Learning Intentions:

We are learning to.... understand how fingerprints are used in the identification of possible suspects.

So that we can... gain further knowledge about fingerprints and their different types.

We will be able to.... watch the video clip and view your own fingerprints.

Identical twins will have the same DNA profile but different pattern of friction ridges.  To be used as evidence a suspect’s fingerprint must match the scene of the crime print in 10 places.  However, this only proves they were at the scene, not that they committed the crime.  Other evidence is also needed.

PRACTICAL ACTIVITY:  MAKING FINGERPRINTS

Equipment:  Inkpads

             Magnifying glass

 Method:

·        With the ink pad on the edge of the bench gently roll your left thumb over the inkpad

·        Without pressing too hard gently roll your thumb over the corresponding space on the worksheet provided (see below)

·        Repeat for all fingers on both hands

·        Be careful not to get ink over the table

·        Wash your hands thoroughly with soap

·        Use a magnifying glass to examine the prints

We are learning to.... lift fingerprints from different surfaces

So that we can... gain an understanding about the process and it's difficulties

We will be able to.... dust and then lift fingerprints

PRACTICAL ACTIVITY: DUSTING FOR PRINTS

Equipment:   

             Talcum powder

             Carbon powder

             Brush

             Sticky tape

                black paper, white paper

Method:  Follow the demonstration of how to lift prints with talc and carbon powder from a glass slide.

Discussion:

1.    Which of the surfaces gave the clearest prints using talcum powder?

2.   Which of the surfaces gave the clearest prints using carbon powder?

3.   Which surfaces gave poor prints using both surfaces?

4.   Do you think police could use powders to get prints off clothes? How do they do this? (Google)

5.   Salt and sugar are also white powders. Could they be used to collect prints?

6.   When would the police use carbon powder to collect prints?