The diagram given below represents an organ system in the human body. Study the same and answer the questions that follow:

Name the structural and functional units of the part marked 1.

Explanation

(i) Excretory system, (ii) Part 2 - Ureter
Part 4 - Urinary sphincter
Part 5 - Urethra is a membranous tube through which urine emptied from bladder is conducted to the exterior.
(iii)Part 1-Kidney
Nephron is the structural and functional unit of kidney.
(iv) Part 3 is the urinary bladder.
Urine is the fluid that is accumulated in the urinary bladder till a voluntary signal is given by the central nervous system (CNS).
Urea is the main nitrogenous waste present in the urine of mammals.