Subject :NSO Class : Class 7
Which of the following stages in the life history of a silk moth produces silk fibres?
A 
B 
C 
D 
the answer to this question is c r d please tellme
Ans 1:
Class : Class 7
I thought the silk is obtained from the cocoon
Ans 2:
Class : Class 7
Ans 3:
Class : Class 8
No, the answer is 'C' only. In pupa stage the silk fiber is only obtained, but actually it is produced by larva and in question it is asked which stage produces fiber. Hence, the answer is 'C".
Ans 4:
Class : Class 8
as larva produces and when it is fully produced it forms a cocoon
Ans 5:
Class : Class 7
IT IS 'D' BECAUSE AT COCOON STAGE THE CATERPILLAR PRODUCES SILK FIBRES AND KNOTS AROUND IT AND COVERS HIMSELF.AFTER SOME TIME THE SILK FIBRES GETS HARDEN DUE TO THE GUMMY SUBSTANCE WHICH THE CATERPILLAR PRODUCES............IT IS CALLED "FIBROIN" WHICH IS MADE UP OF PROTEINS.ON HEATING THE COCOONS IN WATER THE SILK AGAIN BECOMES SOFT AND IS EXTRACTED FROM COCOONS........THIS PROCESS IS CALLED "REELING OF SILK"
Ans 6:
Class : Class 7
OPTION C
Ans 7:
Class : Class 7
it is c because the silk has already started getting produces when it is larva
Ans 8:
Class : Class 7
it must be c . at cocoon stage silk is already produced
Ans 9:
Class : Class 6
answer is c because in the pupa stage the silk is already produced and in the larvae stage it produces silk when it is ready to go in the next stage of its life
Ans 10:
Class : Class 7
the answer is d only in the cocoon stage they are heated in the hot water so that the reproducing caterpillar will die and it will be very easy to extract silk fiber from it.
Ans 11:
Class : Class 7
ans:c,you may think d,but only in larval stage it produce silk in option d it is in a cocoon stage it cannot produce silk
Ans 12:
Class : Class 8
no it is c
Ans 13:
Class : Class 8
also felt d but explanation provided above makes me feel c