#3

Question 1

Identify the average volume of blood found in an adult human.

Answer 1

~5 liters of blood

Question 2

Describe what happens when 30% of an adult’s blood volume is lost.

Answer 2

Unconscious

Question 3

Describe what happens when 40% of an adult’s blood volume is lost.

Answer 3

Death

Question 4

Explain why examination of only external blood may not be the most accurate measure of blood
loss.

Answer 4

You can also have blood loss internally

You have to use the possibility of internally and externally too.

Question 5

Differentiate the color of arterial and venous blood.

Answer 5

Arterial blood is brighter (more O2) than Venus blood

Question 6

Explain why after about 3 minutes you can’t distinguish blood’s origin.

Answer 6

Blood darkens and starts to clot in 3 minutes therefore you can’t tell it is arterial or venous

Question 7

List the three main categories of bloodstain patterns.

Answer 7

Passive Stains
Spatter Stains
Altered Stains

Question 8

List the four types of Passive Stains.

Answer 8

Drops
Flows
Transfers
Large volume

Question 9

Drops are caused by

Answer 9

Gravity

Question 10

Height affects the

Answer 10

Pattern

Question 11

From a short distance , the drops are

Answer 11

More uniform

Question 12

From a greater height , the drops are

Answer 12

More sunburst pattern

Question 13

If the drops land on wet blood,

Answer 13

Satellite pattern

Question 14

The surface affects the what as well

Answer 14

Pattern

Question 15

Drops may provide a

Answer 15

Direction of movement

Question 16

Flows are a different form what

Answer 16

They are still passive Stains and they form small streams (rivers), creaks of blood

Question 17

Forms are used to

Answer 17

Determine orientation of body at time of attack

Question 18

If your standing, how will the flow be

Answer 18

Blood will flow straight down

Question 19

If your laying down, how will the flow be

Answer 19

Blood will veer to the side angled towards the floor

Question 20

If the body is moved, how will the flow be

Answer 20

Multiple flow paths may be seen

Question 21

Clothing may affect/change

Answer 21

Flow patterns

Question 22

Transfers are

Answer 22

Wet blood transferred to an object

Question 23

Examples of transfers

Answer 23

Bloody hands leaving prints on door

Blood on shoes leaves trail

Question 24

What are large volume

Answer 24

Pool of blood under victim

Question 25

What diseases cause victims to cough or vomit large amounts of blood

Answer 25

Tuberculosis(TB) | Ebola

Question 26

List the three causes of Spatter Stains.

Answer 26

Secondary mechanisms Impact mechanisms Projection mechanisms

Question 27

Spatter Stains are based by

Answer 27

Cause

Question 28

Secondary mechanisms

Answer 28

Spatter secondary to cause of initial wound Ex: blood drips on wet blood

Question 29

What are impact wounds

Answer 29

Wounds caused by some sort of impact Ex: gunshot. Blunt/Sharp object, industrial tools

Question 30

All mechanisms cause similar pattern

Answer 30

^

Question 31

Gunshots are caused by what

Answer 31

High pressure air

Question 32

Gunshots often produce

Answer 32

Back spatter (towards firearm) & forward spatter (in direction of projectile) May include fragements of flesh & bone

Question 33

Suicide victims might have

Answer 33

Blood spatter & gunshot residue on hand/arm/clothing An homicide victim will not

Question 34

Back spatter does not always happen so

Answer 34

It is not consistent

Question 35

As speed of impact increases,

Answer 35

Droplet size decreases | It can be as small as 1mm or less in diameter

Question 36

Understand that spatter is not uniform, and therefore not a definitive forensics test.

Answer 36

^^

Question 37

Explain why prolonged beatings produce more blood than brief beatings.

Answer 37

Prolonged beatings open wounds larger which makes more volume of blood spatter

Question 38

Faster impacts produce

Answer 38

Smaller drops

Question 39

What is produced where objects, or people, are Located during a beating

Answer 39

Voids

Question 40

List the three types of Projection Mechanisms.

Answer 40

Spurt pattern Coughing and sneezing Cast off Stains

Question 41

Spurt patters are arteries that have

Answer 41

Hugh pressure (from force of heart contraction)

Question 42

Arteries continue to spurt as

Answer 42

The hearts beats

Question 43

Artieries follow a characteristic pattern called a

Answer 43

Arterial spurt stain

Question 44

Spurt patter is also veins which have

Answer 44

Low pressure

Question 45

Veins flow

Answer 45

Downhill and does not spurt

Question 46

Varicose veins do have

Answer 46

Greater pressure

Question 47

Varicose veins are caused

Answer 47

When valves stop working and blood pools in dependent areas p(legs) The pattern will be on the floor or lower veritical surface

Question 48

Coughing and sneezing creates

Answer 48

A stream of fast moving air | Contains small droplets and aerosal of microscope droplets <100um in diamtee

Question 49

Wounds to chest, mouth or nose results in

Answer 49

blood droplets of similar size Drops >100um don't travel far Drops <100um can remain airborne for Long periods and travel far

Question 50

Stains that contain mucous will

Answer 50

Help identify origin

Question 51

Small droplets may form when

Answer 51

Breathing into a pool of blood

Question 52

Cast off Stains are formed when

Answer 52

Thrown from weapon or limb as it moves | Ex: knife being pulled out will produce spatter

Question 53

Axes and heaving objects are usually wielded downward, so

Answer 53

Spatter is in ceiling

Question 54

Weapons with lots of blood leave Stains from

Answer 54

Upward and downward stroke In cast of stain

Question 55

Stains in arc are more circular above assilants head and more elliptical and longer at ends of strokes

Answer 55

^^ in cast off Stains

Question 56

Altered stains are

Answer 56

Any change to initial blood stain

Question 57

What causes altered stains

Answer 57

``` Blood falls on other blood Body falls in blood stain Diffuses through clothing Trying to clean it up Insect movement Body movement ```

Question 58

Altered stains will make the Clots will

Answer 58

Be in drag pattern if body is moved hrs after death | - no clots - Body moved soon after death

Question 59

Smears & smudges are from

Answer 59

Trying to clean up blood and from moving a bleeding body

Question 60

A smear indicated

Answer 60

Direction of movement Begins as a series of drops Becomes ragged along own edge -showing direction

Question 61

Define Toxicology.

Answer 61

Chemicals in the blood

Question 62

Toxicological analysis of blood

Answer 62

Testing for chemicals in the blood

Question 63

What are the variables for toxicological analysis of blood

Answer 63

1) Blood settles to dependent regions. - drugs redistribute and concentrations may change - no census on how many regions to test 2) all drugs behave differently 3) environmental & PMI affect results 4) drugs users build up a tolerances for drug concentration will be greater, but investigators doesn't know tolerance 5) microbial fermentation forms ethanol; false positive for alcohol intake prior to death