dnaIt’s an individual sort of thing

What does DNA mean?

D- deoxyribo

N- nucleic

A- acid

Deoxyribonucleic Acid

Where can you find DNA?

Chromosomes found in the nucleus of every single one of your cells contain DNA

What can it tell you?

DNA is different in each person, so a DNA sample can be matched to an individual.

What Does it Look Like?

Sugar & Phosphate Backbone

Nitrogenous Bases

Twisted Shape is a Double

Helix

A little more about it…The Nitrogenous Bases are:

Adenine Thymine Cytosine Guanine

Abbreviated: A T C G

Here’s how they pair:

A-T and C-G

TWO TYPES OF DNA

Mitochondrial- found in the mitochondria of cells; it can only reveal the mother’s line of inheritance, not an individual.

Nuclear- found in the nucleus of cells; it can reveal the specific individual from which it came.

Can it be found in blood?

YES!

White blood cells have a nucleus; therefore, they contain DNA.

What about cheek cells?

YES!

Cheek cells have them, too.

Forensic DNA Analysis• Technique used in genetic

fingerprinting and paternity testing

• Restriction enzymes are used to cut the DNA into smaller pieces.

• Gel Electrophoresis is used to separate the DNA fragments

• The result is a DNA fingerprint

Here’s how it works…

1. A sample of DNA is isolated from body cells.

2. The DNA is cut into fragments at specific locations using Restriction Enzymes.

3. The DNA is injected into electrophoresis gel, an electric current is applied, and the fragments move along the gel.

The Result of Gel Electrophoresis

The gel is treated with a dye and the DNA fragments appear as bands on the gel.

What do the bands mean?The smallest

fragments move farther than the larger ones.

The banding pattern is the “DNA Fingerprint”

Which patterns match?

If a “column” has the exact same banding pattern, a match has been found!

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