Which substance was developed by chemists

Silk is made by moth larvae, asprin is derived from tree bark, nylon was made initially in a labratory, but asprin and even synthetic silk can be produced by chemist.

Silk is made by moth larvae, aspirin is derived from tree bark, nylon was made initially in a laboratory, but aspirin and even synthetic silk can be produced by chemists. Of the three, only nylon has no naturally occur source.