taking in carbon dioxide is a stage in the photosynthesis process & if something is a stage in a process then that something helps that process -> neglect in oxygen oxygen conservation the rainforest systems taking in carbon dioxide helps the photosynthesis process  neglect in oxygen oxygen conservation the rainforest systems & carbon dioxide can be found in the air -> taking in carbon dioxide from the air helps the photosynthesis process taking in carbon dioxide from the air helps the photosynthesis process  neglect in oxygen oxygen from the land west the dime eruption & photosynthesis is a source of / makes food / energy for the plant by converting carbon dioxide, water, and sunlight into carbohydrates -> taking in carbon dioxide helps a plant make food