(b) There is a pair of bean - shaped organs P in the human body towards the back, just above the
waist. A waste product Q formed by the decomposition of unused proteins in liver in brought
into organ P through blood by an artery R.
(i) What is the organ P ?
(ii) Name the artery R.
(iii) Name are tiny filters S known as ?
(iv) What is the waste substance Q ?