1. Forensics Chp. 12 DNA Analysis
DNA Structure
Forensics
Chp. 12
DNA Analysis

2. DNA Structure
A gene is a long section of a DNA molecule whose sequence of building blocks specifies the sequence of amino acids in a particular protein.
Protein- fundamental component of living cells
Enzymes
Hormones
Antibodies
Hemoglobin
Insulin

3. How does DNA work DNA (nucleic acid)  RNA  Ribosome Amino Acids 
Protein  Do a job (perform a function)
An Analogy can help you remember this:
Come up with your own…(5 min.)
Ex: Build a house
DNA is the blue prints (instructions)
Amino Acids are the lumber
Proteins are the house…

4. DNA Structure View from the side - Helix
Partially unwound double helix so you can see components

5. Views from the top
Model
X-Ray
Photo-51

6. DNA composed of nucleotides
Sugar (deoxyribose)
Phosphate group
Nitrogenous bases
A - T
C - G

7. A 5 C sugar and a phosphate group form the backbone
DNA Structure
A 5 C sugar and a phosphate group form the backbone

8. Nitrogenous bases DNA Structure A, T, C, & G
make up the rungs on the ladder

9. Complimentary Base Pairing
Bases held together with Hydrogen bonds- WEAK BONDS
Guanine pairs with Cytosine
Triple bond
Adenine pairs with Thymine
Double bond

10. DNA Structure
3D Video Clip (Click next 4 times)

11. 3 methods to analyze DNA
RFLP- Restriction Fragment Lengths Polymorphism
Restriction enzymes cut DNA up
Not best method because we need a lot of DNA
PCR – Polymerase Chain Reaction
Polymerase – enzyme that replicates (makes more) DNA
STR – Short Tandem Repeats
Specific sequences of DNA fragments that are repeated at a particular site on a chromosome

12. Replication Technology
Mitochondrial DNA- from mom only
good for hair, teeth, and bone
PCR-
Perhaps the most successful technology to ever emerge from LIFE SCIENCE!!!
Many Uses
Forensics-
blood, convict, exonerate false accusations
Agriculture, Vet., Medicine, Envi. Sci.,
Microorganisms, viruses, parasites…