Реферат: Evolution Essay Research Paper We actlike animals

characteristics. Over a long period of time, genetic drift is able to gradually

alter the genetic features of a population.

As time goes on, evolution can change in two distinct manners. Evolution can be

altered through the most common aspect of natural selection. On the contrary,

evolution can also be altered through mutation. Mutation outputs random

differences in the genetic features of a species or a population. A population

is an accumulation of individuals, which are of the same species and live in

the same habitat or area. Mutation is an altered gene. A gene is the basic and

main unit of hereditary. Inherited characteristics of an organism is altered

from mutations.

Chromosomes are threadlike structures, which transport hereditary

characteristics. DNA, the coded information that determines hereditary

characteristics, is carried in large numbers by chromosomes. The majority of

animals and plants contain a full set of paired chromosomes. Human body cells,

for instance, have forty-six chromosomes, or twenty-three pair. During cell

division or reproduction, each offspring receives half the set of chromosomes

from each parent. Mutations can most likely be caused by environmental factors,

with factors such as chemicals or radiation. Chemicals and radiation alter DNA

genes and even create errors during the replication of DNA during cell

division. Nearing the end of cell division, the gene has changed and duplicates

itself in the altered form. Only a mutated gene can introduce new hereditary

characteristics. Mutations are not only the building blocks of evolutionary

change, but also, are the building blocks of the development of new species.

The majority of mutations tend to create adverse traits, such as, albinism.

Albinism is a mutation that contains mutant genes, which lack the ability to

generate normal skin pigment. Animals and plants, which contain the albinism

gene, are unable to survive and reproduce as much and as well as the animals

and plants without the albinism gene. Thus stating, that organisms with a mutant

gene, will be unable to survive and reproduce as well as the organisms without