The diagram below shows the human digestive system.  

a   Name the structures labeled.  
  (i) C: oesophagus (1)
  (ii) A: liver (1)
b   Give the letter of a structure where the following are produced  
  (i) Amylase: X or E  
  (ii) Maltase: F  
  (iii) Bile: A (3)
The diagram below shows the structure of the small intestine  

c   Name the structures labeled.  
  (i) A: villi (1)
  (ii) B: microvilli (1)
d   Explain what their significance is  
  • They increase surface area
  • For absorption of the products of digestion