Case of the “Grass-Stained” Bandits

There was little doubt that someone had eaten nearly a third of the apple pie set out on the kitchen counter. Bryn was sure that no one had had come through the kitchen door since she had taken the pie out of the oven.

“How did they do it?” Bryn wondered.

She surveyed the counter and noted an open window with crushed ferns in the window box outside. “Oh, an outside job…” she concluded.

Just then, the likely suspects, brothers Emmet and Liam ran into the kitchen.

When she asked them about the missing pie, both acted and declared their innocence.

“Hmmm!” she thought while observing green stains on their shirts and pants.

Stains from t-shirts

When she asked how the stains got there, Liam explained that they might be from a soccer game.

Emmet agreed and explained that the grass was still wet from the automatic sprinkler so there had been quite a bit of slipping and sliding.

Remembering her lab on photosynthesis, Bryn smiled. “Follow me,” she said and went into her room.

She reached up to get nail polish remover and rubbing alcohol from the shelf.

Chromatograms:

Emmet’s stains Liam’s stains

Accessory pigments - evident when chlorophyll absent

Plants, algae, cyanobacteria

Plants, green algae

Chromatograph, Chlorophyll Resources:

1.http://www.mysciencebox.org/plantpigment2. http://botit.botany.wisc.edu/images/130/Photosynthesis/Chromatogram_small.html3. http://www.carlinvilleschools.net/linke/Biology/bio.htm4. http://www.baskin-jones.com/student_work-page5.htm

1.http://www.mysciencebox.org/plantpigment2. http://botit.botany.wisc.edu/images/130/Photosynthesis/Chromatogram_small.html3. http://www.carlinvilleschools.net/linke/Biology/bio.htm4. http://www.baskin-jones.com/student_work-page5.htm