The crime scene is in the food prep area of the Saddleback Cafeteria.  We have several samples taken from the crime scene.  The following is a list of the potential unknowns.  You have analyzed your unknown.  Your job is to determine from the various cells you have examined and a bit of detective work on the composition of the possible unknown that you have.  Please write a single paragraph explaining how you came to your conclusion.  Here are the possible unknowns:

plant root cell

plant stem cell

plant leaf cell

bacteria

Trypanosoma

Volvox

Paramecium

Ceratium

Frog skin

Human cheek cells

Elodea