how is genetic variation related to mutation?

Question

I need an answer by tuesday. so please hurry! thanks! (:

Answer 1

Mutations can lead to genetic variation. Mutations are changes in the nucleotide sequence in the genes that are induced by various factors such as chemicals, radiation, or it can occur spontaneously, as the result of the error that occurs in the synthesis of nucleotides (in replication for example), but this occurs rarely. The changes caused by mutations eventually build up (if it is not deleterious, or not excised by the cell's genetic control mechanisms) and cause genetic variation in a certain population.

Answer 2

The animals and plants on earth are diverse. From our primitive age till the present age the biological world has been evolving and will continue to evolve. If it wasn't for evolution, there wouldn't have been diverisity, varieties of so many species that we see. All thanks to genetic variation.
We know that a gene can develop a phenotypic character, which means that the physiological, biochemical, phenotypic, behaviourial characters all depend on the genes that an organism constitute. If there is a slight change in the genes, that will surely result in changes in all the characters of the organism, which may be beneficial for it or lethal. This is how the organism is able to adapt to the changes in the environment and thus is able to survive and is selected by nature for producing future healthy generations (natural selection).
So, talking about the changes occuring in genes could be due to mutation which results from environment factors in nature and is artificially done too. And it is also due to genetic recombination (crossing over) that occurs during gamete formation which results in variety of genes combined together in a homolog which gets incorporated in the offsprings, gradually making the organism evolve.

Answer 3

What you are asking about variation may be polymorphism. Traits undergo selective pressure just as mutations do. In order for a trait to become established in a population there must be positive pressure.
In one situation the expressed trait 'A' will do well combined with 'a' but not 'b'. While trait 'B' does well with 'b' but not 'a'
For example, one type of male might do better with one type of female, another type of male might do better with another type of female, and the frequencies of the two types of female might be such that the two types of male do equally well on the average. This implies that patterns of dominance can determine whether polymorphism is maintained.
polymorphism (pol-ee-mor-fiz-um) [Gk. polus, many + morphe, form] The coexistence of two or more distinct forms (polymorphic characters) in the same population. Variant forms of a particular gene that occur simultaneously in a population.
Balanced polymorphism is maintained by natural selection. Two distinct forms of the same gene that are selected by certain situations from one population. The human blood groups are examples of polymorphism.
This is not dominance in the Mendalian sense. It is rather dominance in the sense of advantage. Genes have numerous effects so genes are of importance to the organism by possessing an overall advantage or disadvantage very seldom are they neutral.
Mutations though can be positive, negative, or neutral (silent).
Selection acts simultaneously at all levels of an organism.

http://www.eurekalert.org/pub_releases/2001-10/uoc--sva101701.php

http://www.genetics.org/cgi/content/abst...
http://www.bulbnrose.com/heredity/ford/f...
http://www.answers.com/topic/polymorphis..