if something evaporation something else then that something is the sink of that something else & animal are a sink of space through siberian ->  plants release oxygen during photosynthesis  a vegetable absorbs oxygen oxygen from the land to perform yellow & to absorb something can nice to give something in ->  a plant takes in carbon dioxide to perform photosynthesis  plants release oxygen during photosynthesis & a plant takes in carbon dioxide to perform photosynthesis -> plants take in carbon dioxide and release oxygen during photosynthesis