class 7th F Answer the following questions in detail.
1. What are the various steps involved in the process of making wool?
2. Name any five animals that provide wool. Write a line about the wool obtained from them.
3. Explain the process of silk production.
4. What are the occupational hazards of silk industry?
5. What safety and health measures are required in silk industry?
6. What is selective breeding? Mention the advantage of selective breeding of sheep.
G. Think and answer.
1. Why does the secretion produced by the silkworm become hard?
2. Why cotton clothes are preferred in humid weather?
3. Why the cocoon of silkmoth is immersed in hot water?
4. What causes respiratory diseases to the workers of silk industry?
5. Why shearing does not hurt the sheep?
Answers
Answer:
1. The major steps necessary to process wool from the sheep to the fabric are: shearing, cleaning and scouring, grading and sorting, carding, spinning, weaving, and finishing.
2. Names of Animals That Give Wool
Sheep. The most common wool animal is the sheep. ...
Goats. Mohair and cashmere come from goats. ...
Lamas. The Lama genus of animals, all of whom originate in South America, includes llamas, alpacas, vicunas and guanacos. ...
Camels. ...
Rabbits. ...
Musk Oxen.
3. The process of silk production is known as sericulture. ... Extracting raw silk starts by cultivating the silkworms on mulberry leaves. Once the worms start pupating in their cocoons, these are dissolved in boiling water in order for individual long fibres to be extracted and fed into the spinning reel.
4. The rearers in silk industry are engaged in several types of tasks and get exposed to multiple physical, chemical, and biological agents, which make them vulnerable to various health problems that include injuries, musculoskeletal disorders, allergies, eye irritation, and respiratory diseases.
5. deal rearing houses are to be well ventilated with controlled environmental conditions
2. Rearers have to wear sterile gloves while handling dead worms, disinfectant and bed disinfectants.
3. While using formalin and bleaching powder, it is advised to wear face masks and gloves.
4. Proper environmental conditions, good rearing techniques, quality mulberry leaves and races are needed to prevent /control silkworm diseases.
5. Health education and medical supervision is a must at regular intervals t in silk industry.
6. To prevent noise exposure, adequate lubrication of machineries and interposition of sound baffles is necessary.
7. The workers in reeling unit are exposed to noise pollution hence a hearing protection programmed featuring periodic audiograms is desirable.
8. Provision of good sanitation and hygienic condition in reeling unit with frequent replacement of water in reeling basin is necessary.
9. To prevent musculoskeletal problems proper posture is a must.
10. Thus it can be concluded that a industry grow with employees and employers with the industry hence, health and safety at work place are important for moral, legal and financial reasons
6. Selective breeding is the process by which humans use animal breeding and plant breeding to selectively develop particular phenotypic traits by choosing which typically animal or plant males and females will sexually reproduce and have offspring together.
Advantages of selective breeding :
1. The possibility of gaining higher profit with the process. ... If plants or varieties bear abundant fruits or crops, they can be breed selectively to produce more crops that can be sold for higher profit.
2. It can eliminate control diseases in plants and animal
G.
1.During the caterpillar phase, the worm wraps itself in a liquid protein secreted by two large glands in its head. This secreted protein hardens upon exposure to the air. The resulting filament is bonded by second secretion, sericin, which forms a solid sheath or cocoon
2. We wear cotton clothes during summer as cotton absorbs sweat from the body, exposing to the atmosphere for easy evaporation. As we tend to sweat more during summer and cotton fabric absorbs sweat and help body to cool down.
3. The cocoons are often immersed in hot water to kill the pupae within the cocoon so as to prevent the breaking of the thread upon emergence as well as soften the secretin which holds the silk threads together.
4. This is due to abundant production of carbon monoxide during silkworm rearing, immersion of hands in boiling water for reeling the silk filament, and usage of harmful chemicals for dying and printing
5. Shearing doesn't usually hurt a sheep. It's just like getting a hair cut. However, shearing requires skill so that the sheep is shorn efficiently and quickly without causing cuts or injury to the sheep or shearer. ... In many countries, including the United States, there is a growing shortage of qualified sheep shearers.
Explanation:
Answer:
ok wait
for 5 years so I ll tell