Five environmental factors that can cause mutations include ionizing radiation, certain chemicals, and infectious agents. These are known as mutagens.
Environmental Mutagens
Mutagens are agents that can alter DNA and increase the frequency of mutations. These agents can be physical or chemical.
Here are five environmental factors that can lead to mutations:
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Ionizing Radiation: According to the reference, ionizing radiations such as X rays, gamma rays, alpha particles, UV radiations and radioactive decay act as mutagens. These high-energy radiations can directly damage DNA by causing breaks in the DNA strands or by modifying DNA bases.
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Ultraviolet (UV) Radiation: UV radiation, specifically UVB and UVC, is a component of sunlight. It can cause mutations by promoting the formation of pyrimidine dimers, which are abnormal linkages between adjacent pyrimidine bases (thymine or cytosine) in the DNA sequence.
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Chemicals (Alkylating Agents): Chemicals that react with DNA molecules such as alkylators include ethyl methane sulfonate, methyl methane sulfonate, di ethyl sulfonate and nitrosogaunidine. These chemicals add alkyl groups (e.g., methyl or ethyl groups) to DNA bases, altering their structure and causing mispairing during DNA replication.
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Infectious Agents: The provided text mentions infectious agents without specifics. Certain viruses and bacteria can insert their genetic material into host cells, disrupting normal gene function and potentially causing mutations. Some viruses can also trigger inflammation and oxidative stress, further contributing to DNA damage.
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Radioactive Decay: The reference states that radioactive decay act as mutagens. Radioactive materials emit ionizing radiation that can directly damage DNA.
