At which stage in its life-cycle does the silkworm yield the fibre of commerce?
- AEgg
- BLarva
- CPupaCorrect
- DImago
Explanation
The correct answer is C because the fibre of commerce, which is silk, is obtained from the cocoon spun by the silkworm. This cocoon is created during the pupa stage of the silkworm's life cycle. The larva, also known as the caterpillar, secretes a protein based fluid that hardens into silk threads to form a protective covering around itself as it transforms into a pupa. Therefore, the silk is harvested at this specific stage before the moth emerges.
Related questions
More UPSC Prelims practice from the same subject and topic.
- Prelims 2000GS1science-and-technology
A noise level of 100 decibels would correspond to
- Prelims 2000GS1science-and-technology
A ‘black hole’ is a body in space which does not allow any radiation to come out. This property is due to its
- Prelims 2000GS1science-and-technology
Consider the following features of newer models of motor cars: I. Radial tyres II. Streamlined body III. Multipoint fuel injection IV. Catalytic converter with exhaust Which of these features make the…
- Prelims 2000GS1science-and-technology
Fluorescent tubes are fitted with a choke. The choke coils
- Prelims 2000GS1science-and-technology
When a CD (Compact Disc used in audio and video systems) is seen in sunlight, rainbow like colours is seen. This can be explained on the basis of the phenomenon of
- Prelims 2000GS1science-and-technology
Assertion (A): A man standing on a completely frictionless surface can propel himself by whistling. Reason (R): If no external force acts on a system, its momentum cannot change.