(i) What is meant by blood pressure ? Which instrument the doctor uses to measure it ?
(ii) What is the harmful effect of high blood pressure on our health ?

Explanation

(i) Blood pressure is the pressure against the walls of the blood vessels produced by the discharge of blood into them by contraction of the left ventricle of the heart , sphygmomanometer.
(ii) A persistent high blood pressure results from narrowing arterial lumen and reduced elasticity of arterial walls in old age. It can cause repturing of capillaries and is a silent killer.