Question

Given below is a simple diagram of the human kidney cut open longitudinally. Answer the following questions:

(i) Give the definition of excretion.

(ii) Name the units of the kidney.

(iii) Why does the cortex of the kidney show a ‘dotted’ appearance ?

(iv) Mention two functions of the kidney.

(v) Write two differences in the composition of the blood flowing through blood vessels A and B.

Answer 1

(i) Excretion is the process of removal of all harmful and unwanted products especially nitrogenous products from the body of living beings.

(ii) The units of the kidney are nephrons.

(iii) The dotted cortex of kidney shows the presence of nephrons (Bowman’s Capsule) in this region.

(iv) Two functions of kidney are:

(a) It expels out all the nitrogenous products produced in the body.

(b) It helps in osmoregulation.

(v) Two differences in the composition of blood flowing through blood vessels A and B are:

(a) A contains blood having large amount of water and nitrogenous wastes while blood in B is thicker and free from toxic substances.

(b) B carries more O₂ and nitrogenous waste product as it is Renal Artery.

A carries CO₂ and no nitrogenous products.