1. Mutation

2. Gene Mutations change in the nucleotide sequence of a particular gene
Types: inverted, deleted, duplicated or moved to another spot
WHY???????
Sometimes occur spontaneously
Chromosome changes during meiosis can cause changes in the genetic information.
Occur because of mutagens
Chromosome changes, sometimes leading to genetic disease or death, can be cause by mutagens such as radiation or chemicals
Can occur if there is failed separation of chromosomes in meiosis
Failed separation means that a gamete may end up with no chromosome or too many of a chromosome Zygotes that result from these gametes rarely survive, and if they do, they will have serious genetic disorders
Gene mutation may lead to alter the number or the structure of the entire chromosome, which could lead to chromosomal mutations

3. Chromosomal Mutations
Karyotype are used to study an individual’s chromosomes
Chromosomes are identified and paired by size, centromere location and banding patterns.
Chromosomal mutation is a large-scale alteration of the chromosomes of an organism, where either the number or the structure of chromosomes is changed.
Genetic disorders or syndromes can occur
Down syndrome usually occurs when there is an extra 21st chromosome