Whats the most abundant element in the atmosphere?

Sydney drew a flow chart to illustrate the nitrogen cycle.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.

Which statement is true about the cell theory? a) it is well-supported by evidence. b) it is unchangeable and permanent.

Works together in the synthesis, modification, packaging, and transport of lipids and proteins