1. Lab 5: Cell Respiration
Respiration equation
C6H12O O CO H energy
We will measure O2 consumed.
How can we measure O2 (gas) used when CO2 (gas) is produced?
- KOH – removes CO2 by forming a precipitate

2. After placing respirometer under water, the crickets continue to breathe.
As crickets breath & use up the air in the respirometer, water moves down
pipet. We can measure this as O2 used for respiration.

3. Respirometer set up
We will use:
Mealworms
Only 2 respirometers

4. Set-up: stop after step 7
do NOT get water
Data collection:
- get water
- begin step 8..

5. Ideal gas law PV = nRT
- P = pressure of the gas
V = volume of the gas
n = number of molecules of gas
R = gas constant
T = temperature of gas (°K)
By keeping T & P constant, V is directly proportional to n
PV = nRT
How will we correct for T & P and keep them constant?
vial with glass beads
glass beads are not alive (SHOCKER!)`, changes here reflect
table bumps, etc
Changes in atmospheric Temp & Pressure
We must subtract out these changes
Difference = initial reading – reading at time x
t0 – tx
Corrected difference = Worm difference – glass bead difference

6. Lab Notebook Format 1) Title/Date 2) Pre-Lab (Parts A, B, C as usual)
3) Purposes (2-3)
4) Personal Account
Hypothesis, Procedure (all steps), Data Table, Graph, Reaction Rate Calculations
5) Discussion Questions (#1-8)
Exclude #3
6) Conclusion