AP Biology Lab 6
Cellular Respiration
Brainstorm:
 What factors can affect the rate of cellular
respiration?
Lab Notes
 Respirometer: used to measure volume of O2 consumed
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during respiration
As CO2 is produced, it will be removed by KOH.
 CO2 (gas) + 2KOH  K2CO3 (solid) + H2O
 As O2 is consumed, gas volume in respirometer decreases
Control: respirometer with nonliving matter (glass beads)
 Measure changes in temp. and air pressure
Equilibration: assembled respirometers sit in H2O for 5
min. before data is collected
Data collection: measure O2 consumed every 5 min. for 30
min. total
Respirometers
Equilibration of Respirometers
Materials
 See lab handout.
 Supplies available today:
 Germinating seeds (48 hr germination): sugar
snap peas, lima beans, navy beans, lentils, beets
 Germinating seeds (24 hr germination): sugar
snap peas, lentils
 Non-Germinating seeds: same as above
 Pillbugs
 …Your choice!
Inquiry Investigation
 Lab Group Problem: How does _____ affect
cellular respiration?
 Hypothesis (If…, then… because…)
 Experimental Design (IV, DV, control,
constants, etc.)
 Materials
 Procedure (Simple flow chart)
 Data Table (see next slide)
Sample Data Table
Difference (Diff.) = (initial reading at time 0) – (reading at time X)
Corrected Difference (Corr. Diff.) = (Initial pea reading at time – pea seed reading at
time X) – (initial bead reading at time 0 – bead reading at time X)
Analysis & Conclusion
 Analysis:
 Graph (O2 consumed vs. time)
 Use corrected difference values for O2
consumed
 Determine respiration rates (Use lines of bestfit for this lab)
 Compare class data
 Conclusion – Explanation Tool