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.
> (struct paper (journal) #:super struct:document) If the #:mutable option is specified for an individual field, then the field can be mutated in instances of the structure type, and a mutator procedure is bound. Supplying #:mutable as a struct-option is the same as supplying it for all fields.