Mutations 7.L.4A.5 Construct scientific arguments using evidence to support claims for how changes in genes (mutations) may have beneficial, harmful, or neutral effects on organisms.

Blue eyes are a common mutation Any change in the genes of an organism Can have beneficial, harmful, or neutral effects on organisms Some can be both beneficial and harmful Blue eyes are a common mutation What are mutations?

Causes of mutations Can occur Examples of environmental factors that can cause mutations Causes of mutations Can occur Randomly- during DNA replication or transcription (when DNA is copied to make RNA) As a result of environmental exposure-

Beneficial mutations Changes that may be useful to organisms in different or changing environments. Result in phenotypes that are favored by natural selection and increase in a population Natural selection- being able to adapt as a result of environmental pressures (climate change, predation, etc.)

Harmful mutations Harmful mutations may cause genetic disorders or cancer. Effect an organisms ability to survive

Both beneficial and harmful Sickle cell anemia Harmful- causes organ damage and chronic pain Beneficial- mutation that protects humans from Malaria

Most are automatically repaired by an organism’s enzymes (proteins made by cells) and have no effect. Neutral mutations

When the mutation is not repaired, the altered chromosome is passed to all replicated cells that come from the mutated cell. Could benefit or harm the organisms and future generations If the mutated cell is a body or somatic cell, all cells that are replicated from it will be affected, but it will not be passed to the offspring of the organism Mutations continued

If the mutated cell is a sex cell or gamete, the altered cells can be passed to future generations and result in genetic disorders Mutations continued