Given that CO2 is produced by cellular respiration, why does the amount of CO2 in the atmosphere remain relatively constant? (When answering this question, exclude the impact of human activities on atmospheric CO2.)
◦ CO2 is converted to carbohydrates in photosynthesis.
◦ CO2 mostly forms carbonate rocks.
◦ CO2 is split apart during photosynthesis.
◦ CO2 is trapped in dead organisms' bodies.