• 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.
• 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.
• Title: Fingerprint Lab
• Problem: Which is the
most common type of
fingerprint in our class?
Loops
60-65% of
people
Whorls
Arches
30-35 % of
people
5 % of people
`
What do you know about fingerprints?
Have you ever checked your
fingerprints? Tell me your experience
with fingerprints.
Hypothesis: 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
•1
•1
•1
•1
piece of scratch paper
pencil
magnifying glass
roll of clear tape
Independent Variable (the one thing you
change) – the type of fingerprint
Dependent Variable (the one thing you
measure) – the number of fingerprints
1. 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
Loop
TABLE DATA
`
Number of Finger Prints
Fingerprints
14
12
10
8
Loop
6
Whorl
4
Arch
2
0
Type
Type of Finger Print
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 100
Ex: 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
Loop
/Group Data