I. Multiple Choice Questions (MCQs).
Q.1. Cotton is a natural polymer made of pure
c) both (a) and (b)
Answer b) cellulose
Q.2. Which of the following fibre is called golden fibre?
a) Jute fibre
b) Cotton fibre
c) Flax fibre
d) none of these
Answer a) Jute fibre
Q.3. The process of removal of fleece from sheep is called
d) none of these
Answer c) shearing
Q.4. The rearing of silkworm for the production of silk is called
d) none of these
Answer: (b) sericulture
Q.5. The second largest producer of silk is
d) none of these
Answer a) India
II. Fill in the blanks by selecting appropriate words from the given list :
List : Cold, Flax, Khadi, spinning, bales
Q.1. In India, _______________ is made from cotton fibres.
Q.2. The ginned cotton is pressed into bundles called _______________.
Q.3. _______________ fibre is obtained from the stem of the flax plant.
Q.4. The process of making yarn from fibres is called _______________.
Q.5. Woollen clothes are good for wearing during the ______________ weather.
Answer. 1- Khadi, 2- bales 3- Flax, 4- spinning 5- Cold
III. Match the items of Column A with those of Column B.
Ans- 1-( c) , 2-(e) , 3-(b) , 4-(a) , 5-(d)
IV. Write ‘T’ for the true and ‘F’ for the false statements.
Q.1. The fibres are twisted together to make yarn.
Q.2. Woollen fibres are obtained from the fleece of sheep or goat.
Q.3. Silk fibre is drawn from the mulberry leaves.
Q.4. In the retting process, the stems of the jute plants are tied into bundles and soaked in pond water for a few days.
Q.5. The rearing of silkworms for the production of silkworm is called apiculture.
Answer 1- F, 2-T, 3-F, 4-T, 5-F
V. Very Short Answer Questions.
Q.1. Name three fibres obtained from plants.
Answer: Cotton, jute and flax.
Q.2. Name two fibres obtained from animals.
Answer: Wool and silk.
Q.3. Define sericulture.
Answer: The rearing of silkworms for the production of silk is called sericulture.
VI. Short Answer Questions.
Q.1. What do you mean by silk-cotton plant? What are its uses?
Answer: Silk cotton plant is a type of native cotton tree with large red flowers. Its fibres are used in making floss, life-preservers, stuffing materials and insulation.
Q.2. How is quality of wool decided? Name a good quality of wool.
Answer: The quality of wool depends on the breed of sheep. The quality is decided on the basis of colour, thickness, length, shine and strength of the fibre. Pashmina, is a good quality wool.
Q.3. How are cotton fibres obtained from cotton plants? Discuss main properties of cotton.
Answer: Cotton plants produces a small, green fruit of the size of a lemon, called cotton boll. The cotton boll contains soft white fibres which grow around the seed. When the fruit matures, it turns brown in colour. The brown boll bursts open and the white fibres are exposed. When these fibres dry in the sun and become fluffy, they are picked by hand.
Main properties of cotton:
• It is a traditional cool summer fabric, though it is comfortable during the wet climate also.
• It is durable and absorbs dyes easily.
• Cotton fibres can be twisted to make strong yarns during spinning.
• It is soft and comfortable to the skin.
• It is a bad conductor of heat and electricity.
Q.4. Where are jute cultivated in India? Write its uses.
Answer: Jute is mainly cultivated in West Bengal, Bihar and Assam.
Used of Jute
• To make cloth, mainly for wrapping bales of raw cotton.
• To make sacks, ropes, carpets, curtains and cushions.
• To make coarse cloth.
• Its fibres are woven into hessian cloth and backing for linoleum and carpets.
• It is used to make sugar and coffee baggings.
Q.5. Why it is necessary to spin the fibres so as to make yarn?
Answer: It is necessary to spin the fibre because when fibers are spun, they form a coherent whole. It keeps them together.
VII. Long Answer Questions.
Q.1. How are woollen fibres obtained from the hair of sheep?
Answer: Wool fibre is obtained from the hair of sheep. The hair is removed from the sheep with the help of a special clipper or a large razor. This process of removal of wool from sheep is called shearing. Shearing is also carried out with the help of a shearing machine.
Q.2. How are silk fibres obtained from the cocoon of silkworm? Why are these fabrics valuable?
Answer: Silk is obtained from the cocoon of silkworm. There are four stages in the life cycle of a silkworm— egg, larva, pupa and adult. The silkworm or larva feeds on mulberry leaves and spins a cocoon around itself. Each silkworm produces a single continuous thread of raw silk
300- 900 metres long. The cocoons are boiled in water to kill the silkworms and it is unwound to get the silk fibre.
These are very expensive due to their production cost.
Q.3. Discuss various processes involved in making fabrics from fibres.
Answer: At maturity, the cotton bolls burst open and the white cotton fibre can be seen.
1. Ginning: The cotton picked up from the plants has seeds in it.
2. Spinning: The process of making yarn from fibre is called spinning.
3. Weaving: The process of arranging two sets of yarn together to make a fabric is called weaving
Q.4. Write differences between natural and synthetic fibres.
Answer: Difference between Natural and Synthetic fibres
Q.5. Explain the process of making yarn from cotton fibres. Give two uses of cotton.
Answer: The process of making yarn from fibres is called spinning. In this process the cotton fibres are pulled to make them straight and then twisted. This makes the yarn stronger. Spinning is done with the help of simple devices like takli or charkha. On a large scale, spinning is done with the help of spinning machines.