The diagram below shows the structure of a chloroplast.  

a.   Name the process that occurs in chloroplasts  
b   Name the structures labeled.  
  (i) X.  
  (ii) Y  
c   Give two similarities in structure between chloroplasts and mitochondria.  
d   Some scientists think that chloroplasts and mitochondria have evolved from intracellular symbiotic bacteria. Explain why  
    the structures of mitochondria and chloroplasts can account for this hypothesis.