What causes DNA mutation? | HowStuffWorks
2023年10月16日 · In our bodies, a mutation refers to a change in the DNA sequence, which is the intricate order of genetic material. While there are mutations that can be disruptive or even harmful (akin to a broken traffic light), many are neutral and others can be incredibly beneficial.
Mechanisms of DNA damage, repair and mutagenesis - PMC
DNA damage can be categorized into two main classes based on its origin: endogenous and exogenous. The majority of the endogenous DNA damage arises from the chemically active DNA engaging in hydrolytic and oxidative reactions with water and reactive oxygen species (ROS), respectively, that are naturally present within cells.
The causes of mutations - Understanding Evolution
Mutations – changes in the genetic sequence of DNA or RNA – are the raw material for evolution. Natural selection, genetic drift, and other evolutionary processes act on genetic variation – and that genetic variation starts with mutation.
10.1: Mutations - Causes and Significance - Biology LibreTexts
2022年5月15日 · In the living cell, DNA undergoes frequent chemical change, especially when it is being replicated (in S phase of the eukaryotic cell cycle). Most of these changes are quickly repaired. Those that are not result in a mutation. Thus, mutation is a failure of DNA repair.
DNA Damage and DNA Repair: Types and Mechanism - Microbe …
2023年9月8日 · DNA is the basic unit of inheritance that maintains the integrity and function of living organisms. However, it is constantly exposed to damaging agents which can cause DNA damage. Additionally, errors can occur during DNA replication and repair processes, leading to harmful mutations.
Mutation | Definition, Causes, Types, & Facts | Britannica
2024年11月5日 · Mutation, an alteration in the genetic material (the genome) of a cell of a living organism or of a virus that is more or less permanent and that can be transmitted to the cell’s or the virus’s descendants. The genomes of organisms are all composed of DNA, whereas viral genomes can be of DNA or RNA.
Errors in DNA Replication | Learn Science at Scitable - Nature
Today, scientists suspect that most DNA replication errors are caused by mispairings of a different nature: either between different but nontautomeric chemical forms of bases (e.g., bases with an...
DNA Repair - Molecular Biology of the Cell - NCBI Bookshelf
When DNA repair is complete, the expression of the SOS genes is repressed, the cell cyle resumes, and the undamaged DNA is segregated to the daughter cells. Damaged DNA also generates signals that block cell-cycle progression in eucaryotes.
Mutations Are the Raw Materials of Evolution - Nature
A mutation is a change in the sequence of an organism's DNA. What causes a mutation? Mutations can be caused by high-energy sources such as radiation or by chemicals in the environment.
The central role of DNA damage in the ageing process | Nature
2021年4月28日 · The strong mechanistic link between DNA damage and ageing, and the role of DNA as the primary template for all cellular functions, suggest DNA damage as a candidate for the primary cause of...