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EXAMPLES OF ANIMALS AND HUMANS MUTATION

over a lifetime our DNA can undergo changes or "mutation"in the sequence of base, A,C,G and T.

Thia results in changes in the protein that are made. Thin can be a bad or a good thing.

Mutations can occur during DNA replication if errors are made and not corrected in time.

Mutations can also occur as the result of exposure to enviromental factors such as smoking, sunlight and radiation.

Often cells can recognise any potentially mutation causing damage abd repair it before it become a fixed mutation.

Mutations contribute to genetic variation within species.

Mutation can also be inherited, particularly if they have a positive effect.

For example, the disoder sickle cell anemia is caused by a mutation in the gene that instructs the building of a protein called heaemoglobin. This causes the red blood cells to become abnormal, rigid, sickle shape. However,in African populations, having the mutation also protects against malaria.

Cancer is common human diseases; it is caused by mutations occuring in a number of growth controlling genes. Sometimes faulty,cancer causing genes can exist from birth, increasing a person's chance of getting cancer.