HOW CAN WE OBSERVE RESPIRATION

CELL ENERGY - 4

PURPOSE – To track the amount of Carbon Dioxide that is produced as a waste product during human respiration.

MATERIALS NEEDED – Cabbage indicator, test tubes, test tube racks, straws, and a clock.

PROCEDURE –

1. Obtain the needed materials

2. Prepare a control for our exercise by filling a test tube one quarter full of cabbage indicator.

3. Next, fill test tubes one quarter full of cabbage indicator, one test tube for each member of your group

4. Each individual will use a straw to exhale into their test tube

5. Exhale all of your outgoing gas through the indicator liquid. DO NOT INHALE THE LIQUID!

6. Note the starting time for everyone (if everyone starts at the same time, this would be easier.)

7. Each individual will exhale for a different time period.

8. One individual for 30 sec

9. One individual for 1min

10. One individual for 3min

11. One individual for 5min

12. After the each individual is finished, write down the color of the indicator liquid in the table below!

DATA -

	Control	30 sec	1 min	3 min	5 min
color

ANAYLYSIS –

1. Describe the color change over the span of five minutes.

2. What is causing the color change?

3. What does this activity show us about respiration in Humans?

4. Where does respiration occur in Humans?

5. During what part of respiration is CO₂released? (Not breathing, but respiration…)