What is an observational study? How is it different from a controlled experiment?

If a cell's main function is to produce proteins to be excreted, which organelles would you expect to be larger

This is one form of rna that transports a specific amino acid to a ribosome during protein synthesis.

What conclusion can be made based on the temperature of soil when the light hits the soil at 0°, 45°, and 90° angles in section 2 of the experiment? did your results support your hypothesis? why or why not?