Question

Draw a labelled diagram of the excretory system of humans.

Answer 1

Hint: Excretory system is the system which removes wastes, and metabolic byproducts produced inside the body, in the humans, urea which is metabolic waste is expelled out from the blood through the kidney, while other solid wastes that are produced are go out through the intestine.

Complete answer:

Human excretory organs include:
- A pair of kidneys
- A pair of ureter
- Urinary bladder
- Urethra.

Kidneys:
- These are bean shaped organs which are present on the back side and they are present on either side, they are protected by the ribs and back muscles.
- The length of adult kidneys ranges from 10-12 cms and the width are 5 to 7 cms, when coming to weight, each ranges from 120 to 170 grams.
- The kidney outside is covered by the capsule, while the main kidney is divided into 2 parts, they are the outer zone called cortex and inner zone called medulla.
- The basic structural and functional of the kidney is nephrons, where each kidney approximately contains the 1.2 millions of the nephrons, and structure of nephron includes the corpuscular part and tubular part.
- Corpuscular part of the nephron, which is mainly located in the cortex part, and tubular part is mainly located in the medullary part.
- The structures such as blood vessels, nerve and ureter they all enter the kidney through hilum, and they have funnel shaped projections and spaces are present at that hilum area are called as renal calyx.
- The blood is purified by the nephrons, in the kidney and urine is formed, where this urine enters outside the kidney through the ureter.

> Ureter: These are pairs and they are muscular tubes which are thin, and come out of each kidney, and the main function of the ureters is to pass urine from the kidney to the urinary bladder.

> Urinary bladder: This is a muscular sac like structure which is useful to store urine, when it is filled completely, they are expelled to the urethra by a process called micturition.

> Urethra: This is the structure that is connected to the urinary bladder, and this urethra is useful to expel the urine out of the body, in the males it is the common route for the sperm and urine. And they are guarded by the sphincters.

Note: In some conditions, such as any infections to kidneys, and if there is decrease in the blood to the kidneys, and any some other reasons may results in failure of the kidneys, in such situations artificial system is placed which function like kidneys to filter the blood, and this process is called as dialysis.