Welcome to forensics!.pptx

1. Welcome to forensics!
Wednesday, 13 September 2023
Key words: Rigor mortis, decomposition
Starter: You have discovered a body…
What are the 3 main things we need to find out as forensic
scientists?

2. A2: What to expect
-4 topics in 2 papers (similar to AS)
- Unit 4 covers on the wild side (topic 5) immunity and forensics (topic
6)
- Unit 5 covers run for you life (topic 7) and grey matter (topic 8)
- Unit 6= coursework study carried out in the Isle of Wight/ school
grounds for those not attending the trip.
- Exams are synoptic…this means they will include some aspects of AS
within the papers. KEEP ALL YOUR NOTES FROM THIS YEAR!
- On a similar note we will study a scientific article (released in March
normally- it is different every year). This covers topics from both AS
and A2 and makes up 20 marks of your unit 6 paper.
- Again no January exams- both in the summer with coursework due
before then (dates will be confirmed nearer the time)
- More independent work needed as exam questions test application of
knowledge to new scenarios more than just recalling information like
AS.

3. The big picture: “How can we use
forensic techniques to solve a crime?”
Learning outcomes
To describe how a body can be identified.
To compare techniques for determining time of
death.
To evaluate what factors may make it difficult to
determine time of death.

4. Task 1
How can we determine who our dead person is?
They have no ID of any kind with them… what
forensics techniques could you use?
Answers on the post-it notes on your desk.
LO: To describe how a body can be identified.

5. Main techniques for identifying the body…
• Fingerprints
• Dental records
• DNA profiling (also known as genetic fingerprinting
or DNA fingerprinting)- the DNA is normally taken
from a cheek swab, blood smears at the scene, bone
marrow from the skeleton or sperm left after sexual
assault.
We will be looking at DNA profiling in another lesson

6. Determining time of death
Ways to determine how long the body has been dead
for…
1. Look at body temperature
2. Rigor mortis
3. Decomposition
4. Forensic entomology (using insects)- we won’t be
covering this one till next lesson.

7. Group task
• Produce a poster/mind map using the success criteria on
your given method of determining time of death.
• Try and reach the highest level you can and share out the
work load.
• You will need to use this to teach the class later…
Groups:
Rigor mortis: Georgie, Bryanna, Emma, Holly
Decomposition: Lucy D, Lucy P, Rhiannon, Nishat
Body temperature: Felicity, Megan, Alice, Laura, Charlotte

8. Summarise your findings
•For your forensic technique complete the
questions to summarise what you have
found out.
Be ready to share your work with the class.

9. Time to present your findings
Fill in your summaries whilst the other groups
are presenting.
If you have any questions note them down on
the post-it notes for the group to answer.

10. Plenary: Text book questions
Q6.10 Page 82: Measurement of body temperature to estimate
time of death is useful in cool and temperate climates. Why might
it be less useful in the tropics?
Q6.13 Page 84: Which of the following conditions will speed up
decomposition, and which will slow the process? Give reasons for
your answers. Conditions= a well-heated room, injuries to the body
surface, intense heat.
Page 67 green text book: Why is rigor mortis of limited use in
determining time of death?

11. Resources

12. Rigor mortis
Grade E: What is rigor mortis?
Grade D: How long after death does rigor
mortis usually set in?
Grade C: Why does rigor mortis occur?
Grade B: Explain the sequence of events that
occur during rigor mortis.
Grade A: Evaluate what factors can alter the
time taken for rigor mortis to set in.

13. Body temperature
Grade E: What is the normal human core body
temperature range?
Grade D: How is the body temperature of a corpse
measured?
Grade C/B: Draw a graph showing how body
temperature falls after death and explain it- what it
shows and any problems with using this method.
Grade A: What factors can affect post-mortem
cooling?

14. Decomposition
Grade E: Why do tissues start to break down after
death?
Grade D: Why are their often many anaerobic
bacteria on corpses?
Grade C/B: Explain the different signs of
decomposition.
Grade A: How can environmental conditions influence
the rate of decomposition?