| Mutations | Permanent change in the nucleotide sequence of DNA |
| Somatic Mutation | Mutation occuring in a body cell - not passed on to offspring |
| Gametic Mutation | Mutation occuring in a sex cell - heritable, form new alleles - cause variation |
| Point Mutation | Change, deletion, or insertion of a singular nucleotide base during replication |
| Frameshift Mutation | Occurs when theres a deletion or insertion as this completely shifts the mRNA sequence of 3 codons, shifting all subsequent sets of 3 |
| Mutagen | Physical, chemical or biological agent causing mutation |
| UV/Radiation Mutagen | High energy waves ionise atoms → DNA damaged = mutation |
| Temperature Mutagen | Breaks bonds between deoxyribose sugar → mutates |
| Chemical Mutagen | Base analogues mimic and insert themselves into DNA bases |
| Non-Disjunction Mutations | Homologous chromosomes or sister chromatids fail to separate → daughter cells contain wrong number of chromosomes [Aneuploidy] |
| Monosomy | Form of aneuploidy wherein one chromosome is missing [Turner Syndrome] |
| Trisomy | A form of aneuploidy in which a homologous set contains an extra chromosome [3 instead of 2] |
| Trisomy-21 | Down Syndrome: Set 21 has 3 chromosomes |
| Mosaicism | Somatic mutation in which an individual has two genetically different sets of cells in their body |
