1. Basic Fingerprint Patterns
Aim: How are fingerprints classified?
Do Now: take a handout
HW: Finish Worksheet

2. Medical Mystery: People w/ No Prints
Cheryl Maynard has a rare genetic disorder called DPR, or dermatopathia pigmentosa reticularis, and she's not only missing fingerprints -- she's also missing those unique marks on her toes, in addition to being unable to sweat. The condition is passed down through the female side of the family. People that suffer from DPR can also have extremely thin hair, brittle, ridged nails and mottled skin. DPR is so rare that the Maynards were the only family in the world known to carry the genetic defect. How is this condition possible? The ridges on our fingers and toes start forming in utero at about 11 weeks. However, if certain genes mutate, the body never creates the signals that form the prints -- resulting in the Maynard family condition.

3. What is a delta?

4. LOOP Comes in and curves Goes back out same side
Enters and Exits on same side 4

5. Loops Loops must have one delta Delta on left = Ulnar
Delta on Right = Radial
Ulnar Loop
Loop opens toward little finger.
Radial Loop
Loop opens toward thumb.
Delta
NOTE: On the left hand, delta would be on the opposite side

6. ARCH
Enter on one side
Rises
Falls
Goes out on the other side 6

7. Arches Arches are the simplest type of fingerprints.
No deltas are present.
Tented Arches
Sharp rise
Spike or “tent”
Plain Arch
Smooth rise

8. Ridges rise smoothly in center in a wave-like pattern
Plain Arch
Ridges rise smoothly in center in a wave-like pattern
Plain Arch
Tented Arch
Ridges in the center thrust upward to give an appearance similar to a tent.
Sharp rise
Tented Arch 8

9. WHORL
Ridge recurves around 2 deltas
Looks like a circle 9

10. Plain Whorl One ridge makes a complete circle
Line between deltas touches or runs through circle

11. the line between the deltas does not touch the circle
Central Pocket Whorl
the line between the deltas does not touch the circle

12. Double Loop Whorl two loops combined into one fingerprint
Looks like an “s” 12

13. Accidental Any pattern that was not yet mentioned
Any combination of patterns mentioned
Example: loop with a plain whorl

14. Identify each fingerprint pattern.? A B
Right Hand
Left Hand
Answer Key: A - Plain Whorl, B – Double Loop Whorl, C – Radial Loop, D – Tented Arch, E – Plain Arch C
Right Hand E D
Right Hand
Left Hand

15. A - Plain Whorl, B – Double Loop Whorl, C – Radial Loop, D – Tented Arch, E – Plain Arch

16. It’s time to make some prints!
Textbook pg 77-78
Avoid Partial Prints
GOOD PRINT Get as much of the top part of your finger as possible!

17. Directions
1st – Roll the “pad” portion of your thumb over the ink pad from the left side of your thumb to the right. You do not have to push down really hard!
2nd – Roll the “pad” portion of your thumb from the left side of your thumb to the right in the correct box on your paper to make a thumbprint.
3rd – Continue this process to make a fingerprint of all ten fingers on the “My Prints” worksheet.
4th –Use your notes and a magnifying lens to help you figure out what type of pattern is found in each of your fingerprints. Label each one with the pattern’s name.