Final answer:
A mutation is any permanent alteration in the DNA sequence of a cell, caused by mistakes during DNA replication or environmental mutagens like UV light and chemicals. Mutations can result in a range of effects from benign to harmful, and are a key factor in the development of diseases like cancer. The term 'mutagenesis' describes the process of mutation occurrence, whether spontaneous or induced.
Step-by-step explanation:
Understanding Mutation
A mutation is a change in the DNA sequence within an organism’s genetic material. Mutations can happen by errors in DNA replication or through exposure to various environmental agents like X-rays, UV rays, chemicals, and viruses, which are collectively known as mutagens. Two primary types of mutations are identified, spontaneous mutations, which occur naturally within cellular processes, and induced mutations, which are caused by external factors like environmental mutagens. Mutations can affect cell functions negatively, altering the way cells grow and divide, and can sometimes lead to diseases such as cancer.
Mutagens like UV radiation can cause direct DNA damage, like pyrimidine dimers, leading to disruption in DNA replication and transcription, which if uncorrected, can result in permanent mutations. On the other hand, when mutations occur during the stages of meiosis or mitosis, they can lead to various disorders and diseases depending on whether they are somatic or germline mutations.
In terms of cancer, mutations that drastically alter the function or structure of key proteins can lead to uncontrolled cell growth and the formation of tumors. These can be benign or, if they breach tissue confines and metastasize, malignant, and are categorized based on the tissue of origin (carcinomas, myelomas, leukemias, sarcomas).