BIOCHEMISTRY QUESTIONS

Glycogen, cellulose, polypeptides and phospholipids all have large molecules.  
(a)   Which of these molecules is  
  (i) not found in a plant cell;  
      (1)
  (ii) used primarily as a structural molecule?  
      (1)
(b)   Give one element found in polypeptides that is not present in those of glycogen, cellulose or phospholipids.  
      (1)
The diagram represents a phospholipid molecule  
     
(c)   Name the following parts of the molecule  
  (i) A  
      (1)
  (ii) B  
      (1)
  (iii) C  
      (1)
(d)   Phospholipids are found in cell membranes. Proteins are also found in cell membranes, give two functions of proteins in cell membranes  
    (2)