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Chapter Review:

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• The animal fibre are Wool and silk. 
• Wool obtains from animals like sheep, goat, yak and some other animals.
• The process of selecting parents for obtaining special characters in their offspring,such a soft under hair in the sheep,is termed selective’.
• The sheep has two types of fibres.  (i)  The coarse beard hair  (ii)  The fine soft. 
• The rearing of silkworms for obtaining silk is called sericulture.
• The caterpillar completely covers itself by silk fibers and turns into pupa. This covering is known as cocoon.
• The female silk moth lays eggs, from which hatch larvae which are called caterpillars or silkworms.
• When the caterpillar is ready to enter the next stage of its life history called pupa.
• The caterpillar completely covers itself by silk fibres. This covering is known as cocoon.
• The silk yarn (thread) is obtained from the cocoon of the silk moth.
• The most common silk moth is the mulberry silk moth.
• The process of taking out threads from the cocoon for use as silk
  is called reeling the silk.
• Silk fibres are made of a protein.

Exercise:

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Q1. You must be familiar with the following nursery rhymes:

(i) ‘Baa baa black sheep, have you any wool.’

(ii) ‘Mary had a little lamb, whose fleece was white as snow.’

Answer the following:

(a) Which parts of the black sheep have wool?

(b) What is meant by the white fleece of the lamb?

Answer:

[a] Mainly the abdomen and back of the sheep have wool.

[b]White fleece refers to the white hair of lamb that is used to make wool.

Q2. The silkworm is

(a) a caterpillar

(b) a larva.

Choose the correct option.

(i) a (ii) b (iii) both a and b (iv) neither a nor b.

Answer:

[a] Caterpillar.

Q3. Which of the following does not yield  wool .

(i) Yak (ii) Camel (iii)Goat (iv)wooly dog

Answer:

(iv)wollydog

Q4. What is meant by the following terms?

(i) rearing (ii) Shearing (iii) Sericulture 

Answer:

(i) Rearing: The bringing up and looking after the livestoks and other animals for our commercials benefit is known as rearing.

(ii) Shearing: To obtain wool, the fleece of the sheep along with a thin layer of skin is removed from its body. This process is called shearing.

(iii)sericulture: The rearing of silkworms for obtaining silk is called shearing.

Q5. Given below is a sequence of steps in the processing of wool. Which are the missing steps?

Add them. Shearing, __________, sorting, __________, __________.

Answer:

Scouring,dying,rolling into yarn.

Q6. Make sketches of the two stages in the life history of silk moth which are directly related to the production of silk.

Answer:

Q7. Out of the following, which are the two terms related to silk production?

Sericulture, floriculture, moriculture, apiculture and silviculture.

Hints: (i) Hints: Silk production involves cultivation of mulberry leaves and rearing silkworms. (ii) Scientific name of mulberry is Morus alba.

Answer:

Sericulture and moriculture.

Q8. Match the words of Column I with those given in Column II: Column I                                 Column II

1. Scouring                           (a) Yields silk fibres

2. Mulberry leaves                    (b) Wool yielding animal

3. Yak                                (c) Food of silk worm

4. Cocoon                            (d) Reeling

                                      (e) Cleaning sheared skin

Answer:

Column 1	Column 2
1.Scouring	(e) cleaning sheared skin
2.Mulberry leaves	(c) Food of silkworm
3.Yak	(b) Wool yielding animal
4.Cocoon	(a) Yeilds silk fibres

Q9. Given below is a crossword puzzle based on this lesson.

Use hints to fill in the blank spaces with letters that complete the words.

Down                                  Across

(D) 1 : Thorough washing    (A) 1 : Keeps warm

    2 : Animal fibre              2 : Its leaves are eaten by silkworms

    3 : Long thread like structure 3 : Hatches from egg of moth

 

Additional Short Answered Questions: 

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Ques1: Name the animal fibres.
Ans: Wool and silk. 

Ques2: Where does wool obtain from?
Ans: Wool obtains from animals like sheep, goat, yak and some other animals.

Ques3: What is sericulture?
Ans: The rearing of silkworms for obtaining silk ios called sericulture.

Ques4: What is cocoon?
Ans: The caterpillar completely covers itself by silk fibers and turns into pupa. This covering is known as cocoon.

Ques5: Define term selective breeding. 
Ans: The process of selecting parents for obtaining special characters in their offspring, such a soft under hair in the sheep, is ‘termed selective’.

Ques6: What types of wool fibres are mostly found from sheep that form its fleece?
Ans: The sheep has two types of fibres.
(i) The coarse beard hair.
(ii) The fine soft. 

Ques7: What occupational hazard may be the workers in wool industry?
Ans: They may get infected by a bacterium, anthrax. Which causes a fatal blood disease called sorter’s disease.

Ques8: Where does Pashmina shawls make?
Ans: Jammu and Kashmir. 

Ques9: By which animal is Angora wool obtain?
Ans: Angora goat of Jammu and Kashmir.

Long Answered Questions: 

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Ques1: Name the animals those yield wool?
Ans: (i) Angora goat

(ii) Goat

(iii) Sheep

(iv) Camel

(v) yak

(vi) Llama

(vii) Alpaca 

Ques8: Write the steps of obtaining wool. 
Ans: There are six steps of obtaining wool. 

(i) Shearing: The fleece of the sheep along with a thin layer of skin is removed from its body. This process is called shearing. In this process the hairs are shaved off. The hair provide woolen fibres.

(ii) Scouring : The sheared skin with hair thoroughly washed in tanks to remove grease, dust and dirt. This is called scouring.

(iii) Sorting: The hairy skin is sent to a factory where hair of different textures are separated. This ia called sorting.

(iv) Cleaning of Burrs: The small fluffy fibres, called burrs, are picked out from the hair. The fibres are scoured again and dried. This is the wool ready to be drawn into fibres.

(v) Dyeing : The dyeing in various colours. as the natural fleece of sheep and goats is black, brown or white.

(vi) Rolling into Yarn : The fibres are straightened, combed and rolled into yarn. The longer fibres are made into wool for sweaters and the shorter fibres are spun and woven into woollen cloth.

Ques3: write the life history of the silk moth.
Ans: The female silk moth lays eggs, from which hatch larvae which are called caterpillars or silkworm. They grow into pupa. It first weaves a net to hold itself is known as cocoon. Then they swing and move during these movement they secrete fibre made of a protein which hardens on exposure to air and becomes silk fibre. 

Ques4: Make sketches of the life history of the silk moth. 
Ans: