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Fingerprint Lab
Fingerprints• Fingerprints are an impression of the
lines on the inner surface of the thumb and fingers.
• Patterns are made by tiny ridges on the skin.
• The ridges on our fingertips help us grip objects.
• When we touch an object, the oil and perspiration (sweat) on our skin leaves behind a latent (potential) fingerprint.
Fingerprints• Investigators dust latent fingerprints
with a fine powder to make the patterns visible and then lift the fingerprints with sticky paper.
• Fingerprints are permanent details that are created before you are born.
• No two fingerprints are the same, not even on the same person or on identical twins.
Lab Write Up• Title: Fingerprint Lab
•Problem: Which is the most common type of fingerprint in our class?
`
3 Types of FingerprintsWhorls
30-35 % of people
Arches5 % of people
Loops60-65% of
people
ResearchWhat do you know about
fingerprints?
Have you ever checked your fingerprints? Tell me your experience with fingerprints.
HypothesisHypothesis: If… then…because…
If each person finds their fingerprint type, then the _________ (loop whorl, arch) fingerprint will be the most common because__________
UNDERLINE the words IF THEN and BECAUSE in your hypothesis
Materials• 1 piece of scratch paper• 1 pencil• 1 magnifying glass• 1 roll of clear tape
VariablesIndependent Variable (the one
thing you change) – the type of fingerprint
Dependent Variable (the one thing
you measure) – the number of fingerprints
Procedure1. Rub the pencil on the scratch paper until there is a
smudge of graphite the size of your fingertip.2. Select which hand you will take fingerprints from.3. Beginning with your thumb. Rub it on the smudge
until your thumb is covered in graphite.4. Place a small piece of tape over your thumbprint
and press down gently.5. Carefully remove the tape and stick it in the
appropriate square on your data table.6. Repeat the process for the other 4 fingers of your
hand. 7. Look at your fingerprints and identify which type of
fingerprint you have.8. Record the class tallies for each type of fingerprint
and then find the total
Data
Loop
TABLE DATA
`
Identify your type of fingerprint
Graph
Type 0
2
4
6
8
10
12
14
Fingerprints
LoopWhorlArch
Type of Finger Print
Nu
mb
er
of
Fin
ger
Pri
nts
After you make your graphAnswer the following
questions using COMPLETE SENTENCES.
1. What percent of your class had arches? Whorls? Loops? Find the percentage by dividing the number of each type of fingerprint by the total number of fingerprints and then multiplying by 100Ex: 5 whorls/20 total fingerprints = .25 .25 x100 = 25%
2. What is the most common type of fingerprint in your class?
3. Was your hypothesis supported? Why or why not?
4. Make a Fingerprint Animal
When you are finshed
Try making some fingerprint
animals
Data
Tally Marks and then write the
total
Loop
/Group Data