Class 9 Diversity in living orgainsms
Chapter
7
Diversity
on living Organisms
-
Greek thinker Aristotle classified animals on the basis of their living whether on land, air or water.
2.Charles
Darwin first described this idea of evolution in 1859 in his book,
The Origin of Species.
3.Robert
Whittaker (1959) proposed five kingdoms: Monera, Protista, Fungi,
Plantae and Animalia.
Sub-
groups at various levels.
Kingdom
Keep
Phylum Place
Class Clean
Order Or
Family
Family
Genus
Get
Species Sick
-
MONERA
They
are Unicellular prokaryotic. (Prokaryotic
do not having a defined nucleus.)
Some
of them have cell walls and some of them do not.
Mode
of nutrition is either autotrophic or heterotrophic.
Examples:
- Bacteria, blue green algae
2.
PROTISTA
They
are Unicellular eukaryotic. (Eukaryotic
having a defined nucleus.)
Some
of them have hair like structure called flagella for moving.
Mode
of nutrition is either autotrophic or heterotrophic.
EUGLENA
is the exception in this case. IT is also known as Plant
Animal.
Examples:
- Algae, Protozoans
3.0
FUNGI
They
are heterotrophic eukaryotic. (Heterotrophic
means dependent for food on
others.)
Have
capacity to become multicellular organisms at certain stages in their
life.
Have
cell walls made of tough complex sugar called chitin.
Also
known as SAPROPHYTES
because
they use decaying organic material as food.
Examples:
- Yeast, Mushrooms
4.0
PLANTAE
They
are multicellular eukaryotic autotrophs.
(AUTOTROPHS
means who makes food themselves and are not dependent for food on
others.)
Use
chlorophyll for photosynthesis.
Cell
wall is present.
They
show definite growth.
All
plants are included in this group.
5.0
ANIMALIA
They
are multicellular eukaryotic heterotrophs.
No
cell walls are present.
They
grow upto certain age or period.
All
animals are included in this group.
PLANTAE
A)
THALLOPHYTA
Plants
that do not have well differentiated body design fall in this group,
commonly algae.
These
plants are mainly aquatic.
Vascular
tissue is absent.
Examples:
- Spirogyra, Algae
B)
BRYOPHYTA
Called
amphibians of the plants kingdom.
More
advance than thallophytes.
Body
is commonly differentiated to form stem and leaf – like structure.
Vascular
tissue is absent.
Examples:
- Moss , Riccia
C)
PTERIDOPHYTA
The
body is differentiated into roots, stem and leaves.
Vascular
tissue is present.
EXAMPLES
:- Fern , Marsilea
Plants
with well differentiated
reproductive tissues that
ultimately make
seeds
are called Phanerogams.
PHANEROGAMS
is classified into two groups:-
GYMNOSPERMS
AND ANGIOSPERMS
GYMNOSPERMS
Gymno
means
naked and
spermed
means
seed.
Bear
naked seeds.
These
are usually perennial, evergreen, and woody
EXAMPLES:
- Pines and
Deodar
ANGIOSPERMS
Angio
means
covered and
spermed
means
seed.
The
seeds develop inside an organ which is modified to become a fruit.
THUS, these are also called flowering plants.
ANGIOSPERMS
are classified into two divisions on the basis of their cotyledons –
Plants
having single cotyledon are known as MONOCOTS
and
plants having two or more than two cotyledons are known as
DICOTS.
(Cotyledons
means embryonic leaf in seed-bearing plants.)
|
MONOCOTS
|
DICOTS
|
|
Single
cotyledon in seed
|
Two
cotyledons in seed
|
|
Parallel
venation in leaves
|
Reticulate
venation in leaves
|
|
Have
petals in multiple of 3
|
Have
petals in multiple of 4 or 5
|
|
Have
fibrous roots
|
Have
tap roots
|
ANIMALIA
1.
PORIFERA (with pores)
Non
– motile animals attached to some solid support.
have
pores over all the body which leads to canal system that helps in
circulating water to bring food and water that’s why they are
commonly
known as SPONGES .
Covered
with a hard outside layer called Skeleton.
EXAMPLES
:- Spongilla , Silcon
2.
COELENTRATA
They
have body made up of two layers of cells.
Body
has 2 - 3 segments.
More
body design differentiation.
EXAMPLE:
Hydra, Jellyfish
3.
PLATYHELMINTHES
Body
is dorsoventrally flattened so called flatworms.
There
is no true body cavity or coelom.
They
are hermaphrodite.
EXAMPLE
:- Liverflukes
4.
Nematodes
Body
is cylindrical so called roundworms.
Pseudo
coelom is present.
They
are unisexual.
EXAMPLES
:- Roundworm , Filara worm
5.Annelids
Body
is segmented from head to tail.
They
don't have jointed legs
True
body cavity is present.
They
have closed circulatory system.
EXAMPLE:
Earthworm, leech
6.ARTHROPODS
Body
has 2 -3 segments.
They
have jointed legs.
Body
cavity is blood filled
They
have open circulatory system.
EXAMPLES
:- Cockroach , Buttefly
7.MOLLUSCA
Body
shows little segmentation.
Coelomic
cavity is reduced.
They
have foot for locomotion
They
are soft bodied with shells on the body.
EXAMPLE:
Snails, mussels
8.
ECHINODERMATA
Body
is not segmented.
Coelomic
cavity is present.
They
have water drives tune system.
Skin
is of calcium carbonate.
Examples:
Starfish, feather stars.
VERTEBRATA
True
vertebral column and internal skeleton.
Billaterally
symmetrical.
Paired
gill pouches.
Dorsal
nerve chord.
Coelomate
Notochord
Triploblastic
PROTOCHORDATA
These
animals are billaterally symmetrical, triploblastic, have a coelom.
|
Notochord
|
Nervechord
|
|
Back
bone
|
Spinal
chord
|
|
Bones
|
Brain
|
|
|
|
Pisces
Body
is covered with scales
Breathe
through gills.
Heart
is two chambered.
Eg:
shark, rohu
AMPHIBIA
Lack
of scales
Mucus
glands in the skin
3
chambered heart
Respiration
either through gills or lungs
They
lay eggs
Both
found in water and land
EXAMPLES:
- Frogs and Salamanders
REPTILIA
Cold
blooded
Have
scales
breathe
through lungs
3
chambered heart except crocodile that have 4 chambered heart
Lay
eggs with tough coverings
EXAMPLES:
- Snakes, lizards, turtles
AVES
Warm
blooded
4
chambered heart
Lay
eggs
Outside
covering of feathers
2
forelimbs for modifies for flight
Breathe
through lungs
EXAMPLES
:- ALL BIRDS
MAMMALIA
Warm
blooded animals
4
chambered heart
Mammary
glands are present for the production of milk to nourish their young
ones
Skin
has hairs as well as oil and sweat glands
Produce
live young ones
Kangaroos
give birth to very poorly develop young ones.
EXAMPLES
:- HUMAN , CAT
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