Here are solutions to NCERT (QUESTIONS AND ANSWERS) FOR CLASS 7 SCIENCE CHAPTER 3 Fibre to Fabric
Q1. You must be familiar with the following nursery rhymes;
- ‘Baa baa black sheep, have you any wool.’
- ‘Mary had a little lamb, whose fleece was white as snow.’
Answer the following
- Which parts of the black sheep have wool?
Ans. The hair of the black sheep has wool.
- What is meant by the white fleece of the lamb?
Ans. The white fleece of the lamb means its white fur.
Q2. The silkworm is (a) a caterpillar, and (b) a larva.
Choose the correct option.
- A
- B
- Both a and b
- Neither a nor b.
Ans. 3
Q3. Which of the following does not yield wool?
- Yak
- Camel
- Goat
- Woolly dog
Ans. 4
Q4. What is meant by the following terms?
- Rearing
- Shearing
- Sericulture
Ans. (i) Raising domestic animals like sheep, goats, yak, cows, and buffaloes for commercial purposes such as milk and fur is known as rearing.
(ii) Shearing is a process of removal of animal hair by using machines.
(III) Rearing of silkworms to get silk is known as Sericulture.
Q5. Given below is a sequence of steps in the processing of wool. Which are the missing steps?
Add them.
Shearing, Scouring, sorting, cleaning of burrs, dyeing, rolling.
Q7. Out of the following, which are the two terms related to silk production?
Sericulture, floriculture, moriculture, apiculture and silviculture.
Hints
- Silk production involves the cultivation of mulberry leaves and rearing silkworms.
- The scientific name of mulberry is Morus alba
Ans. Sericulture and moriculture.
Q8. Match the following
- Scouring = cleaning sheared skin
- Mulberry = food of silkworm
- Yak = wool-yielding animal
- Cocoon = yields silk fibers
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
- Thorough washing
- Animal fiber
- Long thread-like structure
Across
- Keeps warm
- Its leaves are eaten by silkworms
- Hatches from egg of moth