Question

Commercial silk is obtained from
A. Cocoon
B. Caterpillar
C. Adult moth
D. Both egg and adult moth

Answer 1

Hint: Sericulture, or silk farming, is the rearing of silkworms for the commercial production of silk.

Complete answer:
'Cocoon' or 'Pupa' stages of silk moths produce silk thread around the cocoon by their skin glands.
In commercial silk production, Silkworm larvae are fed with mulberry leaves, and, after the fourth molt, the cocoon goes to rest on a stem and spin their cocoons with silk. They have structural glands that produce a dense fluid that forms the fiber of the cocoon.

Additional Information:
There are five major types of silk of commercial importance, obtained from different species of silkworms found in India. These are:
- Mulberry silk: Mulberry silk comes from the silkworm, Bombyx mori, which solely feeds on the leaves of the mulberry plant. In India, it is produced in Karnataka, Andhra Pradesh, West Bengal, Tamil Nadu, and Jammu & Kashmir.
- Tasar (Tussah): It is copperish colored coarse silk. It is generated by the silkworm, Antheraea mylitta in the states of Jharkhand, Chattisgarh, and Orissa, Maharashtra, West Bengal, and Andhra Pradesh.
- Oak Tasar: It is the finer variety of Tasar silk generated by the silkworm, Antheraea poyeli which feeds on the oak plant, found in abundance in the sub-Himalayan belt of India covering the states of Manipur, Himachal Pradesh, Uttar Pradesh, Assam, Meghalaya, and Jammu & Kashmir.
- Eri: Eri silk is produced by the silkworm Philosamia ricini that feeds mainly on castor leaves. It is found mainly in the north-eastern states and Assam.
- Muga silk: It is golden yellow in color. It is obtained from the silkworm, Antheraea assamensis, found exclusively in Assam.

Note: Silk production also occurs in bees, wasps, ants, silverfish, beetles, etc. Other types of arthropods also produce silk, such as spiders but they are of negligible commercial use.