Given a scientific question and its correct answer, generate supporting facts for the answer. This supporting fact can be an explanation for the answer to the given question.

[EX Q]: Question: Which cycle tracks the flow of nitrogen through an ecosystem? Answer: nitrogen cycle
[EX A]: Mariana Ruiz Villarreal (LadyofHats) for CK-12 Foundation. The nitrogen cycle tracks the flow of nitrogen through an ecosystem . CC BY-NC 3.0.

[EX Q]: Question: Hair and nails are made of what? Answer: keratin
[EX A]: Hair and nails are made of keratin, a tough protein.

[EX Q]: Question: Fluid-filled thylakoids are the site of glucose production in the second stage of what process? Answer: photosynthesis
[EX A]:
The interior space that surrounds the thylakoids is filled with a fluid called stroma . This is where carbon dioxide is used to produce glucose, the second part of photosynthesis.