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BISHOP SCOTT BOYS’SCHOOL(Affiliated to CBSE, New Delhi) Affiliation No.: 330726, School Campus: Chainpur, Jaganpura,By-Pass, Patna 804453.Phone Number: 7061717782, 9798903550. ,Web: www.bishopscottboysschool.comEmail: [email protected]

STUDY COURSE MATERIALBIOLOGY

SESSION-2020-21CLASS -IX

TOPIC: DIVERSITY IN LIVING ORGANISMS

DAY-1

Topic- Detailed Classification of Kingdom Animalia

*NCERT Book Link-http://ncert.nic.in/textbook/textbook.htm?iesc1=7-15

*Teaching Notes-

R.H. Whittaker organized organisms into five kingdoms. He classified organisms

based on cell structure, mode, and source of nutrition and body design. The five

kingdoms proposed by Whittaker are Monera, Protista, Fungi, Plantae, and Animalia.

Let us learn about the animal kingdom, i.e., Kingdom Animalia.

Kingdom Animalia

Kingdom Animalia is composed of all animals. The animal kingdom is the largest

kingdom among the five kingdoms. Animals are multicellular eukaryotes. However,

they do not have a cell wall or chlorophyll like plants. Hence, members of the animal

kingdom have a heterotrophic mode of nutrition. Kingdom Animalia has been

classified into ten different subphyla based on their body design or differentiation.

The different phylum of the animal kingdom are as follows:

1. Porifera

2. Coelenterata (Cnidaria)

3. Ctenophora

4. Platyhelminthes

5. Nematoda

6. Annelida

7. Arthropoda

8. Mollusca

9. Echinodermata

10. Hemichordata

11. Chordata

1.Phylum Porifera

Porifera means organisms with holes. They are commonly known as Sponges.

Features of the poriferan are:

Non-motile, multicellular organisms with the hard outer skeleton.

Have a porous body.

Pores on the bodies create a canal system which helps in the circulation of

substances.

Not differentiated into head and tail; do not have a well-developed organ or organ

system.

Include Marine Habitat.

Asymmetrical or radially symmetrical.

Reproduction is both asexual by budding and gemmules and sexual through

fertilization.

Phylum Porifera is divided into the following three classes:

1. Calcarea.

2. Hexactinellida.

3. Demospongiae.

Example of phylum Porifera includes- Spongilla, Sycon.

2. Phylum Coelenterata (Cnidaria)

The term Coelenteratais derived from the Greek word “kilos” which means hollow-

bellied. Their features are:

Have a hollow body cavity.

The body is differentiated into two ends.

Includes all aquatic animals.

The body is made of two layers of cells: inner and outer linings.

Live in colonies (corals) as well as solitary (Sea anemone).

Respiratory, circulatory and excretory organs are absent.

Asexual reproduction by budding and sexual reproduction by gametes formation.

Phylun Coelenterates is divided into the following three classes:

1. Hydrozoa.

2. Scyphozoa

3. Anthozoa.

Example of phylum Coelenterata includes – Hydra, Jellyfish.

*PPT Link-https://www.slideshare.net/mobile/antoniettegeolina/kingdom-animalia-10086930

*Video Link-https://www.khanacademy.org/science/biology/crash-course-bio-ecology/crash-

course-biology-science/v/crash-course-biology-121

DAY-2

Topic- Ctenophora, Platyhelminthes and Nematoda.

*Teaching Notes-

3.Phylum Ctenophora

The term Ctenophora is derived from the Greek word “ktenos” which means comb and

“phora” which means carrying. Their features are:

Transparent body with biradial symmetry.

Two tentacles and eight longitudinal rows of ciliary comb-plates for locomotion

are present.

Marine, solitary and free-swimming.

No polymorphism or dimorphism occurs.

Examples of phylum Ctenophora includes – comb jelly, sea mitres etc.

4.Phylum Platyhelminthes

Platyhelminthes are commonly known as flatworms. Their features are:

Dorsoventrally flattened body.

Complex and have differentiated body structure.

Tissues are differentiated from three layers of cells and are triploblastic.

Do not have a true internal cavity or coelom.

Have bilateral symmetry.

Either free-living (Planaria) or parasitic (liver flukes).

Phylum Platyhelminthes is divided into o following three CLASS-

1. Turbellaria.

2. Trematoda.

3. Cestoda.

Example of phylum Platyhelminthes includes -Tapeworm, Planaria.

5.Phylum Nematoda

Phylum Nematoda consists of nematodes or roundworms. Their features are:

Nematodes have a cylindrical body.

Bilaterally symmetrical and triploblastic.

Have pseudocoelom, a false body cavity.

Sexes are separate.

Body is covered with a tough, resistant cuticle; cilia absent.

Parasitic and causes diseases such as elephantiasis, ascariasis.

Example of phylum Nematoda includes – Ascaris, Wuchereria.


*Video Link-https://youtu.be/fWVMKLsRE6s

DAY-3

Topic- Annelida and Arthropoda

*Teaching Notes-

6.Phylum Annelida

Annelids are commonly known as segmented or ringed worms. They have the

following features:

Have a segmented cylindrical body.

The body is differentiated into head and tail.


Have a true body cavity.

Exoskeleton absent; body is covered by a thin cuticle.

Alimentary canal is tube-like, complete and extends straight from mouth to anus.

Reproduction is by sexual means. Sexes may be united (hermaphrodite) or

separate.

Habitat: marine, freshwater, and land.

Phylum Annelida is divided into following three classes:

1. Polychaeta.

2. Oligochaeta.

3. Hirudinea.

Example of phylum Platyhelminthes includes -Tapeworm, Planaria.

7.Phylum Arthropoda

Arthropod means jointed legs. Animals which have jointed appendages belong to this

phylum. This is the largest phylum in the animal kingdom. Other features are:

They are bilaterally symmetrical.

Have jointed appendages, exoskeleton, and a segmented body.

Have well-differentiated organ and organ system.

Have an open circulatory system, but do not have differentiated blood vessels.

Alimentary canal is complete, mouth and anus lie at the opposite ends of the

body.

Respiration through general body surface, by gills, air tubes or book – lungs.

Sexes are usually separate; sexual dimorphism is well marked in several forms.

Terrestrial or aquatic, free – living, commensal or parasitic forms

Arthropoda forms the largest phylum of Animal kingdom.

Phylum Arthropoda is divided into following five classes:

1. Onychophora.

2. Crustacea.

3. Myriapoda.

4. Insecta.

5. Arachnids.

Example of phylum Arthropoda includes – Spiders, butterflies, and mosquitoes.




DAY-4

Topic- Mollusca and Echinodermata*Teaching Notes-

8.Phylum Mollusca

Phylum Mollusca consists of a large group of animals. Features are:


Less segmented body.

Well-developed organ and organ system.

Open circulatory system.

Limbs are present.

Digestive tract has a simple structure.

Excretion by a pair of metanephridia or kidneys.

Sexes are usually separate.

Sensory organs it touch, smell, taste and vision are present ( in some).

Aquatic, mostly marine, few fresh water and some are terrestrial forms.

The phylum Mollusca is divided into the following five main classes:

1. Polyplacophora.

2. Gastropods.

3. Scaphopoda.

4. Pelecypoda.

5. Cephalopods.

Example of phylum Mollusca includes- Snails and octopus.

9.Phylum Echinodermata

The term Echinodermata is derived from the Greek words, echinos meaning hedgehog

and derma meaning skin. Thus, echinoderms are spiny-skinned animals.

Radial symmetry and triploblastic.

Have true coelom.

Have hard calcium carbonate skeleton structure.

Digestive system is usually complete. Anus is absent in ophiuroids.

Excretory organs absent.

Reproduction sexual, asexual or by regeneration.

Sexes are separate.

Free-living marine animals.

Phylum Echinodermata includes the following five classes:

1. Crinoidea.

2. Holothuroidea.

3. Echinoidea.

4. Asteroids.

5. Ophiuroidea.

Example of phylum Echinodermata includes- Sea urchins, starfish.


*Video Link-

https://youtu.be/tRPJavxrxRo

DAY-5

Topic- Hemichordata and Chordata*Teaching Notes-

10.Phylum Hemichordata

The characteristics of phylum Hemichordata are as follows:

The body is soft, fragile, and divided into a proboscis.

The epidermis is single-layered.

It comprises worm-like marine animals with an organ-system level of

organization.

They have an open circulatory system.

They respire through gills since they are marine.

They have separate sexes and external fertilization.

Development is direct.

Examples- tongue worm etc.

11.Phylum Chordata

The Chordates possess the following characteristics:

They are bilaterally symmetrical, triploblastic with an organ-system level of

classification.

They possess a notochord and a nerve cord.

The circulatory system is closed type.

Chordata is the most advanced group of animals. It is divided into two groups-

A. Protochordata

B. Vertebrata.

Classification of Vertebrates

Vertebrates are classified into 7 classes based on their anatomical and physiological

features. They are:

Mammals (Class Mammalia)

This class of organisms have the ability to regulate their body temperature irrespective

of the surrounding ambient temperature. Therefore, mammals are called endothermic

animals and it includes humans and platypuses.

Birds (Class Aves)

From a biological perspective, birds are dinosaurs (more aptly called avian dinosaurs).

This class of organisms are characterised by feathers, toothless beaks and a high

metabolic rate. Furthermore, members of class Aves lay hard-shelled eggs.

Reptiles (Class Reptilia)

Reptiles include tetrapods such as snakes, crocodiles, tuataras and turtles. The

characteristic feature of reptiles is that they are ectothermic in nature. Snakes are still

considered tetrapods though they have no visible limbs. This is due to the fact that

snakes evolved from ancestors that had limbs.

Amphibians (Class Amphibia)

Amphibians include ectothermic tetrapods such as frogs toads and salamanders. The

distinguishing feature that separates amphibians from reptiles is their breeding

behaviour. Most amphibians need a body of water to breed as their eggs are shell-less.

Furthermore, they undergo metamorphosis where the young ones transform from fully

-aquatic larval form (with gills and fins) to terrestrial adult form.

Bony fishes (Class Osteichthyes)

This class of fishes is characterized by their skeleton which is composed primarily of

bone rather than cartilage (such as sharks). Class Osteichthyes is also the largest

class of vertebrates today.

Cartilaginous fishes (Class Chondrichthyes)

As the name suggests, this class is characterized by the cartilaginous skeleton.

Members include sharks, rays, skates and sawfish. Some sharks such as the massive

Greenland shark can live for several centuries. A specimen that was tagged in 2016

was found to be at least 273 years old.

Jawless fishes (Class Agnatha)

These are very primitive fishes that have not changed much from fossil records for

millions of years. They have a jawless, circular mouth with rows of small sharp which

aid in holding and feeding on other fishes. Most members of this class are parasites

and scavengers.

*Mind Map-




*Exercise Link-https://byjus.com/ncert-solutions-class-9-science/chapter-7-diversity-in-living-

organisms/

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