Question

question
why are polyester fluffs used in this experiment?
they are stronger than cotton balls, so they dont change when soybeans are added.
it makes no difference whether cotton balls or polyester fluffs are used.
they keep the humidity of the soybeans constant, so they continue to germinate.
they protect the seeds from touching the koh.

Explanation:

In an experiment with soybeans and KOH, polyester fluffs are often used to prevent the seeds from coming into direct contact with the caustic KOH, which could damage the seeds. Strength - related reasons are not the main factor, and there is a difference between using cotton balls and polyester fluffs in terms of protection and humidity - regulation properties. Keeping humidity constant is not the most typical reason for using polyester fluffs in this context.

Answer:

They protect the seeds from touching the KOH.