1. Shrimp cocktail
What tools do scientist use to assess the toxicity of different compounds?

2. Teaching Standards Environmental science standards Biology standards
Recognize that humans are part of the global ecosystem and evaluate the effects of human activities on ecosystems
Biology standards
Assess how human activities such as pesticide use influence and modify the environment
Relate animal adaptations, including behaviors, to the ability to survive stressful environmental conditions

3. Bioassays What is a bioassay? What is a bioindicator?
What characteristics make a good bioindicator species?
Sensitivity
Representative of the system you are interested in?

4. Ghost shrimp Crustaceans Scavengers
Easily observable under dissecting microscope
Nearly translucent
Sensitive to environmental changes

5. Acute vs Chronic effect Sublethal effects
Once we choose an indicator species, how do we measure the effects of a chemical?
Acute vs Chronic effect
Sublethal effects
Behavior
Heart rate-stimulants vs. depressants
Lethal effects
LD50
Dose/concentration is important
Sublethal effects
Fig 1. Effect of two insecticides on insect survival

6. Activity 1 Sublethal effects of chemicals on ghost shrimp
Record baseline heart rate
Add a single drop of each solution and measure change in heart rate
Ethanol, sugar solution, hot and cold water

7. Activity 1 Questions Which solutions showed an increase in heart rate?
Which solutions showed a decrease in heart rate?
Which solutions would you classify as stimulants? Depressants?