School Science Health & Physical Education 6

7. Text alignment in a cell
i) Click on a cell with text to be aligned. Click on the Table Layout Tab. Look at

the alignment group to select an alignment option.

ii) Change text direction: Click on a cell containing text to change its direction.
Look at the alignment group under the Layout Tab. Click on text direction to
rotate the text by 90 degrees. Click again to rotate the text by another 90
degrees.

iii) Adjust cell margin: Select a cell/table to adjust margin around the text inside
the cell. Click on 'Cell Margin' icon under the Layout tab to set margin values.

8. Adjust column width and row height

Move the pointer over the border between two rows or columns that you
want to adjust. Arrow gets changed into double headed arrow pointer ( ).
Drag it to adjust the height or width.

Activity

Insert a table of the given format in a word document.

SHREE ………………… SCHOOL Ph. No.
…………………………………………….. email:

(font - Arial black, font size -12)

Students' Individual Progress Record-2078

Name: …………………………………… Class:…………… Sec.:…….

Nepali English Math Science and Social Studies
Technology

S.N. I II I II I II I II I II
Term Term Term Term Term Term Term Term Term Term

Oasis School Science and Technology -6 43

B. Multimedia Uses

Activity

Watch a multimedia presentation. Note the following components of the
presentation. Write about the role each component plays in the presentation.

Text Images Animation Audio Video

Multimedia features help us present the digital information in an attractive form.
Multimedia are a combination of text, graphic, audio, video and animation for
sharing knowledge or information. Text, graphics, audio, video, and animation
are the components of a multimedia application. A PowerPoint presentation with
animated text, audio and video clips is an example use of multimedia features.
Computer, projector, speaker, screen, etc. are required for a multimedia
presentation. Use of multimedia features catches the attention of the audiences.
It increases interest in the learning process.

A multimedia application is necessary to integrate different components as a
multimedia product. For example, Microsoft PowerPoint is an example of a
software to create a multimedia presentation. Filmora is a multimedia software
used for mixing text, audio, video, and animation effects. 'Adobe premiere pro' is
an advanced multimedia software for video editing.

Make a PowerPoint presentation

Activity

Collect images and videos related with simple technological tools and modern
technological tools and store them on your computer's hard disk. Use these to
create a PowerPoint presentation and share your presentation in the classroom.

1. Create a PowerPoint presentation

You can create a new PowerPoint presentation in similar steps that you had
used to create a Microsoft Word document. Create a new presentation and
save it into computer's hard disk.

2. Change layout of a new presentation
i) Click on 'Title and Content' slide layout to change the default layout.

44 Oasis School Science and Technology -6

ii) Click on Title box and add your title 'TITLE'. Similarly, click on content box
to add content 'CONTENT'. You can format font (font family, font size, font
colour, etc.) of the title and content.

3. Insert a new slide
i) Click on 'Home' tab and click on 'new slide' button.
ii) Click on add a new slide to add one new slide. You can add more than one

slide in your need.
4. Choose Theme of your slides
Click on Design tab to select a theme for your slides from the displayed

sample themes.

5. Insert Picture, Audio and Video in your slides
Click on insert menu. Click on picture icon. It displays a picture selection

window. Then select the location of the picture in your computer (e.g.,
Documents). Click on the picture to be inserted. Then, click on insert. Follow
this process to insert audio, and video in your slides, too.

Fact file

Move the pointer to the edge of a picture. The pointer turns into a double headed
shape. Click hold and drag to adjust the size of the picture inserted in your
slide.

6. Add transition to your slides
Transition and animation effects make a presentation attractive. Adding slide

transition makes a slide show interesting as slides appear one after another in
succession with a certain style . For this, you need to select a slide to be given
the transition effect. Click on Transition tab. It displays a number of transition
effects. Click on an icon to select the transition effect (e.g. push).

Oasis School Science and Technology -6 45

7. Run your presentation in a slide show mode
First, click on 'Slide Show' tab to run presentation in slide show mode. Then

click on the 'Start from Beginning' button. Alternatively, press 'F5' button
from keyboard to run presentation in a slideshow mode. Click with mouse to
shift into the next slide. Press escape 'Esc' button from the keyboard to end
the slide show.

C. Spreadsheets

A spreadsheet is a computer application with a grid of columns and rows for
organisation, analysis and storage of data in a tabular form. It is used to calculate
and store numerical data. Data entry changes are easy in an Excel workbook. It
saves time as well as reducing the possible errors in calculation. In schools,
spreadsheets are used to keep students' records, account details, etc. In business,
spreadsheets are used to keep business data records. There are multiple
worksheets in a workbook created with a spreadsheet program. Microsoft Excel,
Google Spreadsheet, LibreOffice Calc, etc. are examples of a spreadsheet
application.
Microsoft Excel Interface

Activity

Run Microsoft Excel on your computer. Create a new spreadsheet document
and save it on the computer's hard disk. Fill your worksheet.

Microsoft Excel Interface

Rows, Columns and Cells: Rows run horizontally across an Excel worksheet.
The heading of a row is marked with a numeric value, that is, 1, 2, 3 ... etc.
Columns run vertically across the Excel worksheet. The heading of a column is
marked by a letter of the alphabet, that is, A, B, C, … etc. A cell is the intersection

46 Oasis School Science and Technology -6

of a row and a column in the worksheet. Every cell has its unique address. The
cell address is the combination of the 'column letter' and 'row number' at the
intersection of the particular row and column. For example, the address of a cell
at the intersection of 'column A' and 'row 1' is A1.
1. Filling data in a spreadsheet
First, select a cell. Type content into the selected cell. Press enter from the

keyboard to insert content. Use keyboard arrows ( ) to shift cells in your
worksheet. Double click on the cell to edit content in it.
2. Auto fill content using fill handle

Fill handle is a small square at lower right corner of a cell. Fill a number in a
cell. Move pointer over the fill handle. Observe the change in white cross ( )
into black cross (+) as shown in the figure. Click, hold and drag down in
column to copy the same content throughout the range.

To fill data in a sequential order
Move white cross over fill handle and press control. Observe a small plus over
black cross. Click with control button, hold and drag to fill a series.

Cell, Column, and Row selection
Click on the first cell, hold, and drag the mouse up to the last cell. Release the
mouse to select the desired cell range (e.g. A2:D2 or B2:C4).
To select whole column
Move the pointer over heading of the column. Observe the change in white cross
( ) into dark down arrow ( ). Click with down arrow to select whole column.
Delete cell content
Select the cell or cell range which consists of the content to be deleted. Press

Oasis School Science and Technology -6 47

'Delete' key on your keyboard. It deletes the content in the selected cell or cell
range.
Adjust width of a column
Sometimes our data entry does not fit inside the cell boundary. In such a case, we
need to adjust the column width. Following steps adjust the column width:
Place the mouse pointer over the column line in the column
heading. Observe the change in white cross ( ) into double
arrow ( ) as shown in the figure. Click, hold, and drag the mouse
to adjust the column width. We can double click on the column line when the
white cross gets changed into double arrow. It adjusts the width automatically
up to content limit.
Merge cells in a worksheet
First select the cell range to be merged in to a single cell. Select 'Home' Tab. Click
on 'merge and center' command button. All cells get merged into one and the
content gets centered.
Sort Data in a worksheet

Activity

Collect the marks of students from your class records. Fill the data in a worksheet.
Follow the given steps to sort the data alphabetically as well as on the merit
basis.
i) Select a cell in the column with the data you want to sort.
ii) Click on Data tab. Then look for 'Sort & Filter group'.
iii) Click on ascending command to sort the data in an ascending order (A to Z).
Or, Click on descending command to sort the data in a descending order (Z to A).

48 Oasis School Science and Technology -6

Summary

1. A computer is an electronic device that accepts input data and processes the
data to give the output.

2. Input (I) is an instruction given to a computer.
3. The device through which data and instructions enter a computer is called an

input device. For example, keyboard, mouse, etc.
4. Output (O) is the result shown after processing the data that the computer

receives in the form of input.
5. An output device is a part of a computer that presents the processed data to

the user. For example, display screen, speaker, etc.
6. A word processor is a computer program to create, edit, and format documents

such as letters, forms, tables, reports, handouts, etc.
7. Multimedia presentations are combinations of text, graphic, audio, video and

animation features for sharing knowledge/information effectively.
8. Spreadsheet is a computer application with a grid of columns and rows for

organisation, analysis and storage of data in a tabular form.

Exercise

1. Fill in the blanks with appropriate words.
(hardware, brain, word processor, smartphone, software, IPO)
a. A computer works on …………… principle.
b. CPU is ……….. of a computer.
c. A computer ……………. cannot function without a …………. .
d. …………. connected with internet can be used to access bank accounts.
e. A ……………… is used to compose letters using computer.

2. Write True for the correct and False for the incorrect statements.
a. A printer is an input device.
b. A computer accepts input and processes it to give output.
c. We need to maintain a proper distance from the computer screen.

Oasis School Science and Technology -6 49

d. Worksheet is a grid of columns and rows.
e. Physical parts of a computer are called software.

3. Select the best answer from the given alternatives.

a. A computer works on the principle of:

i. Input, Output, Process ii. Output, Input, Process

iii. Input, Process, Output iv. Process, Input, Output

b. Prolonged computer and smartphone use can create a vision problem of:

i. Blurred vision ii. Dry eyes

iii. Headache iv. All of the above

c. The full form of CPU is iii. Central process unit
i. Center process unit iv. Center processing unit
iii. Central processing unit

d. Identify a multimedia application.

i. MS windows ii. MS excel

iii. MS word iv. MS PowerPoint

e. Which one is the correct set of output devices? shown below and
i. mouse, printer, speaker, scanner
ii. scanner, projector, microphone, display screen
iii. monitor, projector, speaker, printer
iv. mouse, printer, hard disk, camera
4. Figures based questions

a. Observe the figures of digital devices
answer the given questions.

b. Write the names of the devices shown above.
c. What are the two common features in all of these devices?
d. Write two specific features of each of them.

50 Oasis School Science and Technology -6

e. Look at the data filled in a worksheet. Write the steps to sort the
numerical data from the largest value to the smallest value. Make a table
to show the corresponding result after sorting the data.

Name Marks
Rajaram 12
Narayan 8
Kedar 15
Unish 18

5. Answer the following questions.
a. What is a computer?
b. Explain the working principle of a computer in short.
c. Write an example each of an input device, output device, processing
device, and storage device.
d. Why are Smartphones, iPads, and Tablets also called a type of computer?
e. Write two differences between input devices and output devices.
f. Write four uses of computers in different sectors.
g. Write any four specific uses of smartphones.
h. Write the steps to compose a letter using MS word.
i. Explain in short about your preparation and procedure to make a
PowerPoint presentation. How will you present it to your classroom?

j. Make a list of different types of computers.

k. Write two important things to be remembered while using computers
and smartphones.

l. You are asked to fill students’ marks in tabular form using a computer.
Which computer program (software) will you use? Write the
corresponding steps involved.

m. What is multimedia? Explain its uses in short.
n. Why is the use of multimedia preferred in classrooms?

Oasis School Science and Technology -6 51

3Unit Organisms and Estimated Teaching Periods:
Their Structure
Theory Practical
11 4

3.1 Adaptation of organisms 3.2 Classification of animals on
the basis of food

3.3 Invertebrates 3.4 Flowering and non-flowering plants

We see a variety of animals and plants in our surroundings. They are different in
their structure, size, shape, colour, habit and habitat. Some animals and plants
are big, others are small. Some animals and plants live on land, others live in
water. Some animals eat plants, others eat animal flesh. Some eat both plants and
flesh. Some live in a hot climate, others live in a cold climate.

3.1 Adaptation of Organisms

Topics in Their Order according to CDC Curriculum
1. Introduction to adaptation of organisms
2. Adaptation features of aquatic animals and their organs
3. Adaptation features of terrestrial animals and their organs
4. Adaptation features of aquatic plants and their parts
5. Adaptation features of terrestrial plants and their parts

52 Oasis School Science and Technology -6

Learning outcomes

At the end of this unit, students will be able to:
1. Identify adaptation features of animals and plants.
2. Identify important parts of animals and plants.

Key terms of the unit

Habitat: The place where animals and plants born, grow and develop is called their
habitat.

Adaptive features: The unique features of plants and animals that enable them to live
in a particular environment are called adaptive features.

Adaptations: The process by which organisms adjust to their own environment due to
some adaptive features is called adaptations.
Aquatic animals: Some animals live in water. They are called aquatic animals.

Marine animals: Animals that live in sea and ocean are called marine animals.

Terrestrial animals: Animals that are adapted to live on the land are called terrestrial
animals.

Cursorial animals: The animals which can run fast on the ground are called cursorial
animals.

Arboreal animals: Animals that are adapted to spend most of their life on trees are
called arboreal animals.

Aerial animals: The animals that are adapted for flying mode of life are called aerial
animals.

Desert animals: Animals that are adjusted in dry and hot climate are called desert
animals.

Polar animals: Animals that are able to live in cold polar region of the earth are known
as polar animals.
Aquatic plants: Some plants like watergrow in water. They are called aquatic plants.

Terrestrial plants: We see many kinds of plants grown on land around. They are called
terrestrial plants.

Xerophytes: Plants that are adapted to live in deserts are called xerophytes or desert
plants.

Creepers: Some plants can’t stand erect like maize, banyan or other terrestrial trees.
They are called creepers.

Climbing plants: Plants that are adapted for climbing over external support for their
growth are called climbing plants or climbers.

Oasis School Science and Technology -6 53

Habitat

Organisms have specialised body features that help them live in their environment.
For example, the body structure of fish and aquatic plants enables them to live in
water. Terrestrial animals such as cows, buffaloes, deer, elephants, birds, dogs,
etc. live on land. Their body structure enables them to survive on land. The place
where animals and plants are born, grow and develop is called their habitat.
They adapt themselves to live and grow in their habitat and environment.

Adaptation

Organisms adjust themselves to their habitat. Their specialised body structures
help them make the necessary adjustments. Their bodies are built to help them
find food and water, protect themselves, cope with the difficulties in their
environments and engage in reproduction. The unique features of plants and
animals that enable them to live in a particular environment are called adaptive
features. The process by which organisms adjust to their environment with the
help of their adaptive features is called adaptation.

Activity

Observe the adaptive features of organisms given in the table and discuss
these features with your friends. Name at least two organisms and their
habitats found in your surroundings.

S.N Adaptive Features Animal Habitat

1 Sharp claws and strong paws in the limbs Tiger, Lion Grasslands
Feed on the flesh of other animals

2 Fore limbs are modified into wings
Have hollow spongy bones in their body

3 Breathe through gills
Limbs are modified into fins

4 Long, slender and strong limbs fit for running
Feed on plants

5 Creep on land
Rough and dry skin with scales

6 Leaves are modified into thorns/ spikes
Green fleshy stem to store water

54 Oasis School Science and Technology -6

Classification of animals on the basis of adaptation

Some animals live in water and others live on land depending on their ability to
adapt to the environment. Based on their adaptive features, animals are classified
into two groups: aquatic and terrestrial.

Aquatic animals

Animals such as fish live in water, which is aqua in Latin. So they are called
aquatic animals. They have special features that help them survive in water.
Animals that live in fresh water such as a river, lake, pond, spring etc. are called
fresh water animals. Examples are a trout, eel, crocodile and carp. Similarly,
animals that live in the sea and ocean are called marine animals. Some examples
of marine animals are the octopus, shark, seal, sea horse, starfish, whale, etc.

Adaptive features of aquatic animals

Aquatic animals have special features in their body. For example, fins, gills, air
bladder and scales. Their boat-shaped body makes it easy for them to float on
water. Gills help the fish breathe inside water. However, crocodiles, salamanders,
frogs, dolphins etc. breathe through their lungs. Some animals have scales
covering their body to protect them from external injuries and predators. Fins
and webbed feet help aquatic animals with swimming. Fish have caudal fin (tail)
that helps them change the direction while they are moving. Some aquatic animals
have an air bladder in their body. The air bladder maintains water pressure while
the animals are swimming at different depths.

carp trout fish dolphin shark

seal whale silverfish octopus

Oasis School Science and Technology -6 55

Activity

Observe the adaptive features of a frog and a fish. Name their organs that are
modified for such adaptation.

fish frog

S.N Features Frog Fish
Moist skin
1 Protects from external scales

injuries and predators ……………

2 Hopping on land and Hind limbs and fore ……………
limbs ……………
swimming in water

3 Breathing in land and water ……………

4 Shape of body for floating in ……………

water

Terrestrial animals

Animals such as lions, tigers, deer, bears, rabbits, horses, dogs, cats, sparrows,
crows, eagles, parrots, camels and polar bears live on land. They are called
terrestrial animals. Animals that have adaptive features to help them live on land
are called terrestrial animals. Different terrestrial animals have different adaptive
features, habits and habitats. On the basis of the adaptive features, the terrestrial
animals can be classified as cursorial, fossorial, arboreal, aerial and desert animals.

Cursorial animals

Animals such as deer, wild buffaloes, lions, tigers, dogs, leopards, kangaroos,
horses and zebras have the ability to run on land. They are cursorial animals.
Animals that can run on the ground fast are called cursorial animals. Herbivorous
cursorial animals have long and slender limbs with hoofs for running. They also

56 Oasis School Science and Technology -6

have flat jaws for chewing plants. Carnivorous cursorial animals have strong
paws with sharp claws for hunting and running. They also have sharp canines
(teeth) to pierce and tear through the flesh.

kangaroo deer zebra tiger

Arboreal animals

Some animals are adapted to trees where they spend most of their life. They are
arboreal animals. Monkeys, lizards, chameleons, squirrels, sloths etc. are some
examples. Animals that are adapted to spend most of their life on trees are called
arboreal animals. Arboreal animals have a semicircular body with curved ribs
which enables them to climb trees. They have strong chest muscles that support
their swings from branch to branch. Lizard and chameleon have an adhesive pad
in their limb which holds them on hard vertical surfaces.

monkey squirrel lizard chameleon

Aerial animals

Birds spend most of their time flying in the sky. Sparrows, pigeons, crows, owls,
eagles and vultures are examples of birds. The animals that have adapted to the
flying mode of life are called aerial animals. Aerial animals have a streamlined
(boat shaped) body that decreases air resistance during their flights. Their fore
limbs are modified into wings which help them fly. They have a light body
because of the hollow and spongy bones that form their skeleton. They also have
air sacs in their body which further help them float in the air. Their body is
covered with fluffy feathers. Their teeth are modified into beak. Grain and insect
eaters have a small pointed beak while carnivores such as eagles have a sharp
curved beak. Birds such as swan and duck have flat beaks to catch fish.

Oasis School Science and Technology -6 57

sparrow crow eagle duck

Adaptation in desert animals

Deserts are extremely hot in the daytime and extremely cold at night. Some
animals have adjusted to the desert climate: camels, snakes, desert foxes, kangaroo
rats, etc. Animals that have adapted to dry and hot climates are called desert
animals. Camels have a hump in their body which stores food materials for a
long time. They also have a thick and dry skin that checks the loss of water from
their body. Camels can also store water in their specialised tissues. They urinate
less frequently. These adaptive features prevent their dehydration. Camels have
strong leg muscles and hoofs to walk on sand. Some desert animals get active at
night to avoid the extreme heat of the day.

camel snake kangaroo scorpion

Adaptation in polar or cold animals

Arctic regions, polar areas and high mountains are extremely cold. Animals such
as snow leopards, Himalayan bears, yaks, walrus, arctic foxes, ringed seals, arctic
wolfs, harp seals, arctic hares, bearded seals and snow owls live in such cold
climates. They are known as polar animals. Animals that are able to live in cold
polar regions of the earth are known as polar animals. Their body is covered with
thick fur on the skin and a thick coat of fat below the skin to keep them safe from
cold.

yak polar bear arctic fox seal

58 Oasis School Science and Technology -6

Adaptation of plants

On the basis of their habitat, plants are also classified into two major groups:
aquatic and terrestrial.

Adaptation in aquatic plants

Plants such as water lilies, algae, duck weeds, hydrilla, lotus and water hyacinth
grow in water. They are called aquatic plants. Most of the aquatic plants have soft
and spongy stems. They have floating leaves. The body of most aquatic plants is
covered with waxy substances to avoid their decay in water. Aquatic plants have
a weak root system as they absorb water easily.

duckweed water hyacinth hydrilla lotus

Activity 3

Visit a nearby pond with your teacher or guardian and note down the local
name and body features of at least three aquatic plants.

S.N Common Name or Root Stem Leaves
Local Name
Rooted in soil Spongy and Flat and
1. Lotus slender floating

2.
3.
4

Terrestrial plants

We see a variety of plants on the land around us. Examples are paddy, maize,
barley, wheat, pine, deodar, cedar, spruce, fir, peepal, banyan, mango, sal,
banana, guava, orange, lemon, palm, coconut, ashoka and rubber. These plants
are known as terrestrial plants.

Oasis School Science and Technology -6 59

fern mucor moss mushroom

sal tree ashoka tree coconut tree mango tree

Adaptation in xerophytes or desert plants

Plants that are adapted to live in deserts are called xerophytes or desert plants.

Desert plants can adjust themselves to hot environments. Aloe, opuntia, cactus,
agava etc. are examples of xerophytes. They have fleshy and green stems to store
water and carry out photosynthesis. Some desert plants have deep roots to absorb
water and minerals. Xerophytes have spiny and thorny leaves to reduce the loss
of water.

opuntia cactus aloe agava

Adaptation in cold climate plants

Some plants grow in extreme cold. Pine, fir, deodar, cycas, spruce etc. are adapted
to cold climates. They look like inverted cones in shape. They have hard and
woody stems with short branches. They bear cones instead of flowers. They have
long needle-shaped leaves that allow the snow, mist and rainfall to slip down
easily.

60 Oasis School Science and Technology -6

pine tree fir tree spruce tree cycas tree

Adaptation in creeping plants

Some plants cannot stand on their own as they grow. They are called creepers.
Creepers have fragile, long and thin stems. These stems cannot stand straight
and support their own weight. They have adapted to creeping on the external
support they find on the ground. Watermelon, strawberry, sweet potatoes,
pumpkin etc. are examples of creepers.

watermelon strawberry sweet potatoes pumpkin

Adaptation in climbing plants

You might have seen the pea, gourd, grapevine, money plant and runner bean in
your surroundings. These plants are called climbing plants. They have thin, long
and weak stems which cannot to grow upright without external support. But
they have special structures called tendrils which help them climb over the
support as they grow. Plants that are adapted to climbing over external support
for their growth are called climbing plants or climbers.

pea plant gourd plant grapevine plant money plant

Oasis School Science and Technology -6 61

Project Work

Observe 5 plants and 8 animals found in your surroundings. List their body
features and functions.

S.N. Plants Body feature Function

1 Pine (Sallo) Needle-shaped leaves Reduce water loss and help mist,
dew and snow flow downward

2
3
4

S.N Animals Body feature Function
1 Mosquito
Proboscis Sucks fruit juice and blood from
mammals

Exercise

1. Select the best alternatives from the given options.

a. Thorns in the cactus are the modified form of

i. stem ii. leaf iii. branch iv. flower

b. Rat is an example of

i. cursorial animal ii. fossorial animal

iii. aerial animal iv. arboreal animal

c. Which is a hydrophyte?

i. water hyacinth ii. lily iii. coconut iv. pine

d. It grows in moist and shady environment.

i. mango ii. rubber iii. mushroom iv. cactus

e. Fore limbs of aerial animals are modified into

i. feathers ii. wings iii. beak iv. claws

62 Oasis School Science and Technology -6

2. Write True for correct and False for incorrect statements.
a. A habitat is a home for organisms to live.
b. The jaws of zebra are adapted for eating grass.
c. Eagles have sharp and strong claws for holding their prey.
d. Cactus is an aquatic plant.
e. Hydrophytes have fleshy stem.

3. Fill in the blanks with appropriate words.
a. ……………………. is a fresh water animal.
b. Carnivorous cursorial animals have strong ….. and sharp …….. for
hunting.
c. …………………… has adhesive pad in its limbs to hold and crawl on
vertical surfaces.
d. Floating plants have ……………….. leaves and spongy stem.
e. ………………….. is a xerophyte whereas …………………. is a
hydrophyte.

4. Match the following:

Cursorial Animals adapted to flying
Fossorial Plants adapted to deserts
Arboreal Animals adapted to running
Aerial Plants adapted to water
Xerophytes Animals adapted to living in trees
Hydrophytes Animals adapted to living in burrows

5. Write your answer to the following questions in a word each.
a. What is another name of aquatic plants?
b. Write an example of a carnivorous aerial animal.
c. The process in which the organisms fit in with the particular
environment.
d. Another popular name of desert plants.
e. Which animal has a hump in its body?

Oasis School Science and Technology -6 63

6 Write two differences between:
a. Camel and yak

b. Hydrophytes and xerophytes

c. Aquatic and terrestrial animals

7. Give reason:
a. A deer adapts to an arboreal mode of life.

b. Hydrilla is called a hydrophyte.

c. Lizard has adhesive pad in its limb.

d. Leaves of cactus are modified into spines.

8. Define the following terms:

a. Adaptation b. Adaptive features

c. Aquatic animals d. Terrestrial animals

e. Hydrophytes f. Xerophytes

g. Climbers h. Creepers

9. Answer the following questions.

a. Write any three features of an eagle whihc enable it to adopt a flying
mode of life.

b. List any three adaptive features of a leopard.

c. What features make fish fit to live in water? Write any four.

d. List the adaptive features of hydrilla.

e. Write any three features of a camel that enable it to adapt to living in a
desert.

64 Oasis School Science and Technology -6

3.2 Classification of Animals
on the Basis of Food

Topic according to CDC Curriculum

1. Characteristics and examples of herbivores, carnivores and omnivores.

Learning outcomes

At the end of this unit, students will be able to:
1. Classify animals on the basis of food with examples.

Key terms of the unit

Herbivores: Animals that eat plants parts of plants are called herbivores.
Carnivores: Flesh eating animals are known as carnivores.

Omnivores: Animals that eat both plants and flesh of other animals are called
omnivores.

Animals need food. Food gives them the energy to live. Different animals eat
different types of food. Some animals eat only plants and their parts. Some
animals eat only the meat, or flesh, of other animals. Some animals eat both plants
and animal flesh.

Activity

List the names of some organisms found in your locality. Note their habitat
and food.

S.N Living Organisms Habitat Food

1 Mushrooms Moist shady places Decayed plants and
animal parts
2 Grasshoppers Grassland
leaves

Classification of animals

On the basis of the food they eat, animals are classified into three categories:
herbivores, carnivores and omnivores.

Oasis School Science and Technology -6 65

Herbivores

Animals such as a cow, goat, buffaloe, horse, pigeon, parrot, rabbit, deer, giraffe
and kangaroo eat only plants and parts of plants. These are called herbivorous
animals, that is, hebivores in a word. Animals that eat only plants and their parts
are called herbivores. Grass eating animals have flat jaws for chewing. They also
have a longer digestive tract for the digestion of food.

humming bird giraffe deer cow

Carnivores

There are some animals which eat only the flesh, or meat, of other animals.
Examples are snakes, eagles, vultures, hawks, tigers, lions, leopards, spiders,
frogs, etc. Flesh or meat eating animals are called carnivores. They don’t eat
plants and products of plants. They have specialised body features to catch their
prey. Lions and tigers have sharp teeth and powerful jaws to kill their prey.
Chameleons and some frogs have long sticky tongues to catch the prey. Snakes
and spiders use venom to kill their prey. Carnivorous birds like eagles and hawks
have sharp claws to catch their prey and curved and pointed beaks to tear the
flesh. Pythons catch their prey, tie the victim around with their long body and kill
it for food.

spider frog snake eagle leopard

Omnivores

Animals such as dogs, crows, sparrows, bears, pigs, cats and humans eat both
plants and flesh of other animals to survive. Animals that eat both plants and
flesh of other animals are called omnivores. Omnivores such as bears and human
beings have special kind of teeth that help them eat both plants and flesh of other
animals. Birds such as crow have a sharp and pointed beak to help them pick a
variety of food. Canines of omnivores help them with tearing flesh while their
flat jaws help them with grinding and chewing grains. They have a digestive
tract suitable to digest both plants and animal meat.

66 Oasis School Science and Technology -6

crow pig bear human

Fact file

Animals that take dead and decayed animals and plants as their food material
are called detrivores. Examples are vultures and crabs. They are the sweepers
of the environment.

Fig.: vulture

Exercise

1. Fill in the blanks with suitable words.
a. All animals need …………… to continue their life.
b. A dog is an …………… because it eats both plants and flesh of animal.
c. Herbivores have longer ……………… tract than that of carnivores.
d. Animals that eat plants or products of plants are called ………………..
e. The leopard is an example of …………………….

2. State whether the following statements are true or false.
a. Animals eat food to get energy.
b. Omnivores can also have canine teeth for tearing flesh.
c. Rats are omnivores in their wild habitat.
d. Cows and buffaloes have flat jaws for chewing plants.

Oasis School Science and Technology -6 67

e. Tigers have a very long digestive tract.

3. Write your answer to the following questions in a word each.
a. Name an insect that feeds on grass.
b. Name an animal that is a carnivore in nature and an omnivore as a pet.
c. Write the name of an animal with flat jaws for chewing plants.
d. Name a bird with sharp claws and a curved pointed beak that tear the
flesh?
e. What is the name of the tooth that is used for the tearing the flesh?

4. Write down any two differences between:
a. Carnivores and herbivores
b. Omnivores and carnivores
c. Dog and cow

5. Give reasons:
a. A dog is an omnivore.
b. A lion is a carnivore.
c. A rabbit is a herbivorous animal.
d. A bear is an omnivore.

6. Identify herbivores, carnivores and omnivores.



7. Define the following terms:

a. Herbivore b. Carnivore c. Omnivore

8. Answer the following questions.
a. What are herbivores? Write down the adaptive features of herbivores.

b. Write some characteristics and examples of carnivores?

c. What similarities and differences do you see between a cat and a
tiger?

68 Oasis School Science and Technology -6

3.3 Vertebrates

Topic according to CDC Curriculum

1. Characteristics and examples of pisces, amphibians, reptiles, aves and
mammals

Learning outcomes

At the end of this unit, students will be able to:
1. Classify vertebrates.
2. Identify some characteristics and examples of different classes of vertebrates.

Key terms of the unit

Vertebrates: Those animals which have backbone in their body are called
vertebrates.
Pisces: Pisces are the animals that live in water.

Amphibians: The vertebrates that can live both in water and on land are called
amphibians.

Reptilians: Reptilians belong to the class of vertebrates that move from one
place to another by crawling.

Aves: Aves are warm blooded flying animals.

Mammals: Mammals are warm bloodedanimals. They have mammary glands
and suckle their babies.

Introduction

Animals such as cows, buffaloes, human beings, fish, frogs, tortoises, birds and
dogs have backbones. They are called vertebrates. Animals which have
backbones in their body are called vertebrates. Most vertebrates live on land,
but some live in water, too. They have well-developed body organs and body
systems: the respiratory system, digestive system, reproductive system,
circulatory system and nervous system.
On the basis of their structure and development, vertebrates are divided into five
different classes. They are Pisces, Amphibia, Reptilia, Aves and Mammalia.

Oasis School Science and Technology -6 69

Pisces

Pisces are animals that live in water. All fish fall in this category. Some examples
of Pisces are salmons, sharks, sea horses, eels, carps and ray fish. They are
cold-blooded animals. Their body is usually streamlined and boat-shaped. They
have the head, trunk and tail. They have fins for swimming and tails for changing
their direction of movement. They have the gills for respiration.

Fact file

Pisces and Amphibia engage in external fertilisation. They release their sperm
and eggs in water, where fertilisation occurs, outside the female body.

Fact file

Pisces have two chambers in their heart.

carp shark sea horse ray fish

Amphibia

The vertebrates that can live both in water and on land are called amphibians.
Frogs, salamanders and toads are examples of amphibians. They are cold-blooded
animals. Their body is divided into head and trunk. They have two pairs of limbs
for movement. Their hind limbs are longer and stronger than the fore limbs. They
have moist skin with glands. Their breeding occurs in water.

frog salamander toad

Fact file

Amphibians and reptiles have three chambers in their heart.

70 Oasis School Science and Technology -6

Reptilia

Reptilians belong to the class of vertebrates that move from one place to another
by crawling. They are cold-blooded animals. They have a head, neck, trunk and
tail in their body. Some examples of reptiles are snake, crocodile, turtle and lizard.
These animals breathe through lungs. Their skin is dry and rough without glands.
Except snakes, all reptiles have well-developed ears. Their fertilisation is internal.
They are oviparous and their eggs are very yolky.

snake crocodile lizard turtle

Fact file

Reptiles were the first class of organisms to adapt to land. They developed from
the amphibians.

Aves

Aves and mammals have four chambers in their heart.

Birds such as parrots, pigeons, eagles, sparrows and crows are flying animals.
Most of them can fly in the sky. But some birds cannot fly. Birds have feathers
and toothless beaked jaws. They lay eggs. They have four chambers in their heart.
Their skeletons are strong but light. Birds are warm-blooded animals. Their fore
limbs are modified into wings. Their hind legs are adapted for walking, hopping,
resting, grasping, wading and swimming. Birds have a sharp eyesight. All the
birds are oviparous (lay eggs).

pigeon hen ostrich parrot

Oasis School Science and Technology -6 71

Fact file

Bats also fly like birds, but they are not birds. They are mammals. They are
known as flying mammals.

Mammalia

Animals such as cows, buffaloes, horses, elephants, whales, dolphins, hippos,
cats, rats, dogs and humans are mammals. They have a bodily system for internal
fertilisation and give birth to babies. They feed their milk to their young ones.
Mammals are warm blooded. The body of terrestrial mammals is covered with
hair. They have limbs for movement. But aquatic mammals have adapted their
limbs to paddle for swimming. Mammals have teeth to catch or chew food. They
have a four-chambered heart and respire through lungs.

woman cat rat dog

bat whale dolphin cow

Activity

i. Observe your surrounding areas and list five animals of each class.
ii. Write any three features of each class of animals.

iii. Make a drawing of each of these animals on a paper, label them and show
the sketches to your teacher.

72 Oasis School Science and Technology -6

Exercise

1. Tick () the correct statement and cross (×) the false one.
a. Aves engage in external fertilization.
b. Mammals have four chambers in their heart.
c. Vertebrates have vertebral columns.
d. Jelly fish is an example of a vertebrate.

e. Amphibians have a horny and rough skin.

2. Fill in the blanks with appropriate words.
a. Crocodile belongs to the ………… class.

b. Whales belong to the………… class.

c. Bats reproduce giving ……………….

d. The body of fish is covered with ………………

e. Amphibians can live both on………..and in……..

3. Match the following:

An example of Mammal ( ) Snake
An example of Amphibia ( ) Salmon
An example of Reptile ( ) Ostrich
An example of Aves ( ) Vertebral column
Vertebrates have ( ) Bat
An example of Pisces ( ) Toad

4. Tick () the best answer from the given alternatives.

a. Which of the following is a cold-blooded animal?

i. frog ii. parrot iii. rabbit iv. monkey
iv. dolphin
b. Which of the following is a cold-blooded animal? iv. pisces
iv. crocodile
i. lizard ii. duck iii. whale

c. The body of ……….. is covered with hair.

i. mammals ii. aves iii. reptiles

d. Which of the following is a reptile?

i. bat ii. whale iii. rat

Oasis School Science and Technology -6 73

e. Which of the following is a viviparous animal?

i. snake ii. turtle iii. lizard iv. whale

5. Differentiate between: b. Horse and Sea horse
a. Bat and Pigeon

c. Invertebrates and Vertebrates d. Lizard and Frog

6. Give reason:
a. The snake is grouped in the class reptiles.
b. Frogs carry out external fertilization.
c. Whale is a mammal.
d. Bat is a viviparous animal.

7. On the basis of each of the given features, name an organism.
a. It has hollow and light bones.
b. It has mammary glands in its body.
c. It has fins and tail for locomotion.
d. It has sticky and rolling tongue to catch the prey.
e. It has horny scales over its body.

8. Name the class and write down any two features of each.


9. Answer the following questions.

a. Define vertebrates with any four examples.
b. What are Amphibians? Write down any three salient features and three

examples of Amphibians.
c. What are Reptiles? Write down any three salient features and three

examples of Reptiles.

d. What are Aves? Write down any three salient features and three
examples of Aves.

e. What are Mammals? Write down any three salient features and three
examples of Mammals.

f. What are Pisces? Write down any three salient features and three
examples of Pisces.

74 Oasis School Science and Technology -6

3.4 Flowering and Non-Flowering Plants

Topics in Their Order according to CDC Curriculum

1. Introduction to flowering and non-flowering plants
2. Differences between flowering and non-flowering plants

Learning outcomes

At the end of this unit, students will be able to:
1. Identify flowering and non-flowering plants.
2. State their similarities and differences.

Key terms of the unit

Flowering plants: The plants that bear flowers are called flowering plants.
Non-flowering plants: The plants that don’t bear flowers are called non-
flowering plants.
Thallophytes: Those plants whose body cannot be divided into roots, stems
and leaves (thallus body) are known as thallophytes.
Algae: Green plants whose body cannot be divided into roots, stems and leaves
are called algae.
Fungi: Non-green plants whose body cannot be divided into roots, stems and
leaves are called fungi.
Bryophytes: Plants with flat, green and leafy body without distinct roots, stems
and leaves are called bryophytes.
Pteridophytes: Non-flowering plants with distinct roots, stems and leaves are
called pteridophytes.
Gymnosperms: The plants having naked or open seeds are called gymnosperms.
Angiosperms: Flowering plants with closed seed are called angiosperms.
Monocotyledonous: Plants that have only one cotyledon in their seed are
known as monocotyledonous plants.
Dicotyledonous: Plants having two cotyledons in their seed are called
dicotyledonous plants.

Oasis School Science and Technology -6 75

Plants can be placed in two groups depending on whether they flower or not.
So, we have flowering and non-flowering plants. The plants that bear flowers are
called flowering plants. Their examples are rose, lily, apple, maize and pear. The
plants that don’t bear flowers are called non-flowering plants. They are fern,
moss, etc.

Activity

Visit a nearby garden and observe the flowering and non-flowering plants.
List their names and external features such as leaf, root, stem and flower.

Plants Root Stem Leaves Flower
Mushroom No No No No
Algae
………. ……… ……… ……… ………

Non-flowering plants (Cryptogams)

Plants that do not bear flowers are known as non-flowering plants (cryptogams).

Cryptogams

Thallophytes Bryophytes Pteridophytes
(e.g. moss) (e.g. fern)

Algae Fungi
(e.g. pondscum) (e.g. moulds, mushroom)

Non-flowering plants (Cryptogams) are flowerless and seedless plants. These
plants bear no flower, fruit and seed. Plants such as algae, mucor, moss,
mushroom, and fern belong to cryptogams. They are further subdivided into
three divisions as Thallophyta, Bryophyta and Pteridophyta.

76 Oasis School Science and Technology -6

Thallophyta

Plants whose body cannot be divided into roots, stems and leaves (thallus body)
are known as thallophytes. For example, algae, mucor, moss, mushroom, fern,
etc. They have the following features:

a. Thallophytes are usually found in moist or wet places.

b. They don’t have vascular tissues.

c. They are autotrophic (primary producer) in nature. Starch is their reserve food.

d. They have a single cell reproductive organ.

Green thallophytes (algae)

Green plants whose body cannot be divided into roots, stems and leaves are
called algae. They are mostly found in aquatic environments. Algae have
chlorophyll in them so they prepare their food by themselves. Examples of algae
are spirogyra, hydrilla, chlamydomonas and ulothrix.

spirogyra hydrilla chlamydomonas

Non-green thallophytes (fungi)

Non-green plants whose body cannot be divided into roots, stems and leaves are
called fungi. They are found in moist habitats. They lack chlorophyll. Therefore,
they get their food from outside, that is, from the dead and decayed matters.
Examples of fungi are yeast, mucor and mushroom.

mushroom mucor

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Bryophyta

Bryophytes are a simple form of non-flowering terrestrial plants found in damp
places. They have a flat, green and thallus body. Thus, plants with flat, green and
leafy body without distinct roots, stems and leaves are called bryophytes. For
example, mosses, marchanita, etc. Hair-like structures called rhizoids help them
stand erect on the ground.

moss marchantia

Pteridophytes

Pteridophytes are the most developed among cryptogams. They are vascular
plants. Thus, non-flowering plants with distinct roots, stems and leaves are called
pteridophytes. Examples of pteridophytes are ferns, horsetails and lycopodium.

Activity

Have you seen the fern? Have you heard of or eaten Niguro and Daude as
vegetables? If not, take a note that the young leaves of fern are also eaten as a
vegetable. Based on your observation or experience, share the features of fern
with your friends.

Flowering plants (Phanerogams)

Plants that bear flowers in them are known as flowering plants or phanerogams.
They are also called seed-bearing plants as they produce seeds.

Phanerogams or Spermatophytes

Gymnosperms Angiosperms
(e.g. pine, cycad) Monocotyledons
(e.g. paddy, grass)
Dicotyledons
(e.g. pea, mango)
78 Oasis School Science and Technology -6

The seeds give birth to new plants after germination. Some examples of flowering
plants are apples, mangoes, guavas, coconuts and peas. Flowering plants are
placed in two divisions: gymnosperms and angiosperms.

Activity

List the names of some flowering plants found in your school or home. Discuss
how they are similar and different from one another.

apple tree mangoe tree guavastree pea plants coconut tree

Gymnosperms

Gymnosperms are seed-bearing flowering plants. They do not yield fruits. Thus,
the plants having naked or open seeds are called gymnosperms. For example,
pine, fir, cycas, etc. They bear cones instead of a true flower. They have long and
needle-shaped leaves. They are usually found in cold climates.

pine fir cycas cone of pine

Angiosperms

Plants such as the coconut, mango, rose, maize, pea and gram are called
angiosperms. They have the flower with closed seed. Thus, flowering plants with
closed seeds are called angiosperms. Some angiosperms have one cotyledon
(seed leaf) while others have two cotyledons in their seed. So, on the basis of the
number of cotyledon, angiosperms are also classified into two groups:
monocotyledonous plants and dicotyledonous plants.

Oasis School Science and Technology -6 79

Monocotyledonous plants

Plants that have only one cotyledon in their seed are known as monocotyledonous
plants. For example, maize, paddy, wheat, bamboo, garlic, ginger, etc. They have
long and narrow leaves with parallel veins in them. Most of them have fibrous
roots.

paddy plants wheat garlic maize plants bamboo

Dicotyledonous plants

Plants having two cotyledons in their seed are called dicotyledonous plants. For
example, pea, gram, mustard, apple, mango, rose, etc. Leaves of such plants are
flat and short, with their branched veins joined in a central vein.

mango apple mustard pea gram

Activity

Visit a garden or field having both monocotyledonous and dicotyledonous
plants. Observe the outer features of these plants based on the following
table. Discuss what you found with your teacher.

Features Any Monocot Plant Any Dicot Plant
Leaves Long and narrow Short and flat
Root
Stem
Veins in leaves

80 Oasis School Science and Technology -6

Exercise

1. Write True for the correct and False for the incorrect statements.
a. Plants with a single seed leaf in them are called monocots.

b. Pines bear cones instead of flowers.
c. Algae and fungi are examples of thallophytes.
d. Fern is the simplest form of non-flowering plant.
e. Wheat is an example of a dicotyledonous plant.
2. Fill in the blanks with appropriate words.
a. Angiosperms have their ………….. covered in fruit.
b. …………….. is an example of algae.
c. Non-green plants are also called ……………
d. Fern is found in …………… and …………….. places.
e. ……………… plants have long and narrow leaves with parallel veins.
3. Match the following:

Column A Column B

Thallophyta Cycas

Bryophyta Fern

Pteridophyta Bamboo

Angiosperms Algae, fungi and bryophytes

Gymnosperms Mosses

4. Select the best alternative.
a. It is an example of dicots.

i. pea ii. ginger iii. grass iv. onion

b. It bears cones.

i. fern ii. banana iii. pine iv. bamboo

c. It is a green aquatic plant without distinct plant parts.

i. yeast ii. spirogyra iii. pea iv. fern

Oasis School Science and Technology -6 81

c. It depends on dead or decayed organic matter for its food.

i. mushroom ii. lycopodium iii. bamboo iv. pine

d. It is an example of monocotyledonous plants

i. bamboo ii. garlic iii. barley iv. all

5. Write your answer to the following questions in a word each.
a. What is another name for non-flowering plants?

b. What is another name of phanerogams?

c. Monocotyledonous and dicotyledonous plant divisions.

d. Highly developed non-flowering plants fall in this group.

6. Write any two differences between the following:
a. Angiosperm and gymnosperm

b. Cryptogams and phanerogams

c. Algae and fungi

7. Give reasons.
a. Fern falls in cryptogams.

b. Maize is known as monocotyledonous plant.

c. Mustard is a dicotyledonous plant.

8. Name the following plants and list one important feature of each.



9. Answer the following questions.

a. Define the following terms with two examples of each.

i Cryptogams ii. Phanerogams iii Thallophytes

iv Bryophytes v. Pteridophyts vi Angiosperms

vii Gymnosperms

b. List two contrasting features each of monocotyledonous and
dicotyledonous plants with examples.

c. Where can you find algae and fungi around your surrounding?

82 Oasis School Science and Technology -6

4 BEiondviivreornsmityenatndUnit Estimated Teaching Periods:

Theory Practical
11 4

4.1 Environment and Its Balance 4.2 Ecosystem

The earth is a living planet. It is home to all living organisms. There are countless
plants and animals on the earth. They differ in their structure, size, color, habit
and habitat. Some organisms are very small and others are very big; some are
aquatic and others are terrestrial. Thus, the variety and variability of living things,
their communities and habitats make up the biodiversity.

Fig.: biodiversity

There are different kinds of plants and animals in our surroundings. They are
called living things. Similarly, in our neighborhood, there are also different non-
living things such as the rock, soil, water, sunlight, land and air. Environment
refers to all these living and non-living things present in the surrounding areas.
Thus, the environment is a combination of all living, non-living, natural, artificial,
social and cultural things found in our surroundings.

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4.1 Environment and Its Balance

Topics in Their Order according to CDC Curriculum

1. Introduction to environment and its balance
2. Environmental conservation
3. Environment-friendly behaviour (3R)

Learning outcomes

At the end of this unit, students will be able to:
1. Explore their environment.
2. Show how to adopt environment-friendly behaviours.

Key terms of the unit

Natural components: Natural components are the things which are formed by
nature.
Environment conservation: The process of using natural resources wisely
without disturbing their condition and balance is called environment
conservation.
Eco-friendly behavior: Those human activities that do not harm or damage the
environment are called environment friendly or eco-friendly behavior.
Reduce: Reduce means to decrease the use of products that degrade the
environment.
Reuse: Reuse means using the same things again and again for similar or
different purposes.
Recycle: Recycle is a process of making new goods from old ones.

In our environment, living and non-living things constantly interact with one
another. Non-living things provide essential conditions for the survival of living
beings. Animals and plants need air, water, sunlight and soil to survive. Life is
not possible without non-living things. There is a close interaction between living
and non-living things. An imbalance between these things creates a threat to life
on the earth. So, natural components must be maintained in their fresh and
healthy conditions for the continuity of life on the earth.

84 Oasis School Science and Technology -6

Natural components of environment

Have you heard of such phrases:
artificial environment, social
environment, home environment
and school environment? What
concerns us here in this class is the
natural environment, which is made
up of the natural components
surrounding us. The air, water, land,
sunlight, plants and animals are the
most important natural components
of the environment. Natural
components are the gift of nature.
Non-living (abiotic) natural
components and their proper balance
in the nature are required for the
existence and development of living
organisms, the biotic components,
on the earth. Now, let us get down to
exploring these components of our
environment.

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Air

Air is an important non-living natural component of the environment. It is very
light and is blowing everywhere. The atmosphere contains a mixture of various
gases such as oxygen, hydrogen, nitrogen and carbon dioxide. Air is important
for all animals and plants. Animals take oxygen and breathe out carbon dioxide.
Plants use carbon dioxide for photosynthesis and exhale oxygen. Air is necessary
for burning fire. It is also necessary to maintain the earth’s temperature. Therefore,
without air, life on the earth will be impossible.

Water

After air, water is another component essential for living organisms to survive on
the earth. Water covers two-thirds of the earth's surface. But hardly 3% of water
is fresh and suitable for drinking. Oceans, seas, rivers, ponds, mountains, rains,
lakes, etc. are the sources of water. The water present in seas and oceans is salty
and not appropriate for drinking. Terrestrial animals, along with human beings,
and plants require fresh water to survive. We need water for many purposes:
drinking, cleaning, cooking, irrigation, hydropower, etc. The natural conditions
of water and its sources must be maintained for our life to go on.

86 Oasis School Science and Technology -6

Land

Land is made up of rocks and soil.
It has different minerals. Terrestrial
plants grow on land and get
nutrients from it. Terrestrial
animals live on land. They depend
on plants directly or indirectly.
Human activities are based on land.
There is a constant interaction
between land and organisms. When
living organisms die, their bodies change into compost and release minerals in
the soil. Plants get these minerals from the soil. This cycle of interaction goes on
repeating. In the same way, rocks disintegrate and form soil and soil is lumped
together to form rocks. This process also goes on forever. This way, the land
plays an important role in the natural environment.

Sunlight

Sunlight is one of the most important
components of the natural
environment. The sun supplies light
and heat. Organisms need light and
heat for their survival. In the absence
of sunlight, we cannot imagine life on
the earth. The heat of the sun helps
the air flow around. Plants prepare
their food in the presence of sunlight.
Water cycles depend on sunlight. When water of the seas, oceans and other
sources is heated, it changes into vapour in the cloud and falls back on the land
in the form of rain. This way, sunlight plays a vital role to create and maintain the
living environment on the earth.

Plants

Plants are the living components
of the natural environment. They
grow on land and prepare their
food on their own. There are a
variety of plants on the earth.
Plants play an important role for
the survival of animals. All
animals directly or indirectly get

Oasis School Science and Technology -6 87

their food from plants. Plants provide habitat to wild animals. This way plants
help biodiversity to exist and continue on the earth.

Animals

Like plants, animals are also
important living components of
the natural environment. Animals,
big and small, need food. On the
basis of food habits, animals are
placed in three groups: herbivores,
carnivores and omnivores:
Herbivores eat plants, carnivores
eat herbivores and omnivores eat
both plants and animals. When
animals die, their bodies
decompose and change into
minerals in the soil. Plants get
minerals from the soil. This cycle of interaction between animals and plants goes
on forever. This interactive relationship helps the natural environment and
biodiversity maintain their balance.

Environmental conservation and friendly habits

The earth is home to all living beings. Organisms live because the natural
environment makes their life possible. To support life, the components of natural
environment, the air, water, land, sunlight, plants, and animals, must be in their
proper conditions. Environmental conservation is important to keep these
natural conditions intact. The process of using natural resources wisely without
disturbing their conditions and balance is called environmental conservation.

deforestation smoke from industries unplanned settlement

Humans use natural resources for their wellbeing. For many years, their
population has been increasing. So, under the population pressure, several forests

88 Oasis School Science and Technology -6

and open areas have turned into cities. Other components, such as water, water
sources and minerals are being excessively used for the benefit of human beings.
This has increased air, water and land pollution. As a result, the natural
environment has changed radically.

Human activities are mainly responsible for the environmental degradation.
Many plants and animals have disappeared due to the imbalance in the
environment. Even aquatic animals are at a great risk due to water pollution. So,
human beings must be conscious while using the components of environment in
their favor. We should develop environment-friendly habits for the sustainability
of all living beings on the earth. Only a wise use of resources will help us protect
the environment for life on the earth to go on.

Activity

What will happen to your community if all trees in its surroundings are cut
down by a timber company? Discuss this issue in a group and prepare a report.

Environment-friendly behaviors

Development activities depend on

the natural components of the

environment. They may be causing

an imbalance in the components of

the environment. So while carrying

out development activities, we must

use resources such as forests, land,

minerals and water wisely. Such

thoughful activities are called

environment-friendly activities.

Thus, human activities that do no

harm or damage to the environment

are called environment-friendly or

eco-friendly behaviors.

Human beings are using natural
resources randomly and selfishly. Urbanisation and industrialisation have
increased air, water and land pollution. Many wild creatures have disappeared

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due to deforestation. Due to pollution and global warming, life on the earth is at
risk. These things are happening because of human activities that are selfish and
foolish. So, we must be serious about this issue. We should use resources in an
appropriate and careful manner. The following 3R methods, which are
environment-friendly behaviors, are keys to sustaining our resources and
environment. They are Reduce, Reuse and Recycle.

Reduce

Human beings are using natural resources excessively.
Land, forest, water, mineral, etc. are being exploited in
large quantities. People are choosing comfort at the cost of
environment. They are using the means of transportation
for their comfort. Excessive use of fossil fuels has increased
air pollution. Land has been polluted due to chemical
insecticides, pesticides, fertilizers, etc. Not only land, air
and water resources are getting equally polluted, too.

Reduce is an idea to decrease the use of products that degrade the environment.
The practice of less use can help us control pollution. We must try to use less of
everything. We should try to use less fossil fuel, which helps us control air
pollution. If possible, we should walk, rather than using vehicles. We should not
use poly bags. We should use less quantity of chemical fertilizer in the soil. If all
humans try to reduce wastage from their level, their efforts will ultimately go to
protect the environment.

Reuse

We use natural resources to carry out our daily activities.
Excessive use of natural resources to produce substances
again and again harms the environment. So, we should
try to reduce the production of goods that deplete our
resources. To do so, we should try to use the same thing
again and again as far as possible for the same purpose
or the other. It helps us reduce the wastage, too. For
example, using the same poly bag again and again
reduces the plastic heaps. There are so many things which can be used again and
again. This is an environment-friendly step. Thus, reuse means using the same
thing again and again for similar or even different purposes.

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Recycle

Recycle means making new goods from the old ones. This
helps us reduce the heaps of wastage in the environment.
Recycling of waste reduces the excessive use of natural
resources. Not only this, it also helps us protect natural
resources from exploitation for new goods. Reducing the
consumption of natural resources ultimately helps the
efforts at environmental conservation. Some example items
for recycling are plastic bags, metals, glass and old garments.

Exercise

1. Fill in the blanks with appropriate words.
a. Using a plastic bottle again and again is an example of ……………..
b. …………………. is the most important substance for living beings.
c. About 3% of total water of the earth surface is …………………. water.
d. Environment-friendly behaviour is now replaced by …………………..
behaviour.
e. ……………… means to decrease the amount of substance we use.

2. Match the following:

Natural environment Mixture of gases

Social environment Minerals

Land School

Water Plants and animals

Air Fresh and salty

3. Write True for the correct and False for the incorrect statements.
a. Biodiversity refers to the variation among animals and their habitats.

b. Conservation of environment stops the development of mankind.

c. Recycle is an idea of changing the materials into its original or similar
other forms.

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d. Schools, temples, hospitals, roads etc. are the components of natural
environment.

e. Our social and cultural components are also parts of our environment.

4. Write your answer to the following questions in a word each..
a. What is the term for using the same thing again and again?

b. Give an example of social environment.

c. What is an example component of a natural environment?

d. What are the resources given by the nature called?

e. What is the term for the combination of biotic and abiotic things?

5. Write any two differences between the following:
a. Reuse and recycle

b. Reduce and reuse

c. Artificial environment and natural environment

6. Give reasons:
a. All water found on the earth cannot be used for drinking.

b. Sun is the ultimate source of energy.

c. Give an example of each of the following.

a. Reuse b. Reduce c. Recycle

d. Natural environment e. Artificial environment

7. Define the following terms:

a. Biodiversity b. Environment c. Natural resources

d. Environmental conservation e. Environment-friendly behavior

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