6th Grade · Science · Activity · shared by Luke Morgan
This 6th Grade Science activity helps students use microbiology to investigate a picnic illness, identifying the pathogen and tracing its source.
Case File: The Picnic Predicament
Yesterday, the Sunnyvale neighborhood held its annual summer picnic. It was a beautiful day filled with games, music, and a large potluck lunch. However, by this morning, several neighbors reported feeling very unwell. Local health investigators have been called in to determine what happened. Your task is to use your knowledge of microbiology to identify the specific cause of the illness and trace it back to the source.
Bacterial Reference Guide
To solve this case, you must first understand the two primary suspects. Use this reference table to compare the characteristics of these microorganisms.
Feature
Streptococcus thermophilus
Streptococcus pyogenes
Common Name
The Friendly Fermenter
The Pathogen
Microscopic Appearance
Chains of round cells
Chains of round cells
Primary Behavior
Performs fermentation; turns milk sugars into lactic acid to thicken food.
Attacks healthy cells in the throat to find energy to grow and spread.
Human Impact
Helps digestion; survives heat; used to make yogurt and snacks.
Causes strep throat, redness, swelling, and fever. Requires medicine.
Phase 1: Evidence Collection
Read the following clues collected from the picnic site and the local clinic. Use the evidence to fill in your investigation log.
Clue A: Patient Symptoms
Nurse Miller at the clinic reports that all ten sick neighbors have high fevers and complain of "stabbing" pain when they swallow. Looking at their throats, she noted extreme redness and white spots on the lining of the throat.
Clue B: Lab Results
A swab was taken from a patient's throat and viewed under a high-powered microscope. The technician observed long chains of round, sphere-shaped cells. No other unusual organisms were found in the sample.
Clue C: The Menu Log