Short Answer 
Mutations are DNA sequence changes caused by various factors, and their types include point mutations, chromosomal rearrangements, and non-disjunction. Point mutations alter one base pair without changing total DNA, while chromosomal rearrangements and non-disjunction can lead to increased genetic material, affecting traits and health.
Step 1: Understanding Mutation Types
Mutations are changes in the DNA sequence that can happen due to various factors such as copying mistakes during cell division, exposure to ionizing radiation, or chemicals. There are different types of mutations, each affecting DNA in unique ways:
- Point Mutation: Affects a single base pair but does not change the total amount of DNA.
- Chromosomal Rearrangement: Involves structural changes in chromosomes, often increasing the genetic material.
- Non-Disjunction: Occurs when chromosomes fail to separate properly, leading to extra chromosomes in cells.
Step 2: Effects of Point Mutation
A point mutation is a small alteration in the DNA sequence, impacting just one base pair. Due to its limited scope, it usually doesn’t affect the total quantity of DNA present in the organism. This type of mutation may result in changes to genetic traits but does not add or remove genetic material from the organism.
Step 3: Consequences of Chromosomal Rearrangement and Non-Disjunction
Both chromosomal rearrangement and non-disjunction significantly affect the amount of DNA in a cell. Chromosomal rearrangements can lead to the gain of chromosomes or segments, while non-disjunction causes cells to have an extra chromosome. These changes can result in variations, such as increased genetic material, which can influence an organism’s traits and health.