the silk fibre becomes hard when exposed to air
Answers
The silk yarn or silk thread is obtained from the cocoon of the silk moth.
When the protein matter remains inside the body of the silk-worm, it appears like a semi-fluid with an oil-like consistency. However, upon exposure to air, it becomes a hard fibrous substance. The worm in its caterpillar stage emits this fluid matter in small streams and the oxygen in the atmosphere converts it into silk fiber. The humidity or dryness in the atmosphere is the basis of formation of a perfect or a less-perfect silk fiber.
The caterpillar then covers itself completely with these silk fibers which hardens to form the cocoon, which is then used for obtaining the silk yarn.
Answer:
because....
Explanation:
When the protein matter remains inside the body of the silk-worm, it appears like a semi-fluid with an oil-like consistency. However, upon exposure to air, it becomes a hard fibrous substance