Question

Given below is a diagram of a human kidney cut open longitudinally Answer the following:
Figure

(i) Given definition of excretion.
(ii) Name the unit of kidney.
(iii) Why does the cortex of kidney show dotted appearence.
(iv) List the functions of the kidney.

Answer 1

(i) Excretion is a biological process by which metabolic waste products and toxic materials are removed from the body of an organism.

(ii) Nephrons are the structural and functional unit of the kidney.

(iii) The cortex of the kidney shows a dotted appearance because it consists of numerous nephrons, which are its structural and functional units.

(iv) The functions of the kidney are as follows:

• Absorption of water and salt
• Removal of waste materials like urea, ammonia etc., from blood
• Control of blood pressure