Section 1: The Diversity of Cells

     Most cells are so small

         they can't be seen

             by the naked eye.

     So how did scientists

         find cells?

     By accident,

         that's how!

     The first person

           to see cells

        wasn't even looking for them.

     All living things

         are made of tiny structures

              called cells.

     A cell

          is the smallest unit

        that can perform

             all the processes

                 necessary for life.

     Because of their size,

         cells weren't discovered

             until microscopes

                   were invented

                 in the mid-1600s.