Each group needs:

• 3 test tubes
• 2 eye droppers (for salt solution and hydrogen peroxide)
• Stopwatch or timer
• 2 small plastic or glass containers to hold the salt solution and hydrogen peroxide (such as baby food jars; no lids required)
• Living with Your Liver Worksheet, one per student
• (optional) 3 12-inch (.3 m) balloons (see Troubleshooting Tips section)

For the entire class to share:

• Liver solution: In a blender, blend 1/4 pound (113 g) of diced fresh beef liver with 13.5 fluid ounces (104 ml) water. Keep the liver solution refrigerated until 20 minutes before the activity. Do not allow the mixture to be kept at room temperature.
• 1 eye dropper (for dropping liver solution into test tubes)
• 2% salt solution: Mix 0.07 ounces (2 g) of salt with 6.8 fluid ounces (200 ml) of tap water
• 3% hydrogen peroxide (H₂O₂; available at pharmacy or grocery store)
• (optional) Masking tape and markers (to label small jars and test tubes)