Collecting Biological Evidence
By Joe LeFevre
Explore how to collect a fresh or dry blood specimen and prepare it for the crime lab.
This learning object shows how blood droplets are held together by a strong cohesive molecular force that produces surface tension in each drop and on the external force. Surface tension pulls the surface molecules of a liquid toward its interior, decreasing the surface area and causing the liquid to resist penetration.
Learners view videos of law enforcement and corrections officers describing their jobs and the opportunities in their fields. Because this object contains large video files, it is best viewed using a high band width connection. Low band widths will result in longer download time and video delays.