TASK DEFINITION: Given scientific fact as input, generate the question from this fact such that it can be answered from the input.
PROBLEM: Rubber is an example of a(n) insulators that does not allow electrons to move through them.

SOLUTION: Rubber is an example of what type of substances that do not allow electrons to move through them?

PROBLEM: The newest, outer layers of secondary xylem are called sapwood.

SOLUTION: What are the newest, outer layers of secondary xylem called?

PROBLEM: The relationship between a nucleotide codon and its corresponding amino acid is called genetic code.

SOLUTION:
The relationship between a nucleotide codon and its corresponding amino acid is called what?