Result in insomnia and loss of appetite.
 Ancylostoma duodenale called hook worm is parasite
of human intestine in Asia, North Africa and Europe.
 It is very dangerous because holds the villi of intestine
and suck blood and body fluid.
 During feeding release some anticoagulant to prevent
clotting of blood and after feeding leave the wound
bleeding. In children it causes severe anemia and retard
physical and mental growth.
 Round worms are every where
and decay organic matter.
A single rotting apple may
contain 90,000 worms.
Billions thrive in each acre of top soil.
 General Characters most worms which we are
familiar, are segmented (Latin word meaning little
ring).
 Body is metamerically segmented, divided transversely
into number of similar parts.
 The subdivisions may be indicated externally by
constrictions, internally by septa.
 Various systems of body (gut, blood vessels, nerve
cord) are continues penetrating each segment.
 Triploblastic, coelomates with bilateral symmetry.
 Digestive system in form of alimentary canal divided
into distinct parts performing specific functions. Mouth
at anterior end and anus at posterior end. Mouth is
overhung by a bi-lobed structure called Prostomium.
 In parasitic life poorly developed digestive system.
 True coelom made by splitting of mesoderm, Parietal
layer (covers body wall) and Visceral layer (covers
alimentary canal). Filled by coelomic fluid.
 Excretion takes place by nephridia (ciliated organs
present in each segment).
 Central nervous system well developed comprising of
simple brain and solid, double, longitudinal ventral
nerve cord (nerves arise in each segment from it).
 Circulatory system first invertebrates which have
closed blood circulatory system (blood confined to
blood vessels). Also transports gases and nutrients.
 Respiratory system is absent, gases exchange through
body surface (by skin and blood vessels) by diffusion.
Skin is kept moist by mucus and coelomic fluid.
 Locomotion takes place by two types of muscles in
body wall.
a) Circular muscles along circumference of body.
b) Longitudinal muscles along length of body.
 Locomotion takes place by interaction of muscles and
hydrostatic skeleton. Contraction of circular muscles
produces pressure in coelomic fluid and causes
elongation of body. Similarly longitudinal muscles
widen the body.
 Chitinous chaetae or setae are embedded in each
segment (sacs) or on parapodia, which help in
locomotion. Absent in leech.
 Reproduction is sexual. Earth worm and leech are
hermaphrodite while in neries the sexes are separate
and external fertilization takes place with freely
swimming trochophore larva.
 Burrowing activity of earth worm permits greater
penetration of air into soil and improves drainage
capacity of soil. Also improves root growth. Mixing
and churning of soil takes place. On this activity it is
termed as Natural plough.
 Classification divided into 3 classes.
i. Class Polychaeta have distinct head with eyes and
structures called as palps and tentacles. Organ of
locomotion are parapodia. Sexes separate. Mainly
aquatic (marine). Trochophore larva is present.
 Examples Nereis, Chaetopterus
ii. Class Oligochaeta have internal and external
segmentation. Organs of locomotion are setae. Head
not prominent. Terrestrial or aquatic. Hermaphrodite
with no larva.
 Examples Lumbricus terrestris, Pheretima posthuma
and other earth worms.
iii. Class Hirudinea body has fixed number of
segments, each segments has additional ring called as
annuli.
 Do not have organs of locomotion, move through
contraction of body and suckers. Hermaphrodite with
larva. Aquatic. No distinct head but leeches have
chitinous jaw to puncture host skin. Secrete
anticoagulant into wound to allow smooth flow of
blood into digestive system, where it can be stored for a
long time.
 Examples Hirudo medicinalis
(Parasite) Medicinal Leech.
 General characters contains more species than any
other phylum. Name means Arthron = Joint and Pods =
feet. Cockroaches, Grasshoppers, Butterflies and
Mosquitoes are most common examples.
 Body is segmented, each segment attached with other
by means of thin and flexible cuticle. Possess jointed
appendages for various functions.
 Origin is believed from annelids due to some common
characters i.e. segmented body, appendages and cuticle.
 Habitat exploit every type of habitat i.e. on land, water
(both fresh and marine) and air.
 Structure has a lot of variety, some are worm like
centipedes while others are flying insects with three
distinct regions of body, the head, thorax and
abdomen. Body is covered by water proof chitinous
cuticle secreted by epidermis.
 Coelom is not present in main body cavity, instead
haemocoel has developed which communicates with
blood vascular system.
 Digestive system is in the form of alimentary canal
with two openings mouth and anus. Divided into
different parts each for a specific function. Food
comprises of small plants and animals.
 Excretory system is present in form of Malpighian
tubules, nitrogenous wastes are excreted in form of
Uric acid.
 Nervous system is highly developed consisting of pair
of ganglion (simple brain) connected with double
ventral nerve cord from which a ganglion arise in each
segment of body. Nerves arise from these ganglion and
communicate with body. The sensory organs are paired
eyes and antennae.
 Respiration is mostly done by extensive tracheal
system formed of air tubes called as trachea for the
exchange of gases. Main tubes open outside trough
paired spiracles. Aquatic respire though gills and book
lungs.
 Blood circulatory system is unique. It is open
circulatory system and blood baths each cell. However
there is primitive heart and a main blood vessel. Blood
is colorless without Hemoglobin.
 Exoskeleton is present as outer covering of cuticle
which is light in weight and made of Chitin. It provides
surface for the attachment of muscles and help in
locomotion.
 Locomotion is active and swift. They swim, crawl or
fly depending upon habitat. Organ of locomotion are
paired appendages and in some cases paired wings.
 Reproduction is sexual with separate sexes. The testes
and ovaries produce sperms and eggs.
 Metamorphosis (meta=change, morphe=form). This
abrupt change of form and structure during life cycle.
There are three morphologically distinct stages in life
cycle, the egg develop into larva, larva converts into
motionless pupa that finally develops into adult.
 In some primitive insects the metamorphosis is
incomplete and the larva resembles adult (called as
nymph or instar). Lives in same habitat as adult.
 Classification it is a large group with great variety,
divided into several classes;
1. Class Crustacea: These are aquatic and have gills
for respiration.
 On the dorsal side of cephalothorax the exoskeleton
is in form of carapace.
 Deposition of salts in exoskeleton makes it more
firm.
 Appendages are modified for capturing food,
walking, swimming, respiration and reproduction.
 Coelom is reduced in the form of hoemocoel.
 Head has two pairs of antennal appendages, one pair of
mandibles (jaws) and two pairs of maxillae.
 Sexes are separate.
 Examples are Daphnia, -Cyclops, Crabs, lobsters,
Prawns and Wood louse.
2. Class Insecta:
 This is the largest group of not only arthropoda but of
all the animal kingdom and has great variety.
 Found every where and many show social behavior.
 Body has three distinct regions head, thorax and
abdomen.
 There are a pair of antennae and compound eyes on
head.
 The head is vertical to body and jaws are ventrally
placed.
 The thorax has three segments each of which has a pair
of jointed legs and one or two pairs of wings.
 Abdomen has varying number of segments.
 Brain is formed of fused ganglia double nerve cord is
ventral.
 Sexes are separate and animals are oviparous.
 Metamorphosis takes place during life.
 Examples are dragonfly, mosquito, butterflies, moths,
wasps and beetles.
3. Class Arachnida:
 Body has the anterior segments that are fused to form
cephalothorax with a pair of appendages called
chelicerae with claws, two pairs of padipalps and four
pairs of legs.
 There are no antennae and no true jaws.
 Abdomen may or may not be segmented with or
without appendages.
 Respiration is by gills or by special structures called
book lungs.
 Excretion is by malpighian tubules.
 Eyes simple, sexes separate and no true
metamorphosis.
 They are oviparous.
 Examples Scorpions, Spiders, Mites and Ticks.

4. Class Myriapoda:
 The body is divided into a
number of segments each
having a pair of legs.
 A pair of antennae and eyes are present on head.
 Examples are Centipedes and Millipedes.
 Have higher forms of characters such as Bilateral
symmetry, triploblastic, coelomic fluid and organ
system have reached the peak of invertebrate evolution.
 Two of main achievements are the chitinous
exoskeleton and lcomotary mechanism.
 The animals can walk, swim and fly.
 Exoskeleton Chitin is non living, non cellular and
secreted by under lying epidermis. It is made of
polysaccharides. On outside of chitin there is waxy
layer. In certain parts the chitin is soft and flexible.
 Skeleton is mainly for protection and also provides site
for the attachments of muscles and help in locomotion.
 Chitin in jaws is used for biting and crushing the food.

 It also forms the lens of compound eyes, copulatory

organ and organs of defense and offence.
 Moulting/ecdysis it is shedding of chitinous
exoskeleton time to time in young Arthropods for the
growth. In short exoskeleton is one of the primary
factors in success of Arthropods.
Economic Importance
Man and insects have been at war for same food and
habitat. They attack man, his domestic animals and
crops, causing a number of diseases. Some are
beneficial too.
 Harmful insects: Many types of mosquitoes, flies, lice
and bugs transmit disease causing organism to man and
domestic animal.
 Anopheles genus of mosquito transmits Plasmodium
and cause Malaria.
 Trypanosoma is transmitted by Tsetse fly of African
countries and causes African sleeping sickness. Some
species also cause diseases in cattle.
 Common house fly carries disease causing organisms
to contaminate food and cause Cholera and Hepatitis
etc.
 A no. of insects lay eggs on fruits, sugar cane, maize,
cotton and vegetables. The larvae of theses insects
cause damage to these commodities.
 The Locusts that move in large number from country to
country and cause damage to crops and other plants.
 Beneficial insects: Honey bee provides man with
honey and wax.
 Silk worm provides silk
 Some are predaceous to harmful insects.
 Some are scavengers and eat dead animals and plants.
 Insect larvae are source of food for fish.
 General characters Consists of diverse group of
organisms which include slow moving snails, slug, bi-
valved clams and highly active cephalopods.
 Contains over 50,000 living species and is the second
largest phylum of invertebrates.
 Giant squid is largest invertebrate animal.
 Have diversity of form but are built on same basic plan.
 Triploblastic, Coelomates, Bilateral symmetry and have
shell.
 Protection Body is covered with epithelial envelop
called Mantle which secrets calcareous shell.
 It is protective but handicap to locomotion, so some
active animals do not have it.
 Habitat molluscs are widely distributed. Some are
aquatic (Cephalopods), fresh or marine water. The
others include terrestrial living on moist places (land
snail).
 Body form un-segmented and soft, can be divided into
head, a ventral muscular foot and a dorsal visceral mass
containing most of internal organs. Over this mass
mantle is present which secretes shell. The space
between shell and mantle cavity contains gills in some
species. Some species have rasping tongue Radula
with horny teeth in their mouth.
 Body is organized with highly developed digestive,
respiratory. Circulatory, nervous and reproductive
systems.
 Digestive system is in form of tube with two openings.
 Excretory system is in form of paired nephridia.
 Circulatory system is open except in cephalopods.
Coelom is divided into sinuses or blood spaces. Heart
pumps blood into sinuses. A respiratory pigment of
blue color called Haemocyanin is present.
 Gases exchange is mostly by gills, in some cases
(snail) the mantle is converted into a lung.
 Nervous system is present in form of 3 pairs of
interconnected ganglia present in head, foot and body
regions.
 Locomotion is by muscular foot. However in some
species the movement is very slow. Others are sessile.
 Sexes are separate and larva is present.
 Classification divided into six classes, major are;
i. Gastropoda: Asymmetrical body covered with one
piece coiled shell. The animal withdraw itself into
shell. Both aquatic and terrestrial species are
included. Aquatic have gills while land forms mantle
cavity into lung.
 Examples: Helix aspersa: Snail.
 Limax: Slug
ii. Bivalvia (Pelecypoda): Bilaterlly symmetrical
aquatic molluscs.
 Body is laterally compressed and enclosed by 2
pieces of shell, so called bivalvia.
 Respire with plate like gills.
 Examples
 Mytilus: Marine mussel
 Anodonta: Freshwater mussel
 Ostrea: Oyster
iii. Cephalopoda: Bilaterlly symmetrical with dorso-
ventrally flattened body.
 All species are aquatic.
 Shell is much reduced and internal, absent in some.
 Highly developed and active.
 Examples:
 Loligo: Squid
 Sepia: Cuttlefish
 Octopus
 Some molluscs are indirectly harmful to man but most
of them are beneficial.
 Harmful molluscs
 Slugs are injurious to gardens and cultivations. They
not only eat leaves but also destroy plants by cutting
stem and roots.
 Teredo, a shipworm damages wooden parts of ships.
 Beneficial molluscs
 Large quantities of clams, oysters and mussels are
eaten in Fareast, Europe and America.
 Oysters are regarded as delicacy.
 Shells of freshwater mussels are used in button
industry.
 Shells of oysters are mixed with tar to make roads in
America.
 Shells in certain parts of world are used as ornaments.
 Some oysters also make value-able pearls e.g. the pearl
oyster.
 The brain of octopus is exceptionally large and
complex for an invertebrate brain. It is enclosed in shell
like case of Cartilage and endows the octopus with
highly developed capabilities to learn and remember. In
laboratory, octopus can rapidly learn to associate
certain symbols and open a screw jar to get the food.