1. Problem and Word of the Day
POD: Read p. 158 “DNA Fingerprinting”. Summarize the outcome of the case in 2-3 sentences.
WotD: Allele

2. Video on DNA

3. Exit Ticket and Homework
Exit Ticket: Answer the 4 post video questions
Homework: Complete questions for homework

4. Unit 7 DNA

5. Problem and Word of the Day
POD: Is DNA Class or Individual evidence? Why?
WotD: Chromosome

6. Objectives of Unit 7: DNA
Explain how crime scene evidence is collected and processed to obtain DNA
Describe how radioactive probes are used in DNA fingerprinting
Explain how DNA evidence is compared for matching
Explain how to use DNA fingerprinting to identify DNA from a parent, child, other relative, or a non-related individual

7. Notes History of Biological Evidence in Forensics
DNA Double Helix was discovered by Watson and Crick
DNA Evidence has been used since the 1980s
Dr. Alec Jeffreys (1984) identified that different people had different polymorphisms and created technique to DNA Fingerprint
The Innocence Project began in 1992
Facts about DNA fingerprinting: Also known as DNA profiling
Used with a high degree of accuracy
Biological evidence is examined for the presence of inherited traits
Identical twins are the only ones with the same DNA profile
Uses: solve crimes, paternity testing, identify victims of war and disasters.
23 pairs (46 total) chromosomes in the nucleus of most human body cells. (except the egg and sperm – 23 only)
Half of the chromosomes come from mom and half from dad
Mitochondrial DNA doesn’t change, passed down from mom

8. Notes C. The Function and Structure of DNA
DNA contains the genetic material of a cell
Chromosomes are located in the cell nucleus
Chromosomes contain long DNA strands wrapped around proteins
Nitrogenous Bases—pairs of molecules that form the rungs of the DNA “ladder”
Four types of Bases
A (adenine)
C (cytosine)
G (guanine)
T (thymine)

9. Notes 6. Base-Pairing Rules adenine (A) binds only with thymine(T)
Cytosine (C) binds only with guanine (G)
Draw the following using color into your notes

10. Exit Ticket and Homework
Exit Ticket: What would the opposite strand be if I had a DNA strand of ATTGACATGC
Homework: Find a case that was solved using DNA evidence and summarize into one paragraph

11. Problem and Word of the Day
POD: Name three items that can contain DNA from a human body.
WotD: DNA Fingerprint

12. Extra Credit Case Presentations
In 1-2 minutes summarize what happened in the criminal case that used DNA to solve the case

13. Notes
7. DNA Identification a. Polymorphisms: Non-coded DNA that contain unique patterns of repeated base sequences that are unique to individuals b. DNA Fingerprinting (Profiling) isolates and analyzes polymorphisms c. DNA fingerprints appear as a pattern of bands on X- ray film

14. Notes
8. DNA Profile a. Two types of repeating DNA sequences 1. Variable Numbers of Tandem Repeats (VNTR) - The number of repeats varies from person to person - 9 to 80 bases in length 2. Short Tandem Repeats (STR) - 2 to 5 bases in length - Shorter lengths make STRs easier to use than VNTRs 3. VNTR and STR data are analyzed for - tissue matching - inheritance matching

15. Notes
9. DNA Profile Matching a. Tissue Matching - Two samples that have the same band pattern are from the same person b. Inheritance Matching - Each band in a child’s NDA fingerprint must be present in at least one parent

16. Notes
10. DNA Population Databases a. Population genetics - the study of gene variations among groups of individuals - analyze the probability of a random person with the same alternative form of a gene (an allele) b. Examples - Identifying the suspect in a crime - Identifying an alleged father in a paternity case

17. Exit Ticket and Homework
Exit Ticket: What is DNA
Homework: Internet Search on the Romanov’s (p. 193)

18. Problem and Word of the Day
POD: How many chromosomes pairs does a human body cell have?
WotD: DNA Probe

19. Notes
11. Sources of DNA a. Biological evidence - examples include saliva, blood, skin, hair, seminal fluid b. Individual evidence - is capable of identifying a specific person c. Trace evidence - small amounts of DNA only d. Polymerase Chain Reaction (PCR) - technique generates multiple copies of DNA evidence

20. Notes
12. Collection and Preservation of DNA - Use disposable gloves and collection instruments - Avoid physical contact, talking, sneezing, and coughing in the evidence area - Air-dry evidence and put it into new paper bags or envelopes - Dry or freeze the evidence - Keep evidence cool and dry during transportation and storage

21. Notes
13. Preparing DNA Samples for Fingerprinting - DNA is mixed with special enzymes - Enzymes cut apart the DNA in specific places forming different sized fragments - DNA is separated within an agarose gel - An electric current is passed through the gel separating the fragments by size

22. Notes 13. Preparing DNA Samples for Fingerprinting (continued)
a. Extraction
Cells are isolated from biological evidence such as blood, saliva, urine, semen, and hair
The cells are disrupted to release the DNA from proteins and other cell components
The DNA can be extracted from the cell nucleus

23. Notes 13. Preparing DNA Samples for Fingerprinting (continued)
b. Amplification
VNTR analyses—polymerase chain reaction (PCR) can be used to amplify the DNA that contains the VNTRs
STR profiles—restriction enzymes are unnecessary; PCR allows the amplification of the strands with STR sequences
c. Electrophoresis
DNA samples are placed in gels through which electronic currents are passed
DNA fragments line up in bands along the length of each gel

24. Exit Ticket and Homework
Exit Ticket: Can identical twins have the same DNA?
Homework: Internet Search on the Romanov’s (p. 193)

25. Problem and Word of the Day
POD: If the sequence on one strand of DNA is:
GATCCTCATA
What is the sequence on the other strand?
WotD: Electrophoresis

26. Notes
14. Electrophoresis -An electrophoresis apparatus running five sample of DNA -Arrows show the movement of the negatively charged DNA fragments through the gel matrix

27. Notes 15. Probes DNA probes
- identify the unique sequences in a person’s DNA
- are made up of different synthetic sequences of DNA bases complimentary to the DNA strand
- bind to complimentary bases in the strand (see the fragmentary DNA bands above)
In most criminal cases, 6 to 8 probes are used

28. Notes
16. Analysis of DNA Fingerprints and Applications - Band and widths are significant in matching samples of DNA

29. Notes 16. Analysis of DNA Fingerprints and Applications (continued)
DNA fingerprinting can match crime scene DNA with a suspect
determine maternity, paternity, or match to another relative
eliminate a suspect
free a falsely imprisoned individual
identify human remains

30. Exit Ticket and Homework
Exit Ticket: Which child is adopted?
Homework: Internet Search on the Romanov’s (p. 193)

31. Problem and Word of the Day
POD: Which child is from the mother’s previous marriage?
WotD: Gene

32. Notes
17. Population Genetics and DNA Databases - is the study of variation in genes among a group of individuals - Proportions of the population that has a variation - Examples: blue eyes – low in Asian populations but high in European populations. - Examples: ABO blood types – 46% of European population is type O blood, while almost 100% of the South American population has type O blood.

34. Exit Ticket and Homework
Exit Ticket: List 4 things that DNA can be used to identify.
Homework: Connections – Draw DNA (p. 174)

35. Problem and Word of the Day
POD: When analyzing the DNA samples, how do you know which suspect is the culprit?
WotD: PCR

36. Activity Who are the parents? (pp. 187 – 188) MLA header Title
Objective
Data
Post lab questions

37. Exit Ticket and Homework
Exit Ticket: What is electrophoresis?
Homework: Finish Activity

38. Problem and Word of the Day
POD: What is the purpose of the agarose gel?
WotD: Restriction Enzyme

39. Activity Which Man is the Father? (pp. 189 – 190) MLA header Title
Objective
Data
Post lab questions

40. Exit Ticket and Homework
Exit Ticket: What does a restriction enzyme do to DNA?
Homework: Finish the Activity

41. Problem and Word of the Day
POD: What are the steps in DNA Fingerprinting?
WotD: STR

42. Activity The Break-In (pp. 191 – 192) MLA header Title Objective Data
Post lab questions

43. End of Chapter Assignment
Case Studies (pp. 170 – 171) and complete the Think Critically
Read Careers in Forensics (p. 172) and Summarize
End of Chapter Problems (p. 173)

44. Exit Ticket and Homework
Exit Ticket: Which fragments of DNA will move the farthest?
Homework: Finish the end of chapter problems

45. Problem and Word of the Day
POD: Summarize the Unit in 6 points.
WotD: VNTR

46. Summary
DNA contains the information needed for replication in a sequence of nitrogenous bases.
DNA analysis allows even a small sample of tissue to be identified with a single individual.
DNA contains, in non-coding regions called junk DNA, many repeated sequences that vary in number between individuals.
These differences between individuals can be used to produce a DNA fingerprint for an individual.

47. Summary
Polymerase chain reaction (PCR) for DNA amplification has largely eliminated the problem resulting from the tiny samples usually available.
DNA evidence must be collected carefully to avoid contamination with other DNA.
DNA analysis involves extraction, electrophoresis, and visualization.
DNA profiles are kept by police agencies in electronic databases.

48. Test, Exit Ticket, and Homework
Exit Ticket: Read the article and complete the guide
Homework: Finish the article and guide