1. Objective: (SAME AS YESTERDAY) SWBAT use the evidence of livor mortis, rigor mortis, and algor mortis to calculate the approximate time of death Do Now: 1.Describe the causes of rigor mortis. 2.Define livor and algor mortis 3.How can these be used to calculate time of death?

2. Simple Terms What?Why ?Factors that will affect it Rigor Livor Algor

3. Mortis Mortis refers to death Mortis refers to death Rigor Mortis - stiff Rigor Mortis - stiff Livor Mortis- blueish color Livor Mortis- blueish color Algor Mortis- coldness Algor Mortis- coldness

4. Rigor Mortis

5. Skeletal muscles partially contract Skeletal muscles partially contract Joints stiffen, lock in place Joints stiffen, lock in place Beginning about 2 hours after death Beginning about 2 hours after death Lasting about 30 hours Lasting about 30 hours

6. Simple Term (s) What?Why ?Factors that will affect it Rigor Livor Algor

7. Chemistry of Rigor Mortis Calcium -> ATP Calcium -> ATP http://www.youtube.com/watch?v=CepeY Fvqmk4 http://www.youtube.com/watch?v=CepeY Fvqmk4 http://www.youtube.com/watch?v=CepeY Fvqmk4 http://www.youtube.com/watch?v=CepeY Fvqmk4 1:40 1:40 End of rigor mortis End of rigor mortis

8. End of Rigor Mortis Autolysis Autolysis decomposition decomposition digestive enzymes digestive enzymes Rupture and release fluids Rupture and release fluids The muscles relax when the body starts to decompose and the cells begin to break down The muscles relax when the body starts to decompose and the cells begin to break down

9. RED LIGHT!!!!! What causes rigor mortis? What causes rigor mortis? STOP! Hold Up! Whoa There! Run That Back

10. Ca and ATP Ratchet the Fibers

11. 30-15 30 seconds to explain 30 seconds to explain 15 seconds to ask questions 15 seconds to ask questions Switch Switch

12. Why is this useful Time Time Position Position Location Location

13. Livor Mortis Heart stops beating which had been mixing blood Heart stops beating which had been mixing blood Red blood cells are denser so they sink Red blood cells are denser so they sink Maroon to blue color develops at lowest points Maroon to blue color develops at lowest points Visible 30 minutes 12 hours after death Visible 30 minutes 12 hours after death Tells you if the body was moved. Tells you if the body was moved.

14. Livor Mortis Pressure prevents pooling Pressure prevents pooling

15. Livor Mortis

16. After death cells release enzyme that prevents clotting After death cells release enzyme that prevents clotting Blood in body stays liquid after death Blood in body stays liquid after death

17. Algor Mortis Rate of cooling of body after death Rate of cooling of body after death –1.5 ° F per hour under “normal conditions”  0.78 Degrees Celsius

18. Algor Mortis Clothing Clothing –Insulates body from heat loss Obesity Obesity –Fat insulates, temperature falls more slowly Ratio of surface area to volume Ratio of surface area to volume –Children, thin people cool faster In water? In water? –Cooling is faster since water is a better conductor of heat than air

19. A man is found on the side of the road. His body temperature is 32° C. How long has this man been dead? A man is found on the side of the road. His body temperature is 32° C. How long has this man been dead? A woman is found dead. Her body temperature is 25° C. How long has this woman been dead? A woman is found dead. Her body temperature is 25° C. How long has this woman been dead?

20. Exit Ticket Be specific 1.How can rigor mortis be used to calculate death? How can algor mortis be used to calculate death? How can livor mortis be used to calculate death? Show your work 2. How long has a victim been dead, if she was found with a body temperature of 24 degrees Celsius? (R. more)