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CONTENT

1. Preface

2. Acknowledgement

3. Teacher Student's Support Material (TSSM) 1

i) Introduction

Activity 1 1

ii) Classication of Fibres

iii) Sources of Fibres

a) Plant Fibres

Cotton 3

Worksheet 1 5

Linen 6

Worksheet 2 8

Jute 9

Worksheet 3 11

b) Animal Fibres 12

Wool

Activity 2 16

Worksheet 4 17

Worksheet 5 19

Silk 20

Activity 3 22

2. Post Content Worksheets 25

3. Glossary 27

4. References


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PREFACEThe Curriculum initiated by Central Board of Secondary Education -International (CBSE-i) is a

progressive step in making the educational content and methodology more sensitive and responsive

to global needs. It signies the emergence of a fresh thought process in imparting a curriculum

which would restore the independence of the learner to pursue the learning process in harmonywith the existing personal, social and cultural ethos.

The Central Board of Secondary Education has been providing support to the academic needs of

the learners worldwide. It has about 11500 schools afliated to it and over 158 schools situated in

more than 23 countries. The Board has always been conscious of the varying needs of the learners

and has been working towards contextualizing certain elements of the learning process to the

physical, geographical, social and cultural environment in which they are engaged. The CBSE-i

has been visualized and developed with these requirements in view.

The nucleus of the entire process of constructing the curricular structure is the learner. The objective

of the curriculum is to nurture the independence of the learner, given the fact that every learner isunique. The learner has to understand, appreciate, protect and build on knowledge, values, beliefs

and traditional wisdom. Teachers need to facilitate the leaner to make the necessary modications,

improvisations and additions wherever and whenever necessary.

The recent scientic and technological advances have thrown open the gateways of knowledge

at an astonishing pace. The speed and methods of assimilating knowledge have put forth many

challenges to the educators, forcing them to rethink their approaches for knowledge processing by

their learners. In this context, it has become imperative for them to incorporate those skills which

will enable the young learners to become 'life long learners'. The ability to stay current, to upgrade

skills with emerging technologies, to understand the nuances involved in change management and

the relevant life skills have to be a part of the learning domains of the global learners. The CBSE-icurriculum has taken cognizance of these requirements.

The CBSE-i aims to carry forward the basic strength of the Indian system of education while

promoting critical and creative thinking skills, effective communication skills, interpersonal and

collaborative skills along with information and media skills. There is an inbuilt exibility in the

curriculum, as it provides a foundation and an extension curriculum, in all subject areas to cater to

the different pace of learners.

The CBSE introduced the CBSE-i curriculum in schools afliated to CBSE at the international

level in 2010 at primary and secondary level in classes I and IX and subsequently in the session

2011-12 initiated the

curriculum at Class II, VI and class X. The current session will take the curriculum forward to

classes III, VII and XI.

An important feature of the Senior Secondary Curriculum is its emphasis on the specialisation

in different elds of study and preparing a student for higher professional life and career at the

work place. The CBSE-i, keeping in mind, the demands of the present Global opportunities and


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challenges, is offering the new curriculum in the subject of English, Physics, Chemistry, Biology,

Geography, Accountancy, Business Studies, Information and Communication Technology, and

Mathematics at two levels, Mathematics-I for the students of pure sciences and Mathematics-II for

the students of Commerce and other subjects.

There are some non-evaluative components in the curriculum which would be commented upon

by the teachers and the school. The objective of this part or the core of the curriculum is to scaffold

the learning experiences and to relate tacit knowledge with formal knowledge. This would

involve trans-disciplinary linkages that would form the core of the learning process. Perspectives,

SEWA (Social Empowerment through Work and Action), Life Skills and Research would be the

constituents of this 'Core'. The Core skills are the most signicant aspects of a learner's holistic

growth and learning curve.

The International Curriculum has been designed keeping in view the foundations of the National

Curricular Framework (NCF 2005) NCERT and the experience gathered by the Board over the

last seven decades in imparting effective learning to millions of learners, many of whom are now

global citizens.

The Board does not interpret this development as an alternative to other curricula existing at the

international level, but as an exercise in providing the much needed Indian leadership for global

education at the school level. The Curriculum envisages pedagogy which would involve building

on learning experiences inside the classroom over a period of time. The Board while addressing

the issues of empowerment and capacity building of teachers believes that all school must budget

for and ensure teachers involved with CBSE-i are continuously updated.

I appreciate the sincere effort put in by Dr. Sadhana Parashar, Director (Training) CBSE, Dr.

Srijata Das, Education Ofcer, CBSE and the team of Ofcers involved in the development and

implementation of this material.

The CBSE-i website enables all stakeholders to participate in this initiative through the discussion

forums provided on the portal. Any further suggestions are welcome.

Vineet Joshi

Chairman, CBSE


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Acknowledgements

Advisory

Shri Vineet Joshi, Chairman, CBSE

Dr. Sadhana Parashar, Director

(Training), CBSE

Conceptual Framework

Shri G. Balasubramanian, Former Director (Acad), CBSE

Ms. Abha Adams, Consultant, Step-by-Step School, Noida

Dr. Sadhana Parashar, Director (Training), CBSE

Ideators VI-VIIIMs Aditi Mishra Ms Preeti Hans Ms. Charu Maini Ms. Malini Sridhar

Ms Guneet Ohri Ms Neelima Sharma Dr. Usha Sharma Ms. Leela Raghavan

Ms. Sudha Ravi Ms. Gayatri Khanna Prof. Chand Kiran Saluja Dr. Rashmi Sethi

Ms. Himani Asija Ms. Urmila Guliani Dr. Meena Dhani Ms. Seema Rawat

Ms. Neerada Suresh

Dr. Rajesh Hassija

Ms. Anuradha Joshi

Mrs. Sonali Sinha

Ms. Vijay Laxmi Raman

Mrs. Avanita Bir

Ms. Suman Nath Bhalla

Prof Om Vikas

Dr. Rajesh Hassija Mrs. Sonali Sinha Mrs. Avanita Bir Prof Om Vikas

Material Developers Groups: Classes VI-VIII

English :

Ms Neha Sharma

Ms Dipinder Kaur

Ms Sarita AhujaMs Gayatri Khanna

Ms Preeti Hans

Ms Rachna Pandit

Ms Renu Anand

Ms Sheena Chhabra

Ms Veena Bhasin

Ms Trishya Mukherjee

Ms Neerada Suresh

Ms Sudha Ravi

Ms Ratna Lal

Ms Ritu Badia Vashisth

MsVijay Laxmi Raman

Core- Research

Ms. Renu Anand

Ms. Gayatri Khanna

Dr. N K Sehgal

Ms. Anita Sharma

Ms. Rashmi Kathuria

Ms. Neha Sharma

Ms. Neeta Rastogi

Ms. Manjushtha Bose

Ms. Varsha Manku

Dr. K L Chopra

Chemistry :

Ms. Poonam Kumar Mendiratta

Ms. Rashmi Sharma

Ms. Kavita KapoorMs. Divya Arora

Physics :

Ms. Vidhu Narayanan

Ms. Mukta Kaushik

Ms. Patarlekha Sarkar

Ms. Neelam Malik

Biology:

Mr. Saroj Kumar

Ms. Rashmi Ramsinghaney

Ms. Prerna Gosain

Ms. Seema KapoorMr. Manish Panwar

Ms. Vikram Yadav

Ms. Monika Chopra

Ms. Jaspreet Kaur

Ms. Preeti Mittal

Ms. Shipra Sarcar

Ms. Leela Raghavan

Mathematics :

Ms. Deepa Gupta

Ms. Gayatri Chowhan

Ms. N VidyaMs. Mamta Goyal

Ms. Chhavi Raheja

Hindi:

Mr. Akshay Kumar Dixit

Ms. Veena Sharma

Ms. Nishi Dhanjal

Ms. Kiran Soni

CORE-SEWA

Ms. Vandna

Ms. Nishtha Bharati

Ms. Seema BhandariMs. Seema Chopra

Ms. Reema Arora

Ms. Neha Sharma

ICT

Mr. Yogesh Kumar

Ms. Nancy Sehgal

Ms. Purvi Srivastava

Ms. Babita Mahajan

Ms. Ritu Arora

Ms. Swati Panhani

Ms. Chanchal Chandna

Geography:

Ms Suparna Sharma

Ms Aditi Babbar

History :

Ms Leeza Dutta

Ms Kalpana Pant

Ms Ruchi Mahajan

Political Science:

Ms Kanu Chopra

Ms Shilpi Anand

Economics :

Ms. Leela Garewal

Ms Anita Yadav

CORE-Perspectives

Ms. Madhuchhanda,RO(Innovation)

Ms. Varsha Seth, Consultant

Ms Neha Sharma

Chief Co-ordinators: Dr. Srijata Das, EO

Co-ordinators

Ms. Sugandh Sharma,

E O

Ms.S. Radha Mahalakshmi,

E. O.

Dr Rashmi Sethi, E O Ms. Madhu Chanda, R O

(Inn)

Mr. Navin Maini, R O

(Tech)

Shri Al Hilal Ahmed, AEO Mr. R P Singh, AEO Ms. Anjali, AEO

Ms. Neelima Sharma,

Consultant (English)

Shri R. P. Sharma, Consultant

(Science)

Mr. Sanjay Sachdeva, S O


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1

TEACHER STUDENT'S SUPPORT MATERIAL (TSSM)

NATURAL FIBRES

We prefer wearing cotton clothes during summers and woolen clothes in winters. Have you

ever wondered how a cotton fabric or a woolen yarn is obtained? How does the cotton we use

to make a wick or ear bud gets converted to a shirt? How does wool we see over a sheeps body

gets converted to the yarn used to knit sweaters? Let us explore and answer these interesting

questions.

Activity 1

Aim: To study that fabrics are made up of bres.Material required: A small piece of cotton or jute or linen fabricanda scissor.

Steps:

1. Cut a small piece of fabric using scissors.

2. Pull few threads/yarns out of them.

3. Press one end of the thread with your thumb and scratch the other with your nails or pin/

needle.

Observation:

You will see loose threads or yarns at the edges. Notice that the cloth is made of a number of

such strands woven together.

You will also observe that yarn splits into thin strands which on further scratching, splits into

still thinner bres.

Conclusion: Fabrics are made of yarns woven together and yarns are made up of bres.

Now the question comes how these strands of bres made into are yarns and how are yarns

made into fabrics? Explore.

FIBRES ------------> YARN ------------> FABRIC

NATURAL FIBRES AND FABRICS


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Natural ibres are substances produced by plants and animals. Cotton, Wool, Juteare some examples of natural ibres. These can be spun into threads or ropes or

can be woven and knitted to form fabrics.

Synthetic bres are man-made bres that are produced articially by processing and chemical

treatment of certain substances. E.g. Rayon is made from cellulose


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3

PLANT FIBRES

A. COTTON

Cotton is the most important of all plant bres used to make clothes. It has special

properties that make it the best choice for people to wear it especially during summerseason.

Properties

Cotton bres have a natural twist that makes them suitable for spinning into a very

strong yarn.

It is a soft and uffy bre.

Water reaches the core of the bre easily and removes the dirt from the cotton garments.

Its crease can easily be removed by ironing.

Due to its ability to absorb moisture cotton fabric is comfortable to wear during

humidity.

They are porous in nature and allow air to penetrate and keep the body cool.

They are eco-friendly as they are biodegradable.

COTTON CULTIVATION AND PROCESSING

It is a warm season crop and needs a moderate rainfall and black soil for best production. The

bres grow in a ball around the seeds of a cotton plant.

Cotton seeds are planted in early spring. Cotton seeds grow steadily

and within a span of two months become bushes. They start bearing

yellow or white owers, which turn pink within a week. At this

moment green pods appear which may contain two or more seeds.

The seeds develop within the pods and are gradually covered with

white brous material which is called cotton. The pods then grow

into spherical structures of the size of walnut, and are commonly

called cotton balls.

After maturing the cotton balls are picked up from the elds eithermanually, using hands or mechanically, using machines. The seeds

are separated from them by combing. This process of separation of

seeds from cotton balls is known as ginning.

The process of making a yarn from bres is called spinning. In

spinning the bres from a mass of cotton wool are drawn out and

twisted. This brings the bres together to form a yarn.

A cotton ball

Ginning machine


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You can try spinning and making a yarn yourself. Take some cotton and start pulling out a few

bres. While pulling, twist them too. You will notice that yarn is formed. Spinning can be done

by a charkha (spinning wheel) or a takli (spindle).

Weavingis interlacing of two sets of yarns at right angles to make a fabric. Weaving is done

on looms. Hand operated looms are called handloomsand the ones which are power operated

are called power looms.


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WORKSHEET 1

1. Why Cotton clothes are considered as bio degradable?

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

2. The fruit of cotton is also called ____________.

3. Name the following:

a) A simple device used for spinning cotton.

_____________________________________________________________________

b) Process of removing seeds from cotton bres.

_____________________________________________________________________

4. Name the process by which seeds are removed from cotton balls.

_____________________________________________________________________

5. When are cotton seeds sown in the soil? And when do they start bearing owers?

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________


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B. Linen

Linen is a textile made from the bres of the axplant. Today linen is usually an expensive

textile. Its individual bre length is longer than cotton and other natural bres.

Many products are made of linen: apron, bags, towels, napkins, bed linen, linen table cloth,chair cover, mens and womens wear.

Properties

Linen fabric feels cool to touch.

It has a smooth texture, and softens with each wash.

Linen fabrics have a high natural lustre; their natural color ranges between shades of

ivory, tan, or grey.

When properly prepared, linen fabric has the ability to absorb and lose water rapidly.

It is a very durable, strong fabric, and one of the few that are stronger when wet than

dry.

Linen Production

Flax is one of the few crops still produced in Western Europe,

with nearly 130,000 acres under cultivation annually.

Climatic conditions in this region are perfect for growing

ax. Flax cannot endure very hot weather; thus in many partsof the world, ax are sown in winter because of heat in early

spring.

The growing cycle is short.

To preserve the full potential of each plant, ax is never mowed

but must be uprooted. Earlier this was an exhausting process

done by hand but today, mechanical grubbers do this tiring work.

Therefore while harvesting; ax is always pulled up, never cut,

to preserve the maximum bre length.

After pulling, the ax is tied in bundles known as sheavesor

beetsand taken to a eld to dry. The bundles are untied and the stems are laid out thinly on

the eld, this process is known as grassing.

Once dried, the seeds are moved through a mechanized process called rippling or by

winnowing.


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A process called retting is employed to loosen the bres from the stalk.

In this process, certain bacteria (micro-organisms) are used to decompose

(or break down) the binding material responsible for keeping the bres

together. The bres are thus loosened from the stalk to separate the loosened

bres from the stalk; the process of Scutching is used. Scutching can be

done either by hand or by machine. It involves scraping down and pulling

away pieces of stalk separating the bres. The bres are then heckled.

On passing through heckling combs, the short bres and impurities are

separated. The long, clean bres are thus separated, ready to be spun. After

spinning, it can be used for weaving into Linen.


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WORKSHEET-2


a) Plant from which linen bres are obtained

_____________________________________________________________________

b) Part of the plant from which bres are obtained

_____________________________________________________________________

c) Process of loosening bres from the stem

_____________________________________________________________________

d) Device by which bres are aligned for spinning

_____________________________________________________________________

e) Stage at which Harvesting is done

_____________________________________________________________________

f) Months of sowing ax plant

2. Arrange the following processes in the sequence in which they are performed to make

linen bres from ax plant:

Scutching, retting, harvesting, dyeing, heckling, and spinning

_____________________________________________________________________

_____________________________________________________________________

3. At what stage of production of linen are micro-organisms used and how?

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________


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C. Jute

Another plant bre about which we will learn is jute. As we take the journey from jute bre to

jute fabric you will nd many similarities between the processing of jute and linen.

Jute is a natural vegetable bre. Jute is obtained from the stem of a plant called Patsun. Since

ancient times, it has been traditionally grown in the eastern part of the Indian subcontinent,

which is the present day West Bengal of India and plains of Bangladesh.

Properties

It is one of the strongest and most durable natural bre.

It is biodegradable.

It has superior heat insulation properties.

It has a high tensile strength and ensures better breathability of fabrics. Therefore, juteis very suitable in agricultural commodity bulk packaging.

After cotton, jute is second most important bre in terms of usage, global consumption,

production, and availability. Because of its natural golden colour and silky shine it is known

as The Golden Fibre.

The best source of jute in the world is the Bengal Delta Plain in the Ganges Delta, most of

which is occupied by Bangladesh.

Conditions for growing Jute

Jute needs a plain alluvial soil and standing water. Jute ourishes best under warm and humidclimate with temperature ranging from 24 to 37 degree centigrade.

Jute can be grown on all kind of soils from clay to sandy, loam but loamy alluvial soil suits it

most.

Jute rope Jute bre is being dehydrated after

retting alongside a road


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Jute Production

Jute crop can be harvested between 100 120 days. After harvesting the jute bundles are kept

in the eld for 2 -3 days to allow leaf shedding.

As in case of linen, bres need to be separated from their stem by retting. After the retting

process, stripping begins. In the stripping process, non-brous matter is scraped off, thus the

bres are obtained.

India, Pakistan, China are the large buyers of local jute while Britain, Spain, Ivory Coast,

Germany and Brazil also import raw jute from Bangladesh.

The primary ber is pressed into a highly compressed bale, similar to other bers like cotton

and wool.

Jute bre is extracted from retted stem of jute plants


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WORKSHEET 3


a) Plant from which jute is obtained

_____________________________________________________________________

b) Part of the plant which yields jute bres

_____________________________________________________________________

c) Soil suitable for cultivation of jute plant

_____________________________________________________________________

d) Process by which non brous material is scraped off

_____________________________________________________________________

2. How is retting done?

____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

3. Why are jute bres called golden bre?

_____________________________________________________________________ _____________________________________________________________________

_____________________________________________________________________

4. Why jute is suitable for bulk packaging?

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________

5. Which season is most suitable for cultivation of jute and why?

_____________________________________________________________________

_____________________________________________________________________

_____________________________________________________________________


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ANIMAL FIBRES

A. WOOL

Wool is majorly obtained from sheep. List ve items

that are made of wool

____________ , ______________ , ______________ ,

______________ , ______________ .

Characteristics of wool

It is crimped (the natural wave of wool bre).

Wool is naturally re resistant.

Wool has the ability to stretch and then return to itsnatural length.

Wool readily absorbs water and can also release it.

Because of the crimp, wool fabrics have greater bulk than

other textiles and retain air, which causes the product to

retain heat.

Wool is a natural bre and renewable resource

Other animals that produce wool

Angora Rabbit Found in Angora, Turkey. Produces ne quality

of white or coloured wool called mohair. Mohair is used in making

carpets, scarves, winter hats, suit, sweaters, coats and socks.

Alpaca Camel Found in Peru and other areas of South America.Alpaca camel wool is very ne and of yarn quality and so it is used

for shawls, stoles and carpets.

Did you know?

Bedouins and Turaeg

use woolen clothes to

keep the heat out.


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Angora goatis a descendant of wild goats from the Angora region

in Asia Minor, near present-day Ankara, Turkey.Called by some the

most efcient ber producers on Earth, angora goats are docile and

personable creatures that contribute a wonderful dimension to our

farm.

From bre to wool

Processing of wool involves the following steps.

a) Shearing of wool

b) Scouring

c) Sorting

d) Gradinge) Dyeing

f) Spinning weaving and knitting

a) SHEARING The process of removing eece from the sheeps body is called

shearing. The person who shears the sheep is called shearer. Shearing is usually

done in spring or non winter months as it is not cold and the sheep can live without

its eece. Shearing is done by hands using clippers or a pair of scissors. Machines

are also used to make shearing easy and fast. The eece has to be removed in a

single piece and therefore requires a skilled person. Shearing does not hurt the sheepas the uppermost layer of the skin is dead and the hair of the sheep continues to grow

just as our hair grows.

Shearing


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b) SCOURING After shearing the eece is washed thoroughly in tanks to remove dust,

dirt and grease. This process is called scouring. Nowadays machines are used for this

purpose.

c) SORTING Scouring is followed by sorting. It is done in factories where hair of

different textures are separated and sorted. The small uffy bres are then picked outfrom the hair. You can also observe them in the form of wool burrs in your woolen

clothes.

d) GRADING In this process the wool is grouped according to its length, colour, texture

and ease of drying.

Grading

Scouring

Sorting of wool


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e) DYEING The colour of natural eece of sheep hair is black, brown and white. So, the

processed bres are dyed in various colors depending on our choice.

e) SPINNING, WEAVING AND KNITTING After dyeing the bres are dried andthen straightened combed and rolled into yarn. The shorter bres are spun and woven

into fabrics of desired shape or size. The larger bres are spun and knitted into woolen

garments.

Some breeds of sheep

Name Wool Country

Afrino Fine wool South Africa, Australia

Altay Carpet wool China

Apennine Medium wool Italy

Barki Long wool Middle east

Aragonesa Medium wool World wide

Awassi Carpet wool World wide

Dyeing

Spinning of wool Knitting of wool Knitting of wool


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Activity 2

Read the labels of different wool items:

A) Identify the places where it is manufactured.

_____________________________________________________________________

_____________________________________________________________________

B) How are these to be maintained?

_____________________________________________________________________

_____________________________________________________________________

C) What properties of the wool do you infer from it?

_____________________________________________________________________

_____________________________________________________________________


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WORKSHEET 4

1. Match the following:

Column I Column II

i. Cloth

ii. Very thin hair like threads from which fabric is made

iii. Twisted bres

iv. Synthetic bre

v. Spinning device

vi. Making yarn from bres

vii. Animal bre

viii. Separation of cotton bres from its seeds

ix. Interlinking two sets of yarn

x. Plant bre

a) Fibres

b) Silk

c) Takli

d) Fabric

e) Weaving

f) Cotton

g) Ginning

h) Nylon

i) Spinning

j) Yarn

2. Correct the following statements and rewrite in space provided.

a) Fibre is a material that is woven from threads.

_____________________________________________________________

b) Wool is obtained only from sheep.

_________________________________________________________________

c) Merino wool is obtained from camels.

_________________________________________________________________

d) Bactrian sheep give the best quality wool.

_________________________________________________________________

e) Cashmere goat gives bre called mohair.

_________________________________________________________________

f) Angora goat gives us mohair bres.

_________________________________________________________________


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3. Find out and write examples of:

a) Animal bres

____________________________________________

b) Camel that gives us wool

___________________________________________

c) Goat that gives us wool

_______________________________________________

d) Countries manufacturing wool garments

_______________________________________________

e) Types of silk

_______________________________________________


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WORKSHEET 5

Q1 Fill in the blanks with appropriate words

a) The _______________ of sheep is spun to make yarn.

b) Wool is a _________________ which we get from sheep.

Q2 Why do you think shearing should be done in summers?

____________________________________________________________________

____________________________________________________________________

Q3 Dene the term scouring and grading.

____________________________________________________________________

____________________________________________________________________

Q4 Write S for man made and N for natural bre.

a) Nylon ________ b) Cotton __________

c) Wool _________ d) Silk _________

Q5 Which of these is not a natural bre?

a) Nylon b) Jute c) Wool d) Cotton


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B. SILK

Silk is the most beautiful of all textile bres. It is also called the queen of textiles. Silk is also

a protein bre obtained from various insects and spiders. The best known type of silk used in

commercial textiles is produced from the cocoons made by larvae of theBombyx morimoth.

Properties of silk

1. Silk has shimmering appearance which comes from the bres triangular prism like

structure which allows silk cloth to reect incoming light at different angles.

2. It is versatile and comfortable to wear.

3. Can be easily dyed into different colors.

4. Silk is a bad conductor of heat and so it is cool to wear in summers and warm in winters

as compared to cotton and linen.

5. It is the strongest natural bre.

6. It burns with smell of hair.

The four commercially known varieties of silk are: mulberry silk, tassur silk, eri silk and muga

silk.

Do you know from where the silk come from?

Silk is obtained from cocoons of silk moth. What are

cocoons?

To understand it we have to study the life cycle of silk

moth.

The lifecycle of silk moth starts when a female silk

moth lays its eggs on the leaves of a mulberry tree.

These eggs then hatch into larvae. What are these larvae

known as ...

Any guesses? The larva is not a worm at all but a

caterpillar.

Larvae eat voraciously and grow fast. During thisstage they shed their skin four times which is called

moulting.

After four to six weeks the larvae achieve their maximum size and stops eating. A fully grown

larva attaches itself to a twig. At this stage it is called Pupa. The pupa starts secreting bres

from the glands in its head. It moves its head in the shape of number 8 and keeps secreting silk

bres until it is completely covered with them. The bres harden when exposed to air and form

Did you know?

Until World War I,

bullet proof vests

were also made from

silk.

The cultivation of

cocoons of silkmoth

to obtain silk

laments is called

sericulture.


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a shell like structure around the pupa. This hard covering is known as cocoon. The further

development of moth starts inside the cocoon. If the adult moth were allowed to emerge from

the cocoon naturally, it would secrete a chemical, which would eat the cocoon and the silk

bre will get damaged. Therefore the silk worms are killed by dipping them in boiling water,

steaming or drying in an oven. The silk bre obtained by cocoon undergo following steps in

the silk producing factories:

Processing of silk

a) Sorting of cocoons: The cocoons are sorted according to the color, size, shape and

textureas these dene the quality of silk.

b) Softening of sericin: Silk laments are bound together by gummy substance called

sericin. After sorting, cocoons are

put through a series of hot and cold

immersions to soften the sericin. This

allows the unwinding of lament as

a continuous thread.

c) Reeling of filament: Reeling

is the process of unwinding the

filaments from the cocoon. As

the silk fibres are very fine, they

are combined together to make a

thread of raw silk. Three to ten


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strands are usually reeled at a time

to produce the desired thickness of

raw silk.

d) Bailing of lament: The reeled silk

is packed in small bundles calledbooks. These books are put into bales

weighing about 60kg. These are then

transported to the silk mills for silk

production.

e) Weaving: Weaving is a method of

fabric production in which two distinct

sets of yarns of threads are interlaced

at right angles to form a fabric or cloth. The other methods are knitting, lace making and

felting. The longitudinal threads are called the warp and the lateral threads are the weft

or lling. (Weft is an old English word meaning that which is woven.) The method inwhich these threads are interwoven affects the characteristics of the cloth.

Cloth is usually woven on a loom, a device that holds the warp threads in place while lling

threads are woven through them.

Silk weaving is similar to the weaving of other types of yarns: warp and weft threads are

intertwined according to a pattern to produce a woven fabric. Sheer, soft fabrics like chiffon

or lightweight crepe de chine; satin, taffeta, twill, damask, and brocades; even velvets are allwoven from silk.

Activity: 3

Aim: To study different stages of life cycle of buttery or moth.

Material required: Any infested vegetable like pea, brinjal or cauliower, one wide mouthed

bottle, muslin cloth.


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Procedure:

1. Take infested vegetable, and collect the green wriggling worm like creature called larva/

caterpillar from it.

2. Place the caterpillar in the bottle along with some small pieces of vegetable from where

you have collected the caterpillar.

3. Cover the mouth of the bottle with muslin cloth.

4. Record you observations in a notebook.

Observation:

You will observe that after few days caterpillar will transform into a dark brown stationary

structure called pupa or cocoon.

After another few days adult moth will emerge out from the cocoon

Uses of silk

1. In the manufacture of clothes, dress materials, curtains and upholstery.

2. For handicrafts and items like parachutes, bicycle tyres, comforter lling.

3. Through a special manufacturing process, it is made suitable for use as non-absorbable

surgical sutures.

4. Doctors also use it to make prosthetic arteries.

Demonstration

Aim: Identication of Fibres with the help of burning test.

Materials required: Different types of bres, matchbox and a candle

Procedure:- For the burning test:-

1. Take out a yarn from the fabric.

2. Burn one end of the yarn either with a match stick or burning candle.

3. Check the following:

a) How the bre catches re.

b) Type of ame.

c) Smell after burning.

d) Observe and comment upon ash left behind.


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Answers to all these points will help to identify bres

FIBRE INFLAME TYPE OF FLAME SMELL ASH

COTTON AND

RAYON

Catches re easily Continues to burn

with a bright Yellow

ame

Smell of burning

paper

Light feathery ash

SILK AND WOOL Does not catch re

easily

Burns with a yellow

ame. Does not

continue to burn

Smell of burning

hair

Black crushable

bead

NYLON Does not catch re Shrinks away No denite Smell Hard, uncrushable

bead

POLYSTER

ACRYLIC

Easily, melts away Flame. Burns with

sputtering


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POST CONTENT WORKSHEET

1. Choose the correct alternative to answer the following questions:

(i) Which of the fabric is most suitable for summer?

(a) Cotton

(b) Nylon

(c) Silk

(d) TERYLENE

(ii) Which of the following fabrics does not take stains easily?

(a) Cotton

(b) Nylon

(c) Wool

(d) Silk

(iii) Which of the following fabrics is a bad conductor?

(a) Nylon

(b) Wool

(c) Rayon

(d) Cotton

(iv) Which fabric is made of staple bre?

(a) Cotton

(b) Nylon

(c) Polyester

(d) Silk

(v) Which is the strongest bre?

(a) Cotton

(b) Nylon

(c) Rayon

(d) Wool


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(vi) Which fabric has a dull surface?

(a) Nylon

(b) Polyester

(c) Silk

(d) Wool

(vii) Cotton is most desirable fabric for making undergarments because it is:

(a) Absorbent

(b) Dull

(c) Shinning

(d) Strong

2. Name four wool yielding animals.

_______________________________________________________________________

_______________________________________________________________________

3. Name three vegetable bres.

_______________________________________________________________________

_______________________________________________________________________

4. Which complex compounds are animal bres made of?

_______________________________________________________________________

_______________________________________________________________________

5. List few properties of bres.

_______________________________________________________________________

_______________________________________________________________________

6. Why linen is a suitable fabric for making body or wash towels?

_______________________________________________________________________

_______________________________________________________________________

7. What type of soil and climate is required for cultivation of ax?

_______________________________________________________________________

_______________________________________________________________________


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8. Write in brief about retting of ax bres.

______________________________________________________________________

______________________________________________________________________

9. What is Scutching? How is it done?

______________________________________________________________________

______________________________________________________________________

10. Write a short note on spinning of linen bres.

______________________________________________________________________

______________________________________________________________________

11. How does wool bre keep our body warm?

______________________________________________________________________

______________________________________________________________________

12. We wear clothes suited to the weather. Explain the statement giving suitable examples.

______________________________________________________________________

______________________________________________________________________

13. Draw the diagram of life cycle of a silk moth.

14. For obtaining silk bres from cocoons why are cocoon put in boiling water?

______________________________________________________________________

______________________________________________________________________

15. Why are mulberry leaves required during larval stage of silkworm?

______________________________________________________________________

______________________________________________________________________


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16. What is the meaning of books in relation to sericulture?

______________________________________________________________________

______________________________________________________________________

17. Name the natural varieties of silk.

______________________________________________________________________

______________________________________________________________________

18. What is the difference between weaving and knitting?

_______________________________________________________________________

_______________________________________________________________________

19. Your mother goes to buy a woolen shawl from the market. The shopkeeper takes out a small

strand of yarn from the shawl and burns it. It smells of burning plastic. Will it be a good

decision to buy the shawl? Give reason for your answer.

_______________________________________________________________________

_______________________________________________________________________

20. List various stages in the life cycle of silkworm. Can you name some other insects that have

similar life cycle?

_______________________________________________________________________

_______________________________________________________________________

21. Differentiate between;

a) Shearing and scouring

b) Cashmere and angora

_______________________________________________________________________

_______________________________________________________________________

22. Raghu took out a torn shirt. He pulled out few strands called X from his shirt. When he

untwisted them, he found very thin strands called Y. Identify X and Y.

_______________________________________________________________________

_______________________________________________________________________

23. List four types on natural bres and their sources.

_______________________________________________________________________

_______________________________________________________________________


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24. Why is the trade of animal products usually banned in many countries?

_______________________________________________________________________

_______________________________________________________________________

25. Why is sericulture not considered an eco-friendly practice?

_______________________________________________________________________

_______________________________________________________________________


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GlossaryFabric material that is made from bres either natural or articial

Spinning twisting of bres to obtain yarn

Yarn thread obtained after spinning of bres which is ready to be weaved.

Weaving interlacing two sets of yarns to make a fabric.

Sheaves bundles of ax.

Rippling process of removing seeds from dried ax.

Retting microbial decomposition of stem to loosen the bres.

Scutching process of removing straw and other woody material from the ax bres.

Mohair a kind of ne wool obtained from Angora goat.

Shearing process of removal of wool from the skin of an animal with the help of razors.

Scouring removal of dust dirt and grease by using chemicals.

Sericulture commercial rearing of silk to obtain silk.

Resources :

http://www.youtube.com/watch?v=n5i8KRcccDw(link for hand spinning wool)

http://www.authorstream.com/Presentation/Justine-37887-Cotton-as-Education-ppt-powerpoint /(ppt on processing of cotton bres)

galaxysite.weebly.com/uploads/6/4/9/5/6495197/3bretofabric.ppt (ppt on bre to fabric)

http://www.authorstream.com/Presentation/yashrastogi-749387-sericulture-by-yash/ (ppt on

sericulture)

http://www.authorstream.com/Presentation/98Anshul-761112-wool/(ppt on wool)

www.avs.uidaho.edu/avs476/IntroWoolNX.ppt(ppt on wool)

www.jute.org/.../Int.%20Con.%20Feb-2009%20H.%20S.%20Sen.pp(ppt on jute)

http://www.youtube.com/watch?v=yBeHpDqnqMk(video on cotton harvesting and processing)

http://www.youtube.com/watch?v=aSe1gQNl4Ns(spinning of cotton)

http://www.youtube.com/watch?v=RUHMTsfhshY(spinning with the help of takli)


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