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diversityinlivingorganisms-

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The hierarchy of classification – Groups : Living organisms have been broadly classified into five
main kingdoms.
 They are :i) Monera ii) Protista iii) Fungi iv) Plante v) Animalia
 Each kingdom has been further classified into smaller
sub - groups at various levels as :Kingdom
Phylum (for plants) / Division (for animals)
Class
Order
Family
Genus
Species
 By arranging organisms on the basis of hierarchy and
characteristics
 into smaller and smaller groups we arrive at the basic
unit of
 classification called species.
The Five Kingdom classification of living organisms :Organisms
Prokaryotes
Eukaryotes
Monera
Unicellular
Multicellular
Protista
With cell wall
Do not perform
photosynthesis
Fungi
Able to perform
photosynthesis
Plantae
Without cell wall
Animalia
5 Kingdoms
 They are eukaryotic, unicellular, mostly aquatic
 Some have cilia or flagella which help them in moving
 The mode of nutrition may be autotrophic or
heterotrophic.
Example of Protista on next slide-
Protozoan
Diatoms
 They are mostly prokaryotic, unicellular, do not have a
definite nucleus
 May or may not have cell wall
 The mode of nutrition is autotrophic or heterotrophic.
Example of Monera on next slide-
Bacteria
Cyanobacteria
Mycoplasma
 These do not contain chlorophyll and hence are
heterotropic and have diverse modes of nutrition.
 They may be saprophytic i.e., depending on dead or
decaying organic matter for their food, or may be
parasitic i.e., depending on living organisms for their
food .
Example Fungi of is on next slide-
Agaricus
Plant Kingdom
INTRODUCTION
 Every organism whether plant or animal is unique in
itself. There is a wide diversity in the flora (plants) and
fauna (animals) in the world. The diversity we see
today is the result of 3.5 billion years of organic
evolution. During the course of this evolution several
species vanished from the surface of the Earth and
became extinct. It is estimated that more than fifty
times the existing species have become extinct.
With such a vast number of organisms - both living and
extinct, it becomes impossible to study every one of
them at individual level. This task of studying the
diversity of living organisms can be made easier and
more effective if the various organisms are arranged in
an orderly manner
Plant kingdom
PLANT KINGDOM
CRYPTOGAMAE
THALOPHYTA
BRYOPHYTA
PHANEROGAMAE
PTERIDOPHYTA
GYMNOSPERMAE
ANGIOSPERMAE
ALGAE
MONOCOT
FUNGI
DICOT
LICHENS
Eichler in 1883 suggested a system to classify the plant
kingdom which is well accepted. He said that the plant
kingdom is subdivided into two subkingdoms:
Cryptogamae and Phanerogamae. Sub kingdom
Cryptogamae are lower plants that do not bear flowers
or seeds.
(i)THALLOPHYTA
 The plant body is not differentiated into stem, root and
leaves but is in the form of an undivided thallus.
 Vascular tissues are absent.
 The reproductive organs are single-celled and there is
no embryo formation after fertilization.
 This division includes three sub-divisions: algae, fungi
and lichens.
Chara
(ii)BRIOPHYTA
 Bryophyte is a traditional name used to refer to
all embryophytes (land plants) that do not have
true vascular tissue and are therefore called 'non-vascular
plants'.
 Some bryophytes do have specialized tissues for the
transport of water; however since these do not
contain lignin, they are not considered to be true vascular
tissue.
 Currently bryophytes are thought not to be a natural
or monophyletic group; however the name is convenient
and remains in use as a collective term for mosses,
hornworts, and liverworts.
 Bryophytes produce enclosed reproductive structures
(gametangia and sporangia), but they produce
neither flowers nor seeds, reproducing via spores.
 The term bryophyte comes from Greek βρύον bryon, "tree-moss, oyster-green" + φυτόν fyton "plant".
Example of bryophyte is on next slide-
Marchantia
Moss
Marchantia (Liverwort)
(iii)Pteridophytes
 The Pteridophytes are vascular plants (plants
with xylem and phloem) that produce
neither flowers nor seeds, and are hence called
vascular cryptogams.
 Instead, they reproduce and disperse only via spores.
 Pteridophytes include horsetails, ferns, club mosses,
and quillworts.
 They are used for medicinal purposes, as soil -binders,
and are frequently planted as ornamentals.
Pteridophyte classification
They do not form a monophyletic group but is often taken
to consist of two groups:
The Lycopodiophyta (club mosses, spike mosses, and
quillworts),
"Monilophytes":
 Marattioid ferns,
 Equisetophyta (horsetails),
 Psilotophyta (whisk ferns) and Ophioglossophyta (adder's
tongues and grape ferns),
 Leptosporangiate ferns (the largest group of ferns).
Example Pteridophyte of is on next slide-
PHANEROGAMAE
 This division is made up of plants that bear flowers and
seeds and make up the majority of the larger plants. The
body is differentiated into true stem, leaves and roots.
 Propagation of the plant takes place with the help of
seeds.
 Seeds are formed as a result of sexual reproduction. The
male and female gametes fuse together inside the ovary
and develop into the seed.
 In some plants seed is not produced inside an ovary.
Phanerogamae is made into two further divisions.(i)Gymnosperms (naked seeded plants)
(ii) Angiosperms (Seed born within a fruit)
(i) GYMNOSPERMAE
 The gymnosperms are a group of seed-producing
plants that includes conifers, cycads, Ginkgo, and Gnetales.
 The term "gymnosperm" comes from the Greek word
gymnosperms (γυμνόςπερμοσ), meaning "naked seeds",
after the unenclosed condition of their seeds.
 Their naked condition stands in contrast to the seeds and
ovules of flowering plants (angiosperms), which are
enclosed within an ovary.
 Gymnosperm seeds develop either on the surface of
scales or leaves, often modified to form cones, or at the
end of short stalks as in (Ginkgo).
 Example of Gymnosperm on next slide-
Pines
Cycas
(ii) ANGIOSPERME
 This group constitutes the largest group of plants. Seeds
are produced inside an ovary which later becomes the
fruit. These are highly evolved group of plants. The plant
body is distinctly differentiated into roots, stem and
leaves.
 Based on the number of cotyledons (seed-leaves) that
form the seed this group is divided into:
 Monocotyledons (One seed leaf)
Example: Rice, Wheat
 Dicotyledons (two seed leaves)
Example: Beans, Mango
Example of Angiosperm, Monocot & Dicot plants on next
slide-
Angiosperm, Monocot & Dicot
plants
Bud of pink rose
Animalia Kingdom
 Animals are divided into ten groups & they are :-
Porifera
ii. Coelenterate
iii. Platyhelminthes
iv. Nematoda
v. Annelid
vi. Arthropoda
vii. Mollusca
viii. Echinodermata
ix. Protochordata
x. Vertebrata
i.
Animal kingdom
ANIMALIA
PORIFERA
COELENTER
ATA
PLATYHELM
I-NTHES
NEMATODA
ANNELIDA
ARTHROPOD
A
MOLLUSCA
PROTOCHOR
D-ATA
VERTEBRAT
A
PISCES
AMPHIBIA
REPTILA
AVES
MAMMALIA
(i)Porifera
 This word means organisms with holes.
 These are Non-motile animals attached to some solid
supports.
 There are pores ,all over the body. These lead to a canal
system that helps in circulating water throughout the
body to bring in food and oxygen(O2).
 The body design involves very minimal differentiation
and division into tissues.
 They are commonly called ‘Sponges’ and mainly found in
marine habitats.
Example of Porifera on next silide-
(ii)Coelentrata
 Two layered body which is radically symmetrical
 Aquatic in habitat which includes both fresh water and
marine
 The outer layer has tentacles armed with stinging cells
cnidoblasts which can release venom into the victim. The
inner layer encloses a body cavity called gastro vascular
cavity
 Animals in this group exist in two types of individuals
called zooids - polyps and medusae. Polyps are fixed and
lead solitary or colonial life, while medusae are free
swimming
 Alternation of generation takes place in colonial forms.
Polyps and medusae alternate with each other during the
life cycle
 Reproduction is usually asexual i.e., by budding in the polyp
form and sexual in medusa form
 Exoskeleton made of lime is found in corals
Example of Coelentrata on next silide-
Sea anemone
Jellyfish
(iii)PLATYHELMINTHES
 Simplest triploblastic organisms showing bilateral




symmetry
Mostly parasites in other animals
Body in dorsoventrally flat and leaf-like or ribbon-like
with bilateral symmetry
The body cavity has only one opening which serves as
both the mouth and the anus
Hermaphrodites i.e, male and female sex organs
present in one individual
Example of Platyhelminthes on next silide-
Tape worm
 They have cylindrical body.
 The body is bilaterally symmetrical and
triploblastic.
 They do not have true body cavity.
 They have tissues but no real organs.
 They are parasitic.
Example of Nematoda on next slide-
Ascaris
Wuchereria
(v)ANNELIDA
 Occur in moist soil, fresh water and sea
 Body is soft and segmented, triploblastic with bilateral
symmetry
 First animal with the coelom (body cavity)
 Body is covered by a non-chintinous cuticle which may
have chitinous setae, or parapodia
 Reproduction is generally sexual, but some may
reproduce asexually by rejuvination i.e, by regrowing
broken segments
Example Annelid on next silide-
Earthworm
(vi)Arthropoda
(Joint legged)
 They have bilaterally symmetrical body.
 The body is segmented.
 They have an open circulatory system
 The body cavity is filled with blood.
 They have jointed legs.
Example of Arthropoda on next slide-
Prawn
Spider
Scorpion
(vii)Mollusca
 They have bilateral symmetry.
 The coelomic cavity is reduced.
 There is little segmentation.
 They have open circulatory system and kidney like
organs
 for excretion.
 They have feet for moving around.
Example of Mollusca on next slide-
Octopus
Chiton
(viii)Echinodermata (Spiny skinned)
 They are spiny skinned organisms.
 They are free living marine animals.
 They are triploblastic and have coelomic cavity.
 The have water filled tube feet which help in
movement.
 They have hard skeleton made of calcium carbonate.
Example of Echinodermata on next slide-
Star fish
Sea cucumber
Sea urchin
(ix)Protochordata
 They have bilateral symmetry and are triploblastic.
 The have coelomic cavity.
 The have a notochord which is a long rod-like
structure
 along its back to which muscles are attached and help
in movement.
Example of Protochordata on next slide-
Herdemania
Amphioxus
(x)Vertebrata (Vertebrates)
 They have vertebral column and internal skeleton.
 They have bilateral symmetry and are triploblastic.
 They have coelomic cavity.
 Their body is differentiated into tissues and organs.
 Their body consists of four regions – head, neck, trunk
 and tail.
 They have two pairs of fins or limbs.
 The respiration in aquatic forms is by gills and in land
forms respiration is by lungs
 Vertebrates are grouped into five classes.
They are :-
vertebrates
Pisces
Amphibia
Reptilia
Aves
Mammilla
(i) Pisces (Fishes)
 They are fishes living in water. Their skin is covered
with scales or plates & they respire using gills.
 They have streamlined body and fins which help them
to move in water.
 They are cold blooded and their heart has only two
chambers.
 They lay eggs from which the young ones hatch out.
 Some fishes have skeleton made of cartilage like
Sharks, Rays etc. and some have skeleton made of
bones and cartilage like Tuna, Rohu etc.
Example of Pisces on next slide-
Shark
Tuna
Rohu
(ii)Amphibia (Amphibians)
 They are found in land and water.
 They do not have scales but have mucous glands on
their skin.
 They are cold blooded and the heart is three
chambered.
 Respiration is through gills or lungs.
 They lay eggs in water.
Example of Amphibia on next slide-
Frog
Salamander
Toad
(iii) Reptilia (Reptiles)
 They have scales and breathe through lungs.
 They are cold blooded.
 Most of them have three chambered heart but
crocodiles have four chambered heart.
 They lay eggs with hard covering in water.
Example of Reptilia on next slide-
Snake
Lizard
Crocodile
(iv) Aves (Birds)
 They are warm blooded animals.
 They have four chambered heart.
 They breathe through lungs.
 They have an outer covering of feathers.
 Their two fore limbs are modified into wings for flying.
 They lay eggs.
Example of Aves on next slide-
Crow
Stork
Ostrich
(v) Mammalia (Mammals)
 They are warm blooded animals.
 They have four chambered heart.
 They have mammary glands for production of milk to
nourish their young ones.
 The skin has hairs and sweat glands.
 Most of them give birth to their young ones.
 Some of them lay eggs (like Platypus and Echidna).
Example of Mammalia on next slide-
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