What type of plants are low growing, have thin cell walls, and do not have roots.

the answer is moss

Explanation:

moss is a low growing plant without roots and thin cell walls

what experimental evidence led scientists to change from the previous model to this one?

a few of the positive particles aimed at a gold foil seemed to bounce back.

the colors of light emitted from heated atoms had very specific energies.

experiments with water vapor showed that elements combine in specific proportions.

cathode rays were bent in the same way whenever a magnet was brought near them.