Presentation is loading. Please wait.

Presentation is loading. Please wait.

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.

Similar presentations


Presentation on theme: "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."— Presentation transcript:

1

2 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.

3 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.

4 Title: Fingerprint Lab Problem: Which is the most common type of fingerprint in our class?

5 ` Whorls 30-35 % of people Arches 5 % of people Loops 60-65% of people

6 What do you know about fingerprints? Have you ever checked your fingerprints? Tell me your experience with fingerprints.

7 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

8 1 piece of scratch paper 1 pencil 1 magnifying glass 1 roll of clear tape

9 Independent Variable (the one thing you change) – the type of fingerprint Dependent Variable (the one thing you measure) – the number of fingerprints

10 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

11 Loop TABLE DATA

12 `

13

14 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

15

16 Loop /Group Data


Download ppt "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."

Similar presentations


Ads by Google