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.
Metaplasia (Greek : change in form) is the reversible replacement of one differentiated cell type with another mature differentiated cell type.The change from one type of cell to another may generally be a part of normal maturation process or caused by some sort of abnormal stimulus.etaplasia (Greek : change in form) is the reversible replacement of one differentiated cell type with another mature differentiated cell type.