Advanced Environmental and Earth Sciences Teacher Guide

(PS-2979)

Teacher manual for Advanced Environmental and Earth Sciences labs. Has both the printed version and a flash drive with teacher tips, a PDF of teacher version and editable Word student version.

Toxicology Using Yeast

Lab Summary

Use a carbon dioxide gas sensor and a pH sensor to evaluate the role of pH in toxicity and the role of cell culture in toxicology studies.

Theory

Students demonstrate how yeast cells can serve as simple models to assess chemical hazards. They also:

  • Evaluate the role of pH in toxicity.
  • Evaluate the role of cell culture in toxicology studies.

 

Method

Students determine the relative toxicity of half-strength bleach and full-strength vinegar using a yeast cell culture system. They gain experience completing the following procedures:

  • Conducting toxicology studies of yeast cell cultures in a closed system, measuring the carbon dioxide gas level as the indicator of toxicity, and correlating pH with toxicity.
  • Extrapolating the median effective dose (ED50) for half-strength bleach and full-strength vinegar from experimental data.

Sensors / Equipment Used:

PASPORT Carbon Dioxide Gas Sensor

(PS-2110)

The PASPORT Carbon Dioxide Gas Sensor measures carbon dioxide concentration CO2 (parts per million) in gases such as air. Ideal for studies of photosynthesis, respiration, fermentation and more.

Advanced Water Quality Sensor

(PS-2230)

MultiMeasure sensor that incorporates pH, conductivity, temperature, and the optical dissolved oxygen probe.

EcoChamber

(ME-6667)

A single acrylic chamber designed to integrate sensors for controlled-environment experiments such as fermentation and plant or cricket respiration.

Materials Used:

Beaker, 100-mL (for vinegar) 
Beaker, glass, 2-L 
Erlenmeyer flask, 125-mL 
Graduated cylinder, 1-L or 500-mL 
Graduated cylinder, 25-mL or 10-mL
Household bleach, half-strength - 50 mL
Magnetic stir plate and stir bar 
Rapid-rise activated baker's yeast (7-g packet)
Rubber stopper for Erlenmeyer flask 
Stirring rod 
Sugar - 100 g
Water - 1 L
White vinegar - 50 mL

The Associated Bundle:

Advanced Environmental and Earth Science Standard Sensor Bundle

(PS-2916A)

Standard bundle for Advanced Environmental and Earth Sciences Teacher Guide,

Interface Required

This experiment may require software and an interface for data collection.