Download arothropoda

In Greek arthros means joint podos means foot.
The phylum arthropoda is the largest phylum in the
animal kingdom. These animals have joint legs.
They are called the joint-legged animals or the
arthropods. The species so far identified in
arthropoda represent about 80% of the total animals
species.
There are more than 875000 species of animals
under this phylum.
They are triploblastic animals. Members of this
phylum are found almost every where.The speciality
of these animals is to adjust to all type of
environments. They are found in marine, limnetic,
terrestrial and aerial habitats of this world. They are
also found in deserts and caves. Some are burrowing
form also.There are also parasitic forms under this
group.
The body may be elongated or
segmented. Each segment of the Body, bears
a pair of appendages. These appendages are
modified into Jaws, feet or gills.
There is a well developed exoskeleton made
up of chitinous Plates on the body. The
exoskeleton is protective and supporting in
function.
The body is divided into three regions
namely head, thorax and abdomen.
Muscles found in these animals are
complex in their nature and are capable of
contraction
The body presence of
chitinous
exoskeleton does
not permit free
growth of the
animal. This
exoskeleton is shed
at intervals and
there is a formation
of new layer. This
process is called
MOULTING or
ECDYSIS
• HAEMOCOEL: Coelom is reduced and
the body cavity is filled with blood and is
called HAEMOCOEL.This is a colourless
fluid.
• DIGESTIVE SYSTEM: Digestive system is
complete and the appendages near the
mouth parts are modified for cutting,
piercing and sucking the food items.
Pharynx, oesophagus, crop, gizzard,
intestine are helpful in digestion.
RESPIRATORY SYSTEM
Respiration in these
animals occurs through
the body surface, gills,
trachea, or by book lungs.
VASCULAR SYSTEM
IN ARTHROPODA THE VASCULAR
SYSTEM IS OPEN TYPE WITH A
DORSAL HEART , ARTERIES
AND HAEMOCOEL.
NERVOUS SYSTEM
• IN ARTHROPODA
THE NERVE
SYSTEM IS
ALMOST LIKE
THAT OF
ANNELIDESAND
CONSISTS OF A
NERVE RING,
GANGLION AND A
NERVE CORDS.
SENSE ORGANS
• Sense organs consist of well
developed eyes gustatory
organs and antenna,
balancing organs and auditory
organs.
Excretory organs: Excretory
organs are Malphigian tubules or
green glands help in the process
of excretion.
Reproduction: Reproduction is of
sexual type. Sexes are separate.
ECONOMIC IMPORTANCE OF
ARTHROPODS
 Insects help in pollination.
 Beetles, ants, larvae improve the soil condition by
their burrowing activity.
 Ants and Termites destroy plant waste products and
enrich the soil which provides nutrients to the plants.
 Dung beetle decays animal waste.
 Some insects help in biological control.
 Silk moth provides silk which is of great value.
 Honey Bees provide honey which is a natural
antiseptic and also nutritive food, and veewax.
 Lac insects provides lac used in paints and toys.
 Arthropods like crab, prawn and lobster are used as
food
HARMFUL ARTHROPODS
Some insects like termites destroy
wood materials like furniture, cloth,
books etc.
Locusts destroys crops.
Mosquitoes and flies spread diseases.
Cockroaches destroy food materials and
spread diseases.
PICTURES OF ARTHROPODS
BEETLE
LADY BIRD
CRAYFISH
COCKROACH
LOBSTER