Final answer:
As the percentage of acrylamide in a polyacrylamide gel decreases, the pore size within the gel increases. The ratio of acrylamide to methylenebisacrylamide determines this pore size, affecting the gel's ability to separate molecules based on size during electrophoresis.
Step-by-step explanation:
As the percentage of acrylamide in a polyacrylamide gel decreases, the pore size of the gel increases. The gel is composed of a polymer of acrylamide and methylenebisacrylamide, where the latter is responsible for the crosslinks between acrylamide chains, resulting in a porous structure. The crosslinking ratio, which is the ratio of acrylamide to methylenebisacrylamide, determines the pore size, with a higher ratio indicating a gel with smaller pores, suitable for separating smaller RNAs or proteins.
When working with polyacrylamide gel electrophoresis (PAGE), it is crucial to adjust the acrylamide concentration appropriately to achieve the desired separation based on the size of the biomolecules being analyzed. The process of free-radical polymerization is utilized to generate the polyacrylamide medium, where the careful selection of the acrylamide:methylenebisacrylamide ratio allows for precise control over the pore size within the gel matrix.