Lab Results:
The Relationship Between
Diffusion and Cell Size
The agar/phenolphthalein block
before carving…
• Phenolphthalein is an
acid/ base indicator.
It turns pink in the
presence of a base
and is clear and
colorless in acidic
solutions.
• NaOH was added to
the block in addition
to the indicator to help
turn the block pink.
The “cells”…
• The main block was
carved into three
smaller cubes which
represent different
sized cells.
Soaking the blocks (“cells”)…
• The blocks were
soaked in a dilute HCl
acid solution for about
10 minutes.
• The images show the
results emerging
during the soaking
time.
The results….
• The blocks were
removed from the
acid solution after 10
minutes, blotted dry,
cut open, and the
depth of diffusion was
measured…