Investigating Human Respiration (Developed by SEPUP)
kit #803S
Students explore the role of the respiratory system in the regulation of gases in the blood. Students qualitatively investigate the use of bromthymol blue (BTB) as an indicator. They then quantitatively measure the amount of carbon dioxide in their exhaled breath by using the indicator to perform a simple titration.
Scientific Concepts:
• Creating models is one way to understand and communicate scientific information
• Each system within the human body is defined by the functions that it performs
• Lungs provide surface area for oxygen to enter and carbon dioxide wastes to leave the blood
• An indicator can help measure changes, such as shifts in the concentration of carbon dioxide present in a solution
- Creating models is one way to understand and communicate scientific information
- Each system within the human body is defined by the functions that it performs
- Lungs provide surface area for oxygen to enter and carbon dioxide wastes to leave the blood
- An indicator can help measure changes, such as shifts in the concentration of carbon dioxide present in a solution
Content List in Investigating Human Respiration (Developed by SEPUP) is as follows:
Quantity | Description |
---|---|
1 | Teacher’s Guide with MSDS |
32 | Student Worksheets and Guides |
24 | Plastic cups |
4 | Bromthymol blue (BTB) Indicator, Dropper bottle |
8 | 0.05 M sodium hydroxide, Dropper bottle |
8 | SEPUP trays |
8 | Droppers |
16 | Stir sticks |
16 | Cups, 30-mL, graduated |
16 | Plastic bags, 1-gallon |
18 | Straws |
- Recommended number of students
- 32 maximum per class
- Number of groups
- 8 groups per class
- Number of classes
- 1 (8 groups of 4 students)

To complete this kit requires one to two ~50-minute class periods.