In this lab, breaking down of plant cell walls is primarily accomplished by:Group of answer choicesSaltDetergentEthanolStrainingMeat tenderizerBlending

In the lab focused on breaking down plant cell walls, the process is primarily accomplished by using meat tenderizer. This is because meat tenderizers contain enzymes like proteases, which help in breaking down proteins found in plant cell walls. Although other agents like salt and detergents can aid in cell lysis in different contexts, meat tenderizer is specifically effective for degrading cell wall components in plant tissues. The other options, such as ethanol and blending, may assist in other processes but are not primarily aimed at breaking down plant cell walls.

Thus, the correct answer is meat tenderizer.