Chapter -1 Classification Notes
Points to remember about Animal Kingdom

It is divided into many phylum as given below in the chart.

Each phylum is further subdivided into many classes given below.
Details about Phylum Arthropods:
Chapter -1 Classification Notes
Arthropods is divided into four classes
Athropods
Key features of Insects:

3 pairs of jointed legs

2 pairs of wings

1 pair of antennae

3 body segments: Head,
Thorax, Abdomen

1 pair of compound
eyes

Breath through tracheae
Key features of Crustaceans:

5-7 pairs of legs

2 pairs of antennae

2 body segments:
Cephalothorax(fused
head and thorax),
Abdomen

Exoskeleton often
calcified to form a
particularly hard
carapace, for
Chapter -1 Classification Notes

protection .
Compound eyes

Breath via Gills, live in water!
Key features of
Arachnids:
 4 pairs of legs no
wings

2 body parts:
Cephalothorax,
Abdomen

all have piercing
jaws since all are
predator

chelicerae (pointed
mouthparts) for
biting and
poisoning prey
Key features of Millipedes:

long, thin body with many
segments for moving easily
through soil and leaf litter

each segment has jointed legs
(>9 pairs)

1 pair of antennae as sense
organs in dark habitats
Chapter -1 Classification Notes
Other phylum of invertebrates:
Nematods:



long worms, thin body with no segments.
They live in diverse habitats.
Some of them are parasitic.
Other phylum of invertebrates:
Annelids:
 Annelids are worms, with bodies made up of ring-like segments.
 Most of them live in water, some like the earthworm live in moist soil.
 Compound eyes.
Other phylum of invertebrates:
Mollusca:
 Molluscs are soft-bodies animals, sometimes with a shell (snails) or
without (slugs).




slimy bodied
Radula is the rasping organ.
Mantle cavity is present.
Eyes on tentacles.