This set of Class 12 Biology Chapter 9 Multiple Choice Questions & Answers (MCQs) focuses on “Food Production Strategies – Sericulture”.
1. What is sericulture?
a) Rearing of fishes
b) Rearing of silkworm
c) Rearing of birds
d) Rearing of cockroach
Explanation: Sericulture is the breeding and management of insects for the production of silk. Silk is of two main types-mulberry silk or cultivated silk and non-mulberry silk or wild silk.
2. Which of the following varieties of silk is not produced in India?
a) Muga Silk
b) Mulberry Silk
c) Tassar Silk
d) American Silk
Explanation: Four varieties of silk produced in India are natural silk, mulberry, tassar, eri and muga. India ranks third among the mulberry silk-producing countries of the world.
3. Which of the following is not considered as a silk city of India?
Explanation: India’s silk industry is the world’s second-largest contributor to 18% of the total raw silk production. The cities contributing for such growth of silk are Kanchipuram in Tamil Nadu, Bhagalpur in Bihar, Pochampally in Telangana. They are called silk cities in their respective states.
4. Which of the following is not the characteristic feature of Tassar silk?
a) Also known as Kosa silk
b) Obtained from Bombyx mori
c) A native of India and China
d) Larvae of the silkworm feed on oak
Explanation: Tassar silk is also known as Kosa silk. It is obtained from the oak-feeding larvae of the silk moth-Antheraea mylitta. It is a native of India and China. Tassar cocoons are attached by a peduncle to twigs of Sal trees.
5. Which of the following silk is mainly produced in Assam?
a) Arundi silk
b) Natural silk
c) Muga silk
d) Tassar silk
Explanation: Muga silk is produced by the larva of Antheraea assamensis in Assam. It is golden yellow in colour and superior to tassar silk in gloss and other qualities. It is an excellent material for embroidery.
6. Which of the following is not a characteristic feature of Eri silk?
a) Also known as Arundi silk
b) Produced in Bengal, Bihar and Assam
c) Cocoons are soft and white
d) Larva feeds on oak leaves
Explanation: Eri or Arundi silk is produced by the larva of Philosamia ricini and is made in Bengal, Bihar and Assam. The eri silkworms feed on castor leaves and are reared indoors. The cocoons are soft and white or yellowish.
7. How many stages are there in the life cycle of a silkworm?
Explanation: The life history of silk moth passes through four stages-egg, larva, pupa and adult. About 50% of the cocoon are kept in boiling water to kill pupa and then thread is reeled off. Rest 50% are kept as such so that they become adult and the life cycle starts once again.
8. Cocoon is formed by how many pairs of glands?
Explanation: The cocoon is formed by two pairs of glands. One pair of glands form a protein fibroin which forms twin filaments and other pair of glands form a protein sericin which is responsible for joining of twin filaments.
9. Raw silk is prepared by degumming.
Explanation: Silk containing sericin is called as raw silk. Sericin is a gummy substance which is usually retained as it gives protection to silk during processing. So in order to obtain Pure silk, sericin is chemically removed. This makes the silk soft and also reduces its weight.
10. Which of the following state is not a mulberry silk manufacturer in India?
c) Andhra Pradesh
d) Tamil Nadu
Explanation: In India, 97% of the raw mulberry silk is produced in Karnataka, Andhra Pradesh, Jammu and Kashmir, Tamil Nadu and West Bengal. The non-mulberry silk industry is found in Assam, Bihar, Bengal, Odisha and Madhya Pradesh. There are three main types of silk- Tassar silk, Muga silk and Eri silk.
11. Pebrine disease in silkworms is caused by a fungus.
Explanation: Pebrine disease of silkworms is caused by a protozoan Nosema bombycis. Fungus Spicaria and Botrytis cause Muscardine. Flacherie disease of silkworms is caused by a virus.
Sanfoundry Global Education & Learning Series – Biology – Class 12.
To practice all chapters and topics of class 12 Biology, here is complete set of 1000+ Multiple Choice Questions and Answers.
- Get Free Certificate of Merit in Biology - Class 12
- Participate in Biology - Class 12 Certification Contest
- Become a Top Ranker in Biology - Class 12
- Take Biology - Class 12 Tests
- Chapterwise Practice Tests: Chapter 1, 2, 3, 4, 5, 6, 7, 8, 9, 10
- Chapterwise Mock Tests: Chapter 1, 2, 3, 4, 5, 6, 7, 8, 9, 10