While blizzards often feature extreme cold and heavy snow, there are actually no temperature or snow depth requirements for a storm to qualify as a blizzard. Occasionally, blizzard conditions will present when there is no precipitation.
Definition. A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. A Mutagen is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed.efinition. A Mutation occurs when a DNA gene is damaged or changed in such a way as to alter the genetic message carried by that gene. A Mutagen is an agent of substance that can bring about a permanent alteration to the physical composition of a DNA gene such that the genetic message is changed.
Best Answer: Mutagen: a substance that causes mutation, i.e. that causes changes in genes. Teratogen: Substance that deforms the fetus in the womb and so induces birth defects. Carcinogen: a substance that causes cancer. All of them give undesirable defects in human beings, the difference is obvious from the definitions.