Mutations may change the structure of a chromosome or just change a single nucleotide.
Dna is made up of nucleotides.
Mutations can change the structure of dna. .
What can change the structure of DNA?
[A] Mutations
[B] rays or beams
[C] Genes
[D] radiation
[E] DNA
[F] Smoking
[G] Microscope
[H] Chemicals