Effects of Germination Time Length on Pea Respiration Problem: What effect does germination time have on pea respiration?

Background With glucose and oxygen, plants are able to perform cellular respiration, creating CO2; this process extracts free energy from carbon compounds for ATP production. Different factors, like germination period, impact the rate of cellular respiration.

Hypothesis As the length of germination of the pea plants increases, the rate of cellular respiration will increase because more oxygen will be needed as the plant grows.

Procedures 1. Soak different sets of peas for 24, 48, and 72 hour periods. 2. Put 25 peas for each time in their respective test tube. Add glass beads to compensate for difference in volume, maintaining a volume of 10 mL determined through water displacement. 3. Record pressure changes for 900 seconds.

Data Table: Room Temperature: 18 degrees Celsius. Length of Germination Volume of Peas in Test Tube Volume of Glass Beads Rate of Change in Pressure (kPa/sec) 24 hours 8 mL 2 mL -7.753e-5 48 hours -0.001253 72 hours 10 mL 0 mL -0.001989 Control -0.0006832

Results Pressure 1: 72 hour period Pressure 2: 48 hour period

Results Cont. Pressure 1: 48 hour period Pressure 2: Control (Only Beads)

Discussion Different weather conditions give different amounts of moisture availability Peas have higher cellular respiration rates with more germination time Useful in agriculture to determine optimal germination period, optimise plant growth In different weather conditions that change the amount of moisture availability, the peas undergo higher rates of cellular respiration when allowed more germination time. Therefore, farmers can know how long the best germination period is.

Conclusion 72 hours best time for cellular respiration based on 3 tested time periods Expect plateau in increase of cellular respiration rate sometime beyond germination time of 72 hours Other conditions to consider to maximize growth: Temperature Air Pressure Moisture Amount After conducting this experiment, we expect a plateau in the increase of cellular respiration rate beyond a germination period of 72 hours. Based on the 3 time periods we could test, 72 hours is the best time for optimal cellular respiration. In order to find the very best conditions for peas to grow, the impact of temperature, air pressure, and moisture amount should also be considered.

Experimental Errors Did not run control while testing peas Experienced changes in pressure for the control Did not keep the amount of water that the peas were submerged in constant during respective soaking periods We should have ran the control at the same time we were testing the peas. By running the control by itself we had nothing to compare it to, especially considering that there was a change in pressure for the control (we account for this by problems with the gas pressure sensors). Also we should have kept the amount of moisture we submerged the peas in constant.