(a(i))[2]
Calculate the percentage of total human body mass that is made up by the three most common elements.
(a(ii))[2]
Name two kinds of substance in the human body that consist only of carbon, hydrogen and oxygen.
(b(i))[3]
Discuss why water accounts for such a large proportion of an adult’s total body mass.
(b(ii))[3]
Explain why a cell from human tissue bursts when it is placed in water.
(c)[2]
Suggest one tissue with a relatively high percentage mass of nitrogen and explain your answer.