The great contribution of Schwan was

what he saw
how interpreted what he saw
cell theory
None of the above

The correct answer is: B. how interpreted what he saw

Schwann was a German physician and anatomist who is best known for his work on the nervous system. He was the first to describe the structure of the myelin sheath, which is a fatty layer that surrounds nerve fibers. Schwann also proposed the cell theory, which states that all living things are made up of cells.

Schwann’s interpretation of what he saw was revolutionary. He realized that the myelin sheath was not just a random structure, but was actually there to protect and insulate nerve fibers. This discovery helped to explain how nerve impulses are transmitted, and it paved the way for future research on the nervous system.

The other options are incorrect because:

  • Option A is incorrect because Schwann’s contribution was not just what he saw, but also how he interpreted what he saw.
  • Option C is incorrect because Schwann did not propose the cell theory. The cell theory was proposed by Matthias Schleiden and Theodor Schwann in 1839.
  • Option D is incorrect because Schwann did make a significant contribution to science.