Chapter 19: CLASSIFCATION OF LIVING ORGANISMS

Chapter 19: Classification of Living Organisms Class 10 Science and Technology (212) NIOS Textbook Solutions

Chapter 19. CLASSIFCATION OF LIVING ORGANISMS

INTEXT QUESTIONS 19.1

1. What does biodiversity mean?

Answer: Biodiversity means the variety of living beings found on Earth.

2. Define (i) species, (ii) biosphere (iii) ecosystem.

Answer:  (i) Species : Group of interbreeding populations

(ii) Biosphere : Livable part of earth

(iii) Ecosystem: an area whose inmates interact with each other and also the physical sorroundings.

3. Name the three levels of biodiversity.

Answer: The three levels of biodiversity are ecological diversity, species diversity and genetic diversity.

4. What is meant by biodiversity hotspots?

Answer: Hot spots are those areas of a country where some typical plants and animals (organisms) are exclusively present.

INTEXT QUESTIONS 19.2

1. What is meant by classification?

Answer: Classification means the process of grouping living organisms into different categories based on their similarities and differences.

2. How has classification made study of diversity possible?

Answer: Classification has made the study of diversity possible by grouping the enormous variety of living organisms into categories, making their study easier and systematic.

3. Name the three domains into which all the organisms of the world are categorised

Answer: The three domains into which all organisms of the world are categorised are  archaea , bacteria  and eukarya

4. Name the five kingdoms of life and mention the three features on which this classification is based.

Answer: The five kingdoms of life are  Monera, Protoctista (Protista), Fungi, Plantae and Animalia .

5. Study the table 19.2 on kingdoms of life and fill in the names of kingdom at A to E in the flow chart given below :

Photo

Answer: A= Monera, B= Protoctista, C= Fungi, D=Plantae, E= Animalia

INTEXT QUESTIONS 19.3

1. Find out the scientific name of the following :

Frog, cat, China rose, onion.

You may get them from someone in your neighbourhood who knows Biology or from internet or some Biology book.

Answer: The scientific names are:

Frog — Rana trigina .

Cat — Felis domestica

China rose — Hibiscus rosa sinensis

Onion — Allium cepa

2 In the following table, fill in plus (+) for present and minus (-) for absent to show the difference between plants and animals.

Features	Plant	Animal
Chlorophyll Muscles Nerves Locomotion Leaves and Roots Mouth and Anus

Answer:

Features	Plant	Animal
Chlorophyll	+	-
Muscles	-	+
Nerves	-	+
Locomotion	-	+
Leaves and Roots	+	-
Mouth and Anus	-	+

3. See the pictures of the two arthropods shown below. Mark one similarity and one difference

Photo

Answer: Similarity = jointed legs / Head divided into head, thorox and abdomen.

Differences = Number of pairs of legs .

4. Which out of ABCD is

a. Fungus b. Fern c. Moss d. Alga

Photo

Answer: A= Algae, B= Moss, C=Fungus, D=Fern .

5. Photo

Write the name of the phylum to which each of the animal shown in the pictures above, belongs.

Answer: a . Earthworm → Annelida

b. Pila → Mollusca

c. Round worm → Aschehelminthes

d. Hydra → Cnidaria

e. Sponge → Porifera

f. Starfish → Echinodermata

g. Fish → Chordata

h. Humans → Chordata

TERMINAL EXERCISES

1. Define biodiversity. Mention its three levels and briefly explain them.

Answer: Biodiversity is the term given to the variety of organisms that live on Earth.

Biodiversity has three levels:

(i) Genetic diversity: variation in genes among individuals of the same species.

(ii) Species diversity: variety of different species present in a particular area.

(iii) Ecosystem diversity: variety of ecosystems such as forests, grasslands, deserts and aquatic ecosystems present on Earth.

2. What are the global and Indian patterns of biodiversity? What do you mean by a 'hot spot' of diversity?

Answer: Biodiversity is not distributed equally across the world. Generally, it is richer in tropical regions and decreases towards the poles. Countries near the equator have greater biodiversity because of favourable climate conditions. India is one of the world’s megadiverse countries and has rich biodiversity due to variations in climate, landforms and ecosystems.

A hot spot of diversity is a region with very high biodiversity and a large number of endemic species (species found only in that region) that is under threat from human activities and habitat loss. In India, the Western Ghats and the Eastern Himalayas are important biodiversity hot spots.

3. Name the three domains of life and state one distinguishing features of each.

Answer: The three domains of life are:

(i) Archaebacteria are thermophilic or heat loving bacteria that live in high temperature vents.

(ii) Eubacteria are single celled organisms without well developed nucleus.

(iii) Eukarya are all other organisms with a well formed nucleus in their cell/cells.

4. Name the five kingdoms of life and state one feature of each of the kingdoms which differs from that of the others.

Answer: The five kingdoms of life are:

(i) Monera: Organisms are unicellular and prokaryotic (without a true nucleus).

(ii) Protista: Organisms are mostly unicellular and eukaryotic (with a true nucleus).

(iii) Fungi: Organisms do not have chlorophyll and obtain food by absorption.

(iv) Plantae: Organisms contain chlorophyll and make their own food by photosynthesis.

(v) Animalia: Organisms cannot make their own food and show movement (locomotion).

5. Give an account of the classification of Kingdom Plantae into its divisions. Cite examples.

Answer: Kingdom Plantae is classified into the following divisions:

(i) Thallophyta – Plant body is not differentiated into root, stem and leaves. These are simple plants.
Example: Algae (Spirogyra).

(ii) Bryophyta – Small plants with no true roots, stems and leaves. They usually grow in moist places.
Example: Moss (Funaria).

(iii) Pteridophyta – Plants have true roots, stems and leaves and reproduce through spores.
Example: Fern (Pteris).

(iv) Gymnosperms – Seed-producing plants with naked seeds (not enclosed in fruits).
Example: Pine (Pinus).

(v) Angiosperms – Flowering plants with seeds enclosed within fruits.
Example: Mango, wheat, rose.

6. State the difference between chordates and non chordates.

Answer: The difference between chordates and non chordates are :

Chordates	Non-chordates
Notochord is present at least at some stage of life.	Notochord is absent.
Dorsal hollow nerve cord is present.	Ventral solid nerve cord is present.
Pharyngeal gill slits are present at some stage.	Gill slits are absent.
Heart is usually ventral.	Heart is usually dorsal (if present).
Example: Fish, frog, birds, humans	Example: Earthworm, cockroach, snail

7. Name the phyla to which the following belong: wolf, earthworm, sponge, jelly fish, sparrow, butterfly, starfish, snail, tape worm, round worm

Answer: Phyla of the following organisms:

Wolf → Chordata .

Earthworm → Annelida .

Sponge → Porifera .

Jellyfish → Cnidaria .

Sparrow → Chordata.

Butterfly → Arthropoda .

Starfish → Echinodermata .

Snail → Mollusca .

Tapeworm → Platyhelminthes .

Roundworm → Aschelminthes .

8. To which class of chordates do the following belong? Justify your inclusion into the class by stating any one characteristic feature. Crow, lion, cobra, flying frog, shark, fresh water fish.

Answer:

Animal	Class	One Characteristic Feature
Crow	Aves (Birds)	Body is covered with feathers, and they are warm-blooded (endothermic).
Lion	Mammalia (Mammals)	They have mammary glands to nourish their young and have hair on their bodies.
Cobra	Reptilia (Reptiles)	Their skin is dry and covered with scales; they breathe through lungs.
Flying frog	Amphibia (Amphibians)	Their skin is smooth, moist, and without scales. They often have a larval stage (tadpole) in water.
Shark	Chondrichthyes (Cartilaginous Fish)	Their endoskeleton is made entirely of cartilage, not bone.
Fresh water fish	Osteichthyes (Bony Fish)	They have a skeleton made of bone. They also have an operculum (a bony cover) over their gills.

9. Write three sentences on why we need to classify and give scientific names to organisms.

Answer: We need to classify organisms and give them scientific names for the following reasons:

(i) Classification helps us study and understand the vast variety of living organisms in a systematic way.

(ii) Scientific names provide a unique and universal name for each organism, avoiding confusion caused by different local names.

(iii) Classification helps us identify organisms and understand their similarities, differences and evolutionary relationships.

10. Why does biodiversity need to be conserved?

Answer: Biodiversity needs to be conserved because:

(i) It helps maintain the ecological balance and stability of ecosystems.

(ii) It provides important resources such as food, medicines, fuel and raw materials.

(iii) Conservation prevents the extinction of species and protects natural heritage for future generations.

11. State three ways by which biodiversity may be conserved?

Answer: Three ways by which biodiversity may be conserved are:

(i) Protection of natural habitats by establishing national parks, wildlife sanctuaries and biosphere reserves.

(ii) Preventing overexploitation of plants and animals through controlled use of natural resources.

(iii) Afforestation and reforestation to increase green cover and restore damaged ecosystems.

12. List 10 ways in which organisms help each other survive in nature. What message can you derive from their interdependence?

Answer: 10 ways in which organisms help each other survive in nature:

(i) Plants provide food to animals.

(ii) Plants release oxygen needed by animals for respiration.

(iii) Animals release carbon dioxide used by plants for photosynthesis.

(iv) Bees and insects help in pollination of flowers.

(v) Birds and animals help in seed dispersal.

(vi) Decomposers break down dead organisms and return nutrients to the soil.

(vii) Trees provide shelter and habitat to many organisms.

(viii) Predators help control the population of prey organisms.

(ix) Some organisms live in mutual association and help each other (symbiosis).

(x) Microorganisms help in nitrogen fixation, improving soil fertility.
13. Why have some plants and animals become endangered? State atleast five human activities as causes.

Answer: Some plants and animals have become endangered because their population has decreased rapidly due to human activities and changes in their natural habitats, putting them at risk of extinction.

Five human activities causing endangerment are:

(i) Deforestation and destruction of natural habitats.

(ii) Hunting and poaching of animals.

(iii) Pollution of air, water and soil.

(iv) Overexploitation of natural resources for human use.

(v) Industrialisation and urbanisation, leading to loss of biodiversity.

14. Write in a paragraph on "what would happen if living beings did not have scientific names and were not grouped." Mention atleast five consequences.

Answer: If living beings did not have scientific names and were not grouped, it would create many problems in studying and understanding organisms. Different regions would use different local names, causing confusion in identification. Scientists would find it difficult to communicate and exchange information globally. It would become difficult to study similarities and differences among organisms and understand their relationships. Identification of new organisms and their proper study would be complicated. Conservation and protection of biodiversity would also become difficult. Therefore, scientific naming and classification are necessary for systematic study of living organisms.

15. You find some boys pelting stones at a monkey sitting on a tree. Write five sentences which can dissuade those boys.

Answer: (i) Please stop pelting stones at the monkey; it is a living being and can feel pain.

(ii) Hurting animals is cruel and may seriously injure them.

(iii) The monkey is an important part of nature and helps maintain ecological balance.

(iv) If frightened or hurt, the monkey may become aggressive and harm someone in self-defence.

(v) We should be kind to animals and protect wildlife instead of troubling them.

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