Page No 32:
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?
(a) Wool is obtained from the hairy fibres (hair) of the sheep.
(b) White fleece of the lamb refers to the white coloured hair of the lamb.
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
(iii) both a and b
Which of the following does not yield wool?
(i) Yak (ii) Camel (iii) Goat (iv) Woolly dog
What is meant by the following terms?
(i) Rearing (ii) Shearing (iii) Sericulture
(i) Rearing: Rearing means helping someone to grow up.
(ii) Shearing: It is the process of removal of fleece along with a thin layer of skin from the body of sheep.
(ii) Sericulture: Sericulture refers to the rearing of silkworms to obtain silk.
Given below is a sequence of steps in the processing of wool. Which are the missing steps? Add them.
Shearing, __________, sorting, __________, __________, __________
Shearing, __scouring__, sorting, __picking of burrs__, __dying of fibres__, making of yarn__
Make sketches of the two stages in the life history of the silk moth which are directly related to the production of silk.
The two stages in the life history of silk moth directly related to silk production are
Out of the following, which are the two terms related to silk production?
Sericulture, floriculture, moriculture, apiculture and silviculture
Hints: (i) Silk production involves cultivation of mulberry leaves and rearing silkworms.
(ii) Scientific name of mulberry is Morus alba.
Sericulture and moriculture
Match the words of Column I with those given in Column II:
|(i)||Scouring||(a)||Yields silk fibres|
|(ii)||Mulberry leaves||(b)||Wool yielding animal|
|(iii)||Yak||(c)||Food of silk worm|
|(e)||Cleaning sheared skin|
|(i)||Scouring||(e)||Cleaning sheared skin|
|(ii)||Mulberry leaves||(c)||Food of silk worm|
|(iii)||Yak||(b)||Wool yielding animal|
|(iv)||Cocoon||(a)||Yields silk fibres|
Page No 33:
Given below is a crossword puzzle based on this lesson. Use hints to fill in the blank spaces with letters that complete the words.
(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
NCERT Solutions for Class 7 Science Chapters
- Chapter 1 – Nutrition in Plants
- Chapter 2 – Nutrition in Animals
- Chapter 3 – Fibre to Fabric
- Chapter 4 – Heat
- Chapter 5 – Acids, Bases and Salts
- Chapter 6 – Physical and Chemical Changes
- Chapter 7 – Weather, Climate and Adaptations of Animals to Climate
- Chapter 8 – Winds, Storms and Cyclones
- Chapter 9 – Soil
- Chapter 10 – Respiration in Organisms
- Chapter 11 – Transportation in Animals and Plants
- Chapter 12 – Reproduction in Plants
- Chapter 13 – Motion and Time
- Chapter 14 – Electric Current and its Effects
- Chapter 15 – Light
- Chapter 16 – Water: A Precious Resource
- Chapter 17 – Forests: Our Lifeline
- Chapter 18 – Wastewater Story
NCERT Solutions for Class 7: