4. What are the main
structures of the human eye?

Gap-fill exercise

Fill in all the gaps, then press "Check" to check your answers. Use the "Hint" button to get a free letter if an answer is giving you trouble. You can also click on the "[?]" button to get a clue. Note that you will lose points if you ask for hints or clues!
The main structures of human eye
are the , the iris, the pupil,
ciliary muscles, the crystalline and
the retina (the between the
crystalline lens the retina within the
is filled with vitreous ).