Final answer:
Elastic fibers in the LM appear as wavy lines in prepared slides and are made up of proteins like elastin. They have the property of returning to their original shape after being stretched or compressed.
Step-by-step explanation:
Elastic fibers are a type of connective tissue fiber that contains the protein elastin and other proteins. These fibers have the property of returning to their original shape after being stretched or compressed. In the light microscope (LM), elastic fibers appear as wavy lines in prepared slides. They are particularly prominent in elastic tissues such as skin and the elastic ligaments of the vertebral column.