NIOS Class 10 Science Worksheet 19 Questions Answers – Classification of Living Organisms

This Worksheet 19 contains questions based on Chapter 19 Classification of Living Organisms with complete answers.

This post explains the answers of questions given in the worksheet including explanation, diagrams. These solutions will help you complete your assignments and TMA also.

 

Classification of Living Organisms Worksheet 19 Solution

Q1. Write the importance of classification and mention the basis of which classification of organisms is based?

Answer

Importance of Classification of Organism

i.    It makes the study of a large variety of living organisms easy and systematic.

ii.   It helps in identifying organisms correctly.

iii. It shows the similarities and differences among organisms.

iv.   It helps us understand the evolutionary relationship between organisms.

v.      It provides a scientific and universal system for studying living beings.

Basis of Classification of Organisms

Organisms are classified on the basis of following features

i.       Type of cell – Two types of cells (i) Prokaryotic (without well formed nucleus) (ii) Eukaryotic (well-formed nucleus)

ii.     Number of cells – Whether organism is unicellular or multicellular.

iii.   Mode of nutrition – Whether organism is autotrophic or heterotrophic.

These bases are used to divide organisms into five kingdoms: Monera, Protista, Fungi, Plantae and Animalia.

 

Q2. Define Biodiversity. State three levels of biodiversity.

Answer  

Biodiversity: - This term is used for the variety of living organisms found on the earth. It includes all plants, animals and microorganism living in different habitats.

Three levels of Biodiversity

i.   Ecological diversity: This refers to the variety of ecosystems such as forests, deserts, rivers, ponds, oceans and mountains on the earth where different kinds of organisms live and interact with their environment.

ii.    Species diversity: - This refers toe the variety of different species of plants, animals and microorganisms present in the particular area. Each species has its own distinct features and cannot interbreed with other species.

iii.  Genetic diversity: - Genes found on chromosomes control the features of a particular species. Every species has a gene pool which has different kinds of genes. The genetic difference cause variations among individuals of the same species.

 

Q3. Name the three domains of life and state one distinguishing feature of each?

Answer

Following are the three domains of life

i.     Archaebacteria (Archaea): - These are heat loving (thermophilic) bacteria that live in extreme conditions such as hot water vents.

ii.   Eubacteria: - These are single celled organisms without a Well-formed nucleus.

 

iii.   Eukarya: - These organisms have a well-formed nucleus. All plants, animals, fungi belong to this domain

 

Q4. State the difference between Chordates and non-chordates.

Answer

Chordates	Non-chordates
Notochord is present at some stages of life	Notochord is absent
Backbone is present	Backbone is absent
Dorsal hollow nerve cord is present	Nerve cord is ventral
Heart is ventrally placed	Heart (if present) is dorsally placed
Example – fish, frog human	Example- earthworm, insect, snail

 

Q5. In which kingdom you will place an organism which is single celled, eukaryotic and photosynthetic? Give the outline classification of Plant kingdom?

Answer

An organism which is single-celled, eukaryotic and photosynthetic is placed in the kingdom Protista. Example – Chlamydomonas

Outline Classification of Kingdom Plantae

   1. Algae – simple plants without true roots, stem and leaves and mostly aquatic and autotrophic. Example- spirogyra

    2. Bryophyta – Plants has no true roots, stem and leaves. They grow in moist places. Example – Moss, Liverwort

   3. Pteridophyta – They have true roots, stem and leaves and reproduce by spores. Examples – Fern

   4. Gymnosperms – Seeds in these plants are naked and not enclosed in fruits. They have no flowers. Examples – Pine, Juniper

   5. Angiosperms – They bear flowers and seeds are enclosed within fruits. Examples – mango

 

Q6. List out the difference between Gymnosperms and Angiosperms.

Answer

Gymnosperms	Angiosperms
Seeds are naked and not enclosed in fruits	Seeds are enclosed in fruits
Flowers are absent	Flowers are present
Ovary is absent	Ovary is present
Evergreen plants with needle like leaves	Plants may be herbs,shrubs, trees
Examples – Pine, cycas, Juniper	Example – Mango, rose

 

Q7. Give the outline classification of animal kingdom.

Answer

Animal kingdom is mainly divided into (i) non-chordates (ii) Chordates

   1. Non- chordates – They are divided into the following phyla

    i.  Porifera – Body with pores. Example – sponge

    ii.    Cnidaria(coelentrata)- Radial symmetry, stinging cells. Exmples- Hydra, jellyfish

    iii.   Platyhelminthes – Flat body organisms. Examples - Tapeworm

   iv.     Aschelminthes – Round body. Example – Roundworm

   v.  Annelida – Segmented body. Example – Earthworm

   vi.   Arthropoda – Jointed legs . examples – insects, spider

   vii.  Mollusca – soft body, shell present in many organisms. Examples – snail, pila

   viii. Echinodermata – spiny skin, radial symmetry. Examples- starfish

   2. Chordates – They are divided into following phyla

   i.              Chondrichthyes – Cartilaginous fishes. Example- shark

   ii.    Oesteichthyes- Bony fishes. Examples- Rohu

   iii.  Amphibia – Live on land and water. Examples- Frog

   iv.   Reptilia- Scales on skin. Example- snake, crocodile

   v.     Aves – Feathers  and wings . example- crow, pegion

    vi.   Mammalia – mammary glands. Examples- human, cow, bat

 

Q8. Give the characteristics of sponge, Tap worms and earthworm. Mention their phylum.

Answer

   1. Sponge

  Phylum- Porifera

  Characteristics

i.     Body has many pores for water passage

ii.   Mostly aquatic and fixed to a surface

iii.  Body is asymmetrical

iv.    No true tissues or organs found

   2. Tapeworm

   Phylum – Platyhelminthes

   Characteristics

i.     Body is flat and ribbon like

ii. Parasitic in nature

iii. No digestive system

iv.  Body is bilaterally symmetrical

    3. Earthworm

   Phylum – Annelida

Characteristics

i.     Body is long, cylindrical and segmented

ii.   Bilateral symmetry

iii. Well-developed digestive system

 

Q9. Why does biodiversity need to be conserved? What do you mean by a hot spot of biodiversity?

Answer

Biodiversity needs to be conserved because:

i.   All living beings are interdependent and maintain balance in nature.

ii.     Plants and algae provide food and oxygen and bacteria and fungi recycle nutrients.

iii.   Destruction of biodiversity disturb food chains and ecosystems.

iv.    Many species of plants and animals are endangered.

v.    Flora and fauna are our natural heritage so they are to be conserved for future generations.

Hotspots of biodiversity

A biodiversity hot spot is a region where a large number of different plant and animal species live.

 

Q10. How organisms are named explain it with an example?

Answer

Organisms are named by a scientific system called Bionomial Nomenclature. This system was introduced by Carolus Linnaeus.

 

In this system, each organism is given a two-word scientific name.

i.     The first word is the Genus name and it starts with a capital letter.

ii.    The second word is ethe Species name and it starts with a small letter.

iii.  The scientific name is written in italics or underlined when handwritten.

iv.  Scientific names are universal and understood all over the world.

Example

Human beings: Homo sapiens

Homo – Genus

Sapiens – species

Mango: Mangifera indica