This document discusses how cells obtain energy from food and sugar. It outlines an investigation where students will test different cereals to see which contains the most sugar by measuring the carbon dioxide produced during cellular respiration. Yeast will break down any sugar in the cereal samples to produce carbon dioxide, and more sugar will lead to more carbon dioxide production. The document also asks questions about cellular respiration and how plant and human cells obtain energy.

1. Sugar and Cells
Investigation 3 - Part 3

2. Cellular Respiration
Questions
• Why do people eat food?
• How do your cells get energy from the food
you eat?
• How to plant cells get the energy they need?
• What happens during cellular respiration?

3. Testing Cereals
• Selection of different breakfast cereals
– Do you think they might contain sugar?
– Which one has the most sugar and which has
the least?
– Can you design an investigation to find out?
• 3 minutes - talk in groups to outline an
investigation for testing the cereals for
sugar content

4. Plan
• Test 2 cereals
– Possible “high sugar” and “low sugar”
– Mrs. L will test control with 3 gr pure sugar
• Amounts per bag
– 2 spoons yeast
– 3 grams cereal
– 50 ml water (40-50ºC)
• Measure CO2 @ 10 min. & 20 min
• Write up plan on Sugar Test A

5. Testing
• Record CO2 levels on Sugar Test B and
class chart @ 10 min. & 20 min.
• Evaluate Results
– Yeast breaks down sugar for energy
– Produces carbon dioxide as waste
– The more sugar: The more carbon dioxide
• Rank cereals and write conclusion

6. Homework
• Read Living with Diabetes, pg 127-130
• Read Summary: Sugar and Cells, pg
131-133 and answer questions
• I-check 3 on Thursday(14) or Friday (12
and 15)
• Start reviewing f6or Living Systems
Unit Test, Wed. 11/17(14 & 12), Thurs.
11/18(15)

7. Sugar and Cells
• What does chlorophyll do?
• What raw materials do plants use to
make sugar?
• Why do plants make sugar?
• What happens to sugar when it is used
in cells?
• How do your cells obtain energy from
the Sun?