DIVERSITY IN LIVING DIVERSITY IN LIVING ORGANISMSORGANISMS

WRIT

TEN AND E

DITED B

Y :-

NANDEESH LAXETTY

IX C

INTRODUCTIONEvery 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

THALLOPHYTATHALLOPHYTA

The plant body is not differentiated into The plant body is not differentiated into stem, root and leaves but is in the form of an stem, root and leaves but is in the form of an undivided thallus.undivided thallus. Vascular tissues are absent. Vascular tissues are absent. The reproductive organs are single-celled The reproductive organs are single-celled and there is no embryo formation after and there is no embryo formation after fertilization. fertilization. This division includes three sub-divisions: This division includes three sub-divisions: algae, fungi and lichens. algae, fungi and lichens.

BRIOPHYTA

• Moss and Liverwort belong to this variety of plants. There are the simplest form of land plants. The plant body is flat and lack true leaves and roots. The upper surface of the plant body produces a stalk which bears a capsule. The capsule contains spores.

PTERIDOPHYTAPTERIDOPHYTA The plant body is differentiated into The plant body is differentiated into stem, leaves and roots. stem, leaves and roots. Vascular system is present. Vascular system is present. Leaves usually have leaflets. Spores Leaves usually have leaflets. Spores are borne on the undersurface of the are borne on the undersurface of the leaf. leaf. They grow in damp cool shady They grow in damp cool shady places. places.

Examp le

ALGAEALGAE► Occur in ponds, lakes and fresh water Occur in ponds, lakes and fresh water

bodies. Sea weeds are found in marine bodies. Sea weeds are found in marine waters. waters.

► May be single celled, colonial or May be single celled, colonial or filamentous. filamentous.

► Are autotrophic i.e., they can prepare their Are autotrophic i.e., they can prepare their own food with the help of the green pigment own food with the help of the green pigment i.e., chlorophyll present in the plant. i.e., chlorophyll present in the plant. Sometimes red, blue, yellow and brown Sometimes red, blue, yellow and brown pigments are found. pigments are found.

► Blue-green bacteria (cyan bacteria) are Blue-green bacteria (cyan bacteria) are included in this group of plants. included in this group of plants.

Examp les

FUNGIFUNGI

These do not contain chlorophyll These do not contain chlorophyll and hence are heterotrophic and and hence are heterotrophic and have diverse modes of nutrition. have diverse modes of nutrition. They may be saprophytic i.e., They may be saprophytic i.e., depending on dead or decaying depending on dead or decaying organic matter for their food, or organic matter for their food, or may be parasitic i.e., depending on may be parasitic i.e., depending on living organisms for their food living organisms for their food

Examp leExamp le

LICHENSLICHENS► This is a group which has two varieties of This is a group which has two varieties of

plants, an algae and a fungus living in plants, an algae and a fungus living in perfect harmony. They co-exist for perfect harmony. They co-exist for mutual benefit. This relationship is known mutual benefit. This relationship is known as symbiosis. The fungus absorbs water as symbiosis. The fungus absorbs water and mineral salts and supplies it to the and mineral salts and supplies it to the alga. The alga prepares food and supplies alga. The alga prepares food and supplies it to the fungus. it to the fungus.

Examp les

KINGDOM PHANEROGAMAEKINGDOM PHANEROGAMAEThis division is made up of plants that bear flowers This division is made up of plants that bear flowers and seeds and make up the majority of the larger and seeds and make up the majority of the larger plants. The body is differentiated into true stem, leaves plants. The body is differentiated into true stem, leaves and roots. Propagation of the plant takes place with the and roots. Propagation of the plant takes place with the help of seeds. Seeds are formed as a result of sexual help of seeds. Seeds are formed as a result of sexual reproduction. The male and female gametes (sex cells) reproduction. The male and female gametes (sex cells) fuse together inside the ovary (female part of the fuse together inside the ovary (female part of the flower) and develop into the seed. In some plants seed is flower) and develop into the seed. In some plants seed is not produced inside an ovary. Phanerogamae is made not produced inside an ovary. Phanerogamae is made into two further divisions. into two further divisions. Gymnosperms (naked seeded plants) Gymnosperms (naked seeded plants) Angiosperms (Seed borne within a fruit) Angiosperms (Seed borne within a fruit)

DIVISION GYMNOSPERMAE• Gymnosperms are

intermediate between cryptogams and angiosperms. The male flower is a cone which produces pollen. The female flower is much larger and consists of a rosette of carpals which bear ovules along the two margins.

DIVISION 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)

Anima l K ingdom:- The following classification “telescope” clearly indicates the mechanism behind the classification of the

Animal Kingdom

The cha r t g i ven be low br ie f ly out l i nes the c l a s s i f i ca t i on o f the An ima l K ingdom. 

ANIMALIA

PORIFERA

COELENTERATA

PLATYHELMINTHES

NEMATODA

ANNELIDA

ARTHROPODA

MOLLUSCA

PROTOCHORDATA

VERTEBRATA

PISCES AMPHIBIA REPTILA AVES MAMMALIA

PORIFERAPORIFERA The simplest multicellular The simplest multicellular animals. The cells are loosely animals. The cells are loosely held together and do not form held together and do not form tissues tissues Aquatic in habitat (mostly Aquatic in habitat (mostly marine) marine) Ostia (pores) are present all over Ostia (pores) are present all over the body, with a single large the body, with a single large opening on top called osculum opening on top called osculum Food and oxygen enter the Food and oxygen enter the organism along with water into organism along with water into a canal system a canal system Support system made up of Support system made up of tiny needle-like formations. tiny needle-like formations. They may be made of silica, They may be made of silica, calcium or sponging fibers calcium or sponging fibers Reproduction may be sexual, Reproduction may be sexual, asexual or budding asexual or budding Example: Sycon, Spongilla, Example: Sycon, Spongilla, Euptectella Euptectella 

COLLENTERACOLLENTERATATA

Two layered body which is radically Two layered body which is radically symmetrical symmetrical Aquatic in habitat which includes both fresh Aquatic in habitat which includes both fresh water and marine water and marine The outer layer has tentacles armed with The outer layer has tentacles armed with stinging cells cnidoblasts which can release stinging cells cnidoblasts which can release venom into the victim. The inner layer venom into the victim. The inner layer encloses a body cavity called gastro vascular encloses a body cavity called gastro vascular cavity cavity Animals in this group exist in two types of Animals in this group exist in two types of individuals called zooids - polyps and individuals called zooids - polyps and medusae. Polyps are fixed and lead solitary medusae. Polyps are fixed and lead solitary or colonial life, while medusae are free or colonial life, while medusae are free swimming swimming Alternation of generation takes place in Alternation of generation takes place in colonial forms. Polyps and medusae colonial forms. Polyps and medusae alternate with each other during the life cycle alternate with each other during the life cycle Reproduction is usually asexual i.e., by Reproduction is usually asexual i.e., by budding in the polyp form and sexual in budding in the polyp form and sexual in medusa form medusa form Exoskeleton made of lime is found in corals Exoskeleton made of lime is found in corals Example: Hydra, Obelia, Aurelia, Meridian Example: Hydra, Obelia, Aurelia, Meridian 

PLATYHELMINTHESPLATYHELMINTHESSimplest triploblastic Simplest triploblastic organisms showing bilateral organisms showing bilateral symmetry symmetry Mostly parasites in other Mostly parasites in other animals animals Body in dorsoventrally flat Body in dorsoventrally flat and leaf-like or ribbon-like and leaf-like or ribbon-like with bilateral symmetry with bilateral symmetry The body cavity has only one The body cavity has only one opening which serves as both opening which serves as both the mouth and the anus the mouth and the anus Hermaphrodites i.e, male and Hermaphrodites i.e, male and female sex organs present in female sex organs present in one individual one individual Example: Planaria, Liver Example: Planaria, Liver Fluke, Tape Worm Fluke, Tape Worm

ANNELIDAANNELIDA Occur in moist soil, fresh Occur in moist soil, fresh water and sea water and sea Body is soft and segmented, Body is soft and segmented, triploblastic with bilateral triploblastic with bilateral symmetry symmetry First animal with the coelom First animal with the coelom (body cavity) (body cavity) Body is covered by a non-Body is covered by a non-chintinous cuticle which may chintinous cuticle which may have chitinous setae, or have chitinous setae, or parapodia parapodia Reproduction is generally Reproduction is generally sexual, but some may sexual, but some may reproduce asexually by reproduce asexually by rejuvination i.e, by regrowing rejuvination i.e, by regrowing broken segments broken segments Example: Nereis (sand worm), Example: Nereis (sand worm), Aphrodite (sea mouse), Aphrodite (sea mouse), Pheretima (earthworm), Pheretima (earthworm), Hirudinaria (leech) Hirudinaria (leech)

ARTHROPODAARTHROPODA ► This is the largest phylum with This is the largest phylum with almost 80% of the animal almost 80% of the animal kingdom kingdom 

► Body is bilaterally Body is bilaterally symmetrical and segmented. It symmetrical and segmented. It is divided into head, thorax and is divided into head, thorax and abdomen abdomen 

► Possess jointed legs which may Possess jointed legs which may be modified for walking, be modified for walking, swimming feeding and feeling swimming feeding and feeling 

► Exoskeleton is chitinous which Exoskeleton is chitinous which is shed periodically by is shed periodically by moulting moulting

► Body cavity is reduced and Body cavity is reduced and filled with blood (haemocoel) filled with blood (haemocoel) 

► Respiration is by lungs, book Respiration is by lungs, book lung and trachea lung and trachea

► Example: Apis (honey bee), Example: Apis (honey bee), Araneae (Spider), Palaemon Araneae (Spider), Palaemon (prawn), Scolopendra (prawn), Scolopendra (Centipede) (Centipede) 

MOLLUSCA Aquatic in habitat but some land forms are also seen

Body is soft and divided into three regions (head, dorsal visceral mass and ventral foot)

Body enclosed in a hard calcareous she

Breathe through gills, land molluscs have lungs

Sexes are separate Example: Chiton, Pila

(snail), unio (fresh water mussel), octopus 

ECHINODERMAECHINODERMATATA

Marine in habitat Marine in habitat Body is radially Body is radially symmetrical, star shaped, symmetrical, star shaped, spherical or elongate, spherical or elongate, Exoskeleton is spiny Exoskeleton is spiny Head is absent and five Head is absent and five radially arranged arms radially arranged arms present present Locomotion is with the Locomotion is with the help of tube feet help of tube feet Sexes are separate Sexes are separate Example: Asterias (star Example: Asterias (star fish), Echinus (sea fish), Echinus (sea urchin), Holothuria (sea urchin), Holothuria (sea cucumber), Antedon cucumber), Antedon (feather star) (feather star)

REPTILEREPTILE Mostly terrestrial Mostly terrestrial Heart is 3 chambered, is Heart is 3 chambered, is cold blooded cold blooded Breathe through lungs Breathe through lungs Body covered with scales Body covered with scales Have two pairs of Have two pairs of pentadactyl (five digit) pentadactyl (five digit) limbs which are absent in limbs which are absent in snakes snakes Example:  Hemidactylus Example:  Hemidactylus (wall lizard), chameleon, (wall lizard), chameleon, Draco (flying lizard)Draco (flying lizard)

AMPHIBIAAMPHIBIALive in both water Live in both water and on land and on land Respiration is by Respiration is by gills, lungs or skin gills, lungs or skin 3 chambered heart 3 chambered heart Is cold blooded Is cold blooded Have two pairs of Have two pairs of pentadactyl (5 pentadactyl (5 digit) limbs which digit) limbs which may be absent in may be absent in some cases some cases

AVESAVES Arboreal in habitat i.e, Arboreal in habitat i.e, they live on trees they live on trees Warm blooded. 4 Warm blooded. 4 chambered heart chambered heart Body covered with Body covered with feathers feathers Lungs have membranous Lungs have membranous extensions called air sacs extensions called air sacs to make the body light to make the body light Mouth is surrounded by a Mouth is surrounded by a beak. Teeth are absent beak. Teeth are absent Fore-limbs are modified Fore-limbs are modified into wings into wings

MAMMALIAMAMMALIAMost intelligent of all Most intelligent of all organisms organisms Warm blooded with 4 Warm blooded with 4 chambered heart chambered heart Give birth to young ones Give birth to young ones The mother suckles her The mother suckles her young ones on milk young ones on milk secreted by special glands secreted by special glands called mammary glands called mammary glands Body covered with hair Body covered with hair Have two pairs of Have two pairs of pentadactyl limbs pentadactyl limbs Breathe through lungs Breathe through lungs 

I AM MAMMAL!!