This question was attempted by many candidates and their performance was fair.  In part (a) candidates correctly define antibody.  In part (b)(i) candidates correctly mention disease of the blood vessels and in (b)(ii) candidates could  not correctly state causes of arterioscleriosis, they wrote wrong answers such as blood not mixed, blood effected and blood not  moved among others. In part (c) candidates correctly state preventive measure of coronary heart diseases.

However, the expected answers were as follows:

5 (a)  Antibody
Antibody is a protective substance produced by the white blood cell to fight against diseases responses to antigenic attack in the human body.
               
   (b)(i)  Diseases of the blood vessels

              -    hypertension/high blood pressure
              -    arteriosclerosis
              -    thrombosis/embolism
              -    varicose veins
              -    haemorrhoids/pile

       (ii)   Causes of arteriosclerosis

•  degeneration of the arterial walls/thickening of arterial walls/narrowing of   lumen
• high intake of sugar
• obesity/overweight
• heredity
• high intake of animal fat/inability to control diet
• heavy smoking
• aging
• inadequate exercise/lack of exercise

(c)        Preventive measures of Coronary heart disease
            -   control of diet/avoid intake of animal fat
            -   regular exercise
            -   avoid smoking
            -   Keep body weight at a reasonable level/healthy eating habit
            -    avoid high intake of sugar/sugary food
            -    adequate rest
            -    regular medical check-up