Question

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.

Explanation:

To solve this, we analyze the nitrogen cycle. Producers (like plants) absorb nitrogen compounds (e.g., nitrates) from the soil through their roots (X). Free nitrogen (N₂) is abundant in the atmosphere (Y), and this is part of the nitrogen cycle flow. Other options have mismatched processes: photosynthesis is about carbon/energy, not nitrogen release/absorption directly as misrepresented in other options. The correct pair aligns with how producers take up nitrogen and the atmospheric nitrogen reservoir.

Answer:

X: Producers absorb nitrogen compounds through their roots.
Y: Free nitrogen is in the atmosphere.