Standard III: Students will understand the structure
of cells and organisms.
Objective 1: Observe and describe cellular structures and functions.
Indicator e: Describe that many of the basic functions of organisms
are carried out within cells (e.g., extract energy from food, remove waste).
Intended Learning Outcomes:
1 D. Select the appropriate instrument; measure, calculate and
record in metric units, length, volume, temperature and weight, to the
accuracy of instruments used.
1 E. When given a problem, plan and conduct experiments in which
› Form research questions and hypotheses.
› Predict results of investigations based upon prior data.
› Identify variables.
› Plan procedures to control independent variable(s).
› Collect data on the dependent variable(s).
› Select appropriate format (e.g., graph, chart, diagram) to summarize
› Analyze data and construct reasonable conclusions.
› Prepare written and oral reports of their investigation.
3 A. Provide relevant data to support their inferences and conclusions.
4 B. Use precise scientific language in oral and written communication.
4 C. Solve problems appropriate to grade level by applying scientific
principles and procedures.
Background: Students should have general knowledge of the functions
of organelles within the cell. They should understand that yeast extracts
the energy in sugar and produces Carbon dioxide (CO2) waste.
Time Required: 45 minutes
Summary: Have you ever baked bread? What is it that makes the bread
rise? Its the yeast. But what is it that makes the yeast grow? Its
the sugar. Yeast extracts the energy from the sugar to make it grow. In
the process, it produces Carbon dioxide waste. It is the Carbon dioxide
waste that makes the bread rise or have holes in it.
- Heat source
- weighing paper
- Beaker (to heat water)
- Metric Ruler
- Ziploc Sandwich Bag
- 2 g. yeast (room temperature)
- 10 g. sugar
- 50 mL warm (38 degrees Celsius) water
- 50 mL graduated cylinder
- Stop watch or clock
- Be sure to keep all chemical,
heat, and glassware
safety rules that are specified by your teacher and in all general laboratory
experiences. Do not eat the yeast. Remember not to put a stopper into
any flask unless given direct instruction by your teacher.
water to 38 degrees Celsius
- measure 2 g. yeast and place in ziploc bag
- measure 10 g. sugar and place in ziploc bag
- measure 50 mL water and place in ziploc bag
- mix yeast, water and sugar with fingers in bottom of ziploc
- push air out of ziploc bag an seal
- roll ziploc from top down and measure thickness of ziploc
- start stopwatch at zero
- record measurement
- continue mixing yeast in bag with fingers
- record measurement of bag every 5 minutes
| Time (Minutes)
|| Size (cm)