Answer : It is important to boil cocoons to obtain silk fibers. … If cocoon is not boiled, the fibres obtained will be brittle, and we will get fragments of the thread instead of a long continuous silk thread. Moreover, it would be impossible to spin it into a thread.
What does the boiling of the cocoons do?
During boiling, some amount of water enters the cocoon cavity and makes it soft. This helps in separating the fibres from cocoon during the reeling process. During the reeling process, if pupa tries to come out of cocoon, the fibre may be damaged.
Why do we need to boil the cocoon for extraction of silk?
The cocoons are placed into boiling water in order to soften and dissolve the gum that is holding the cocoon together. This is a crucial step in the silk production process as it ensures that there is no damage to the continuity of each thread.
Why are silk cocoons boiled give two reasons?
Silk is produced by silk worms when making their cocoons. To get the silk from the cocoons at the optimum time, before the worm makes a hole in the cocoon reducing it’s value, they are placed in boiling water to kill the worm and make it easier to unwrap the silk threads.
Why are the cocoons boiled in hot water or treated in ovens Class 7?
Cocoons are boiled in hot water or treated in ovens so as to get the silk. Boiling with hot water or treating in ovens results in softening of the upper layer of of the cocoon or killing the pupa inside.
Can you get silk without killing the worm?
It allows the completion of the metamorphosis of the silkworm to its moth stage, whereas most silk harvesting requires the silkworms to be killed in their cocoon stage. No animals suffer or die for the silk to be produced, making it a favorable alternative to normal silk for those who do not believe in harming animals.
Why silkworms are killed by placing the cocoons in hot water?
Explanation: Because there is a worm inside the cocoon so that’s why it is boil to kill it . … When the silkworms are still in their cocoons they are boiled out so that they would die inside. …
How do you boil a silkworm cocoon?
- Cocoons are put into a pan of boiling water. The groping ends of the cooked cocoon can be completed with the stirring rod in the pan (see Appendix, Figure 14).
- The cocoons contained in the wire cage are placed into the boiling water and then boiled for a few minutes.
Who invented silk?
According to Chinese legend, Empress His Ling Shi was first person to discover silk as weavable fibre in the 27th century BC.
Why are cocoons Stiffled?
Stifling treatments are applied to silk cocoons in order to kill the pupae, preventing the emergence of moths and allowing to preserve the silk during long periods of time. All of them involve the application of aggressive steps, such as sun exposure, hot steam from boiling water or hot air, during hours or even days.
Does boiling water kill worms?
Boiling drinking water for 1 minute to kill the parasite. This will ensure safe drinking water during community-wide outbreaks caused by contaminated drinking water.
Why are silk cocoons not boiled?
Why are some cocoons not boiled during the harvesting of the silk thread? Some cocoons are not boiled during the harvesting of silk thread because they are let to grow into pupae. This pupae will then help in the future harvesting of silk when they grow into a moth.
Why do we not wait for the silk moth to hatch and then boil the cocoon?
When the silk worms become an adult moth , during the process when the moth comes out of the cocoon, it releases a spit which dissolves the silk in the cocoon so that it can come out thereby destroying the silk itself. Hence the farmers cannot wait for the cocoon to hatch.
What is rearing of silkworms called?
Sericulture is the science that deals with the production of silk by rearing of silkworm.
Why cocoon of silk moth are kept under sun or boiled or exposed to steam?
Answer: Cocoons of silk moth are used to obtain the silk fibres. These cocoons are kept under the sun or boiled or exposed to steam. … This process of obtaining wool from the cocoons is called reeling the silk.