Sydney drew a flow chart to illustrate the nitrogen cycle. Flow chart of the nitrigen cycle. Box 1: uppercase X. Box 2: Bacteria fix nitrogen from the air. Box 3: uppercase Y. Box 4: Consumers eat other organisms. Box 5: Decomposers break down dead organisms. Which labels best complete the flow chart? X: Producers undergo photosynthesis. Y: Nitrogen compounds are released into the air. X: Nitrogen compounds are released into the air. Y: Producers undergo photosynthesis. X: Free nitrogen is in the atmosphere. Y: Producers absorb nitrogen compounds through their roots. X: Producers absorb nitrogen compounds through their roots. Y: Free nitrogen is in the atmosphere.