define mutation

In biology, a mutation refers to a change in the DNA sequence that makes up a gene. DNA mutations can occur spontaneously, or they can be induced by various environmental factors such as exposure to radiation or certain chemicals. Mutations can take several forms, including substitutions, deletions, insertions, and duplications. Substitutions involve the replacement of one nucleotide with another, while deletions and insertions involve the loss or addition of one or more nucleotides, respectively. Duplications occur when a segment of DNA is copied and inserted in the genome, resulting in extra genetic material. Mutations can have a range of effects on an organism, from having no apparent effect to causing disease or altering an organism's physical or behavioral traits. In some cases, mutations may even be beneficial, allowing an organism to adapt to new environments or to perform new functions.