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Essay Instructions: Experiment : Bloodstain Geometry Experiment
The purpose of this lab is to help to become familiar with the basic geometric shapes and patterns
formed by droplets of blood when they impact various target surfaces at a 90° angle. You should also
learn the about the effects that various surface textures will have on the geometry of the blood droplets as
well as how you articulate your recognition, documentation, and interpretation of the bloodstain evidence.
Finally, you will observe what blood may look like after traces of it are removed using a presumptive blood
test.
You will document your findings, sketch the appearance of the stains, and answer some questions about
the experiment

Artificial Blood Preparation
There are three variations for creating your artificial blood. Choose the method that works best for you.
1. Use 4 oz of evaporated milk, 2-3 tablespoons of tomato paste, and red food dye. Mix to the
viscosity of blood and use water to thin as necessary. This artificial blood mixture should be
freshly made; it is only good for a few days. Store in refrigerator if necessary.
2. Use 4 oz of Carnation® dry milk, red food dye, and water. Mix to the viscosity of blood.
3. Use 4 oz of white corn syrup and red food dye. Mix to the appearance of blood.

Equipment and Supplies
1. Plastic dropping pipettes
2. A few pairs of gloves
3. A face mask (as a precaution against artificial blood, since it can be messy)
4. L-Scale labels to measure and document your stains


Supplies from your local craft or discount department store:
1. A 12-inch square piece of cardboard (or something of a like texture)
2. A 12-inch square piece of plywood (or something of a like texture)
3. A 12-inch piece of ?inch thick smooth, clear piece of acrylic (or something of a like texture)
4. Paper towels
5. Tape measure
6. Ruler

a. If you want to experiment on an additional surface, you can also drop blood onto a floor tile,
carpet, or piece of clothing

Directions:
1. Drop one drop of artificial blood straight downward onto each surface (cardboard, plywood,
acrylic, piece of paper towel) texture being tested from the height of 1 inch, 2 inches, 36 inches,
and 72 inches.
2. The test surfaces should be placed flat on the floor (not a carpeted floor) and the pipette should
be held perpendicular to the surface when the blood drops are released.
3. Draw a well-mixed quantity of the artificial blood into the pipette and wipe off any excess blood
from the outside of the pipette with another paper towel. Be careful not to include any air bubbles
with the blood.
4. Make your observations while the stains are wet and after the stains have thoroughly dried.
5. Once stains are dry and properly documented, attempt to clean up the dried blood using a slightly
damp towel.
6. Utilizing the alka selzer Tablets to make a presumptive test solution, you will visualize the cleaned
up blood, photographing your results and documenting your observations. Note: To make the
presumptive test solution, simply place both tablets into the spray bottle and add four ounces (4
oz.) of water. Shake thoroughly until tablets are completely dissolved. Dispose of empty
packaging safely.

Report Observations and Documentation

1. Sketch the appearance of your blood drops at each height. Either photograph or scan your sketch
for submission.

2. For each surface texture being examined, make the following observations and record your
answers:
a. Describe the texture of the surface: hard/soft; smooth/rough; porous or nonporous
b. Describe the edge characteristics of the resulting stains
c. Measure the diameter of each drop (in millimeters)
d. Describe the extent of peripheral satellite spatter
e. Discuss what effect changing the dropping height had on the resulting stains
f. Document your observations of the effect of alka selzer on the cleaned up blood; was it what
you expected? Why or why not? Did you have difficulty applying the solution?
g. If possible, experiment with other surface textures (as previously described) and document
your results

Essay Instructions: Experiment Guidelines: Is yawning contagious (speaking of human beings). Create an research paper on whether it is contagious or not and why.

Label each section clearly: Introduction, Materials and Methods, Results, and Discussion

Introduction
In general, your introduction should set up your study system: why are you performing your study? Why are you interested in the subject? What is its significance? To think of it in another way, plead the significance of your study as if you were applying for money; why should someone care enough in your project to give their precious money to fund it? All of these points should be addressed in a flowing manner, not in this particular order.

Materials and Methods
Pretty straightforward.

Results
Your results section should contain both a figure/table, as well as written results. This may seem repetitive, but the figures are meant to be a graphical representation of your results, and support what your text says.

must include at least one figure or table in your results section. *Describe what your figure is showing*”

Discussion
Your discussion section is the interpretation of your results: why did you see the results you saw? Were there other factors/variables that could have affected your experiment and results? Relate your results back to your introduction and how you set up your project.

Source citation

Essay Instructions: Experiment #2: How do you identify yourself? For this experiment, dress in the opposite mode of style

of the way you identify yourself. For example, if you mainly identify yourself as a man, dress up like a

?feminine woman.? Or if you identify yourself primarily as a student, dress up like a professional

employee or a homeless person. Walk around or go about your daily business for 1-2 hours. Make

observations of how you feel, how others treat you, how you act, etc. Write up your report using

relevant sociological theories and concepts

NOTES:

1. This written assignment should be 2 pages, double spaced with 1.25-inch margins.



USEFUL SUGGESTIONS:

It is good to have:

1-2 paragraphs explaining/ describing what you did;

**1-2 paragraphs discussing theory (analyze the theory, and describe the relationship between the paper and the theory, please to read the file, it is theory)

**2-3 paragraphs explaining what you saw/ felt and analyzing using theory.

(** means important)

Essay Instructions: Resource: Research Methods in Psychology

Prepare written responses to the following questions. The response to each question should be at least 250 words in length.



· What are the similarities between descriptive and inferential statistics? What are the differences? When should you use descriptive and inferential statistics?

· What are the similarities between single-case and small-N research designs? What are the differences? When should you use single-case and small-N research designs?

· What are true experiments? How are threats to internal validity controlled by true experiments? How are they different from experimental designs?

· What are quasi-experimental designs? Why are they important? How are they different from experimental designs?



Format your paper consistent with APA guidelines.