How do you design a controlled experiment to appropriately test a hypothesis? at least 4 sentences, please.
subject is science but it only lets me pick biology i need the answer asap.

Step 1: Define your variables.  

Step 2: Write your hypothesis.  

Step 3: Design your experimental treatments.  

Step 4: Assign your subjects to treatment groups.

this protocol provides a detailed procedure for total protein extraction for western blot analysis from achieved samples following trizol isolation of rna.