Changes

A '''Mutation''' is any change in a cell's DNA sequence. Mutations can occur in various ways; most commonly via radiation. Many mutations are detrimental to an organism's survival, such as sickle-cell anemia and cancer, but some increase an organism's possibility of reproducing and passing the beneficial mutated gene to future generations. This is a key part of the [[theory of evolution]].

'''Mutation''' is fundamental to the [[theory of evolution]].  According to the theory, mutations cause offspring to be slightly different from their parents.  Most mutations make the organism less fit, but some make it more fit.  The more fit individuals are more likely to reproduce and pass their mutated genes on to their offspring (see [[natural selection]]). 

 

In [[biology]] mutation is any physical change in the [[genetic material]] of an [[organism]]. In most cases this is either the [[DNA]] or [[RNA]] in the cell [[nucleus]]. In multicellular organisms there are two primary classes of mutation, [[germline mutations]] and [[somatic mutations]]. Germline mutations are those changes that can be passed down to offspring, while somatic mutations are mutations that only alter genetic material in the mutated organism. There is some evidence that changes outside of the cell's genetic material, such as the [[cytoplasm]], [[proteins]], or the cell [[membrane]] can also be inherited.

 

Mutations can be caused by internal or external factors. Common external factors include [[ultraviolet]] radiation, chemical [[mutagens]], or parasitic organisms (such as [[viruses]] or [[bacteria]]). Most internal causes of mutations stem from errors in reproduction of genetic material. Most of these errors are corrected by error-correcting [[ribosomes]].

 

Some organisms will respond to harsh environments by increasing the rate of mutations. This is known as [[hypermutation]] and is hypothesized to aid organisms by creating wider variation in the [[gene pool]] of the population, increasing the chances that at least some decedents might survive under harsh conditions. 

 

 

[[Category:Biology]]