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Answer:1 Mark
Reason for shearing being helpful: 1 Mark each
Shearing is generally carried out in summer so that the sheep do not suffer from heat strokes in the summer.
Annual shearing of the sheep is an absolute must for the following reasons:

1. Long fleece can become dirty,drag along the ground, increasing the possibility of flystrike.


2. A bulky fleece decreases the mobility of sheep.


3. Sheep can become susceptible to heat stress during hot weather.


4. Appropriate growth of fleece helps to maintain their body temperature.

:
Explanation: 1 Mark each
1) White fleece means the hairy skin which is white in colour.
2) The hairy skin called fleece has wool in black sheep.

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Reasoning: 2 Marks
We know that air is a poor conductor of heat. It is this attribute of air that keeps these animals warm during winter by not letting the body heat escape. Hence animals grow a natural coat of hair on their bodies during winter.

:
Naming: 1.5 Marks for each question.
The sheep breeds found in India are as follows:
The Nali and Lohi breeds - Rajasthan, Punjab
The Rampur Bushair - Uttar Pradesh, Himachal Pradesh
Bhakharwal - Jammu and Kashmir
Patanwadi, Marwari breed - Gujarat
The following breeds are known for:
The Nali for Carpet wool
Patanwadi wool- Hosiery
Lohi Wool- Making clothes

:
Explanation: 1.5 Marks
Reason: 1.5 Marks
The ethical harvesting of silk by not boiling the cocoons along with the silkworms inside but instead allowing the silkworms to become full grown Bombyx mori moths is called peace silk.
It is named peace silk because in this method the silkworms are allowed to emerge from their cocoons naturally, and die a normaldeath instead of being killed in a cauldron of boiling water. So it is a peaceful method of silk culture.

Answer: Option C. -> Bacteria
:
C
The wool industry is one of the most important means of livelihood for many people. The sorter's job is very risky as they might get infected by a bacterium, anthrax, which causes a fatal blood disease called sorter's disease. Such types of diseases are called occupational hazards.

Answer: Option C. -> Under-hair    
:
C
There are two types of sheep hair – the coarse beard hair which is on the top and the fine soft under-hair, which is close to the skin. This fine-soft under hair provides the fibre to make fine, soft wool.

Answer: Option C. -> silkworm
:
C
Silk is a natural fibre as it is obtained from caterpillars (larva or silkwormsof silk moth of the family, Bombycoidea). Different groups of silk moths are used to produce wild silk, but the silk cultivatedfrom larvae of the mulberry silkworm moth,Bombyx mori, accounts for most commercial production.

Answer: Option D. -> Sorting
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D
Sorting is done after scouring to separate hairs of different textures and types. This is to separate the low and high quality fibres of wool. The figure given below is an image showing sorting of wool.

Answer: Option B. -> sericulture
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B
The rearing of silkworms for obtaining silk is called sericulture.Silkworms are reared under suitable conditions of temperature and humidity to obtain silk threads from their cocoons.