Name Date Due: Worth Points 9/9. 1. Physical Evidence is. 2. The examination of physical evidence is done for and

Transcription

1 Name Date Due: Worth Points 9/9 Physical Evidence Review 1. Physical Evidence is 2. The examination of physical evidence is done for and 3. -to determine the physical and chemical properties of a substance with certainty 4. -to compare a suspect specimen and a standard and /or reference specimen (Exemplar). 5. When Collecting Trace Evidence, a paper act as containers to hold trace evidence. 6. Trace Evidence is 7. Trace evidence is lifted from surfaces using the. 8. Fibers- 9. A filament 10. Fibers are identify using what two laboratory procedures: 1. ) 2.) 11. A length of fiber can be individualized to a particular garment of clothing, for example the blue sweater worn. 12. Fibers are considered class evidence. When do they become individual evidence?. Example: 13. How can the Locard Exchange Principle explain how trace evidence can link suspects to victims and crime scenes? 14. What are the 2 main types of fibers? and 15. Natural fibers are. Examples are and from plants and from animals Which natural fiber is the most common? 16. was the first manmade fiber, it was derived from (wood) & chemicals.

2 17. Other manmade fibers we studied in the lab would be,, and 18. is made from Glass fibers that are pulled and aligned to form mats, they are used to reinforce plastics Ex. Used in and 19. The hair layer called the cuticle is 20. The hair layer called the Cortex is These cells contain the that give hair its. 21. The hair layer called the Medulla is. 22. Medulla is important because it contains DNA which can be used to individualize the hair. 23. The draw and identify the four types of human medulla classification are 24. Why do humans still have hair? What is the Medulla Ratio? = 26. Calculate: Hair evidence has a medulla diameter of 75u and a hair diameter of 150u, what is the medulla ratio of the hair? 27. From the calculation in #26,is the hair from a human or an animal? Explain. 28. Synthetic hair, like the hair found in wigs would have which characteristics missing or absent?,, and

3 29. What are the 3 types of scale patterns, sketch them here and give animal examples: 1.) Human 2.) - cats 3.) rabbit 30. What are the 3 ways that human hair can be distinguished from animal hair? 1.) 1.) 2.) 3.) 31. What are the 3 types of scale patterns, sketch them here and give animal examples: 1.) 2.) 3.) 4.) 32. Define Density: 33. What is the equation for calculating Density? D = 34. Calculate: A glass sample has a mass of grams and volume of 6.0 ml, what would be its density? 35. Glass is considered class evidence, but glass from various have slightly different due to the presence of. 36. Glass has differing metals such as :,,, and. These metals give the glass a unique. 37. The composition of glass is a hard brittle substance made of mostly ( ), lime, soda, and oxides of. 38. Auto headlight (heat resistant) glass contain. 39. Safety auto glass is which is made strong by rapid heating and cooling process that introduces stress to the glass.

4 40. How does tempered glass act as a safety feature in autos? safety glass is very strong because it is made of 2 layers of glass sandwiching a layer of plastic. It is used in the (safety feature) keeps the passengers. 42. How would a Forensic Geologist describe soil? 2.Included are 43. Why is Soil evidence is dried to 100 o C? 44. Soil colors come from their mineral content: grey or black is from (symbol= ) green or orange is from Copper (symbol = ) and pink from Potassium ( symbol = ). 45. Soils are made of 3 particles types that give it TEXTURE: 1.) (largest particles) 2.) (medium) 3.) (small) 46. Soil Chemical Properties: ph- refers to. ph Scale goes from (acid) to (base) with a ph of = neutral Less than 7= greater than 7 = 47. What is the Munsell Color System? 48.In using the Munsell Color System, what are chips? 49.Why is a microscope the best scientific instrument to observe trace evidence?

5 50.Is glass considered to be class or individual evidence? Explain your answer. 51.Describe 2 methods for collecting trace evidence such as fibers. 1.) 2.)