Question

Explain why the plant lives and the mouse dies in this experiment discussing photosynthesis, cellular respiration, and their inputs and outputs.

Experiment- Plant, mouse, candle placed in a sealed jar. The air in the container was composed of 78% N2, 21% O2, 0.04% CO2, and 1% water vapor

Answer 1

0.04% of CO2 is the optimum concentration of carbon dioxide required for the plants for carbon fixation.

Light from the candle and CO2 are used for the photosynthesis and the released oxygen is utilized back by the candle itself.

The mouse competes with the candle for the liberated oxygen.

The candle require oxygen for combustion which is rapid process occurs at the oxygen source whereas the mouse requires oxygen as it is the final electron acceptor in the cellular respiration which occurs endogenously in the mouse.

The experiment will be at equilibrium for a while without mouse i.e., oxygen utilized by candle is equal to oxygen released from the plant and plant utilizes CO2 released from candle.