Cornell notes on page 48 Standard: Describe how techniques such as DNA fingerprinting, genetic modification, and chromosomal analysis are used to study the genome. EQ: How is technology used to study genomes?

A genome is an organism’s complete set of genes (DNA).  Techniques like DNA fingerprinting and karyotyping are often used to study the genomes of different organisms.

A DNA fingerprint is an image of an organism’s DNA sequence. DNA fingerprints are obtained through a process called gel electrophoresis. This process cuts the DNA strand into pieces and separates them by size. DNA fingerprints can be used to determine whether two organisms are related. They can also be used in criminal investigations – scientists compare DNA samples left at crime scenes to samples from suspects to see if they match.

Nondisjunction occurs when chromosomes do not separate properly during meiosis. non = not dis = apart junction = connection The chromosomal abnormalities caused by nondisjunction can be seen in a karyotype. Karyotypes are pictures of an organism’s chromosomes, set up in numbered pairs.

Trisomy is the most common chromosomal abnormality in humans. Trisomy means a person has three copies of a particular chromosome. The disorder is named for which chromosome is tripled (ex. Trisomy 21, Trisomy 13, Trisomy 18). Trisomy 21, or Down’s Syndrome, is the most common form. The severity of a genetic disorder depends on which chromosome is affected. For example, babies with Trisomy 13 or 18 usually die before age 1, but those with Down’s Syndrome have an almost normal lifespan.

FAQ Do I glue on the on the top of the existing chromosome or to the side of it? ◦To the side I have an extra chromosome that does not match anything! Where do I put it? ◦That is the sex chromosome, glue it next to chromosome 23 I have 3 of one chromosome… whats the deal? ◦That is your trisomy, find the genetic disease using the chart at the bottom of page one