Module 6: Genetic Change

• Mutations are changes to the DNA sequence.
• Gene flow refers to the movement of genes from one population to another due to the migration of individuals.
• A mutation can be caused by errors during replication, exposure to radiation or chemicals, viruses, or transposable elements.
• Genetic drift refers to changes in the genetic makeup of a population due to chance events.
• Point mutations involve substitution, deletion, insertion, or duplication of nucleotides within a gene.
• Frameshift mutations occur when an extra or missing base pair is inserted into or deleted from a gene, causing all subsequent codons to shift.
• Missense mutations result in amino acid replacements that may alter protein function.
• Non-disjunction occurs when chromosomes fail to separate properly during cell division, resulting in abnormal numbers of chromosomes in daughter cells.
• Silent mutations do not change the encoded amino acids but may affect mRNA stability or translation efficiency.
• Nonsense mutations cause premature stop codons, resulting in truncated proteins with altered functions.
• Inversion results in a reversed segment of DNA on a chromosome.
• Point mutation refers to changes at specific points within genes caused by errors during replication or exposure to mutagens.
• Chromosomal mutations involve large-scale structural changes in chromosomes such as deletions, duplications, insertions, inversions, translocations, and polyploidy.