Why do our eyes never dry out and what would happen if they did dry out?

Question: Why do our eyes never dry out and what would happen if they did dry out?
- Keywords:
  dry,
  eye
Asked by 10rc to Amy, Sarah, Will on 21 Jun 2012.
- Sarah Martin answered on 21 Jun 2012:
  
  Hi 10rc!
  
  Eyes can dry out – if you eat too little vitamin A, your eyes will get dryer and dryer and very sore, and the friction between your eye lids and your eye will make you go blind! So eating a carrot every so often for extra vitamin A is a really good idea.
  
  🙂 Sarah

Question: Why do our eyes never dry out and what would happen if they did dry out?