Question

Explain human excretory system ​

Answer 1

$\huge \boxed{ \underline{ \rm \pink{ANSWER - }}}$

Parts of Human Excretory System :-

⚙️2 Kidneys

⚙️2 Ureters

⚙️1 Urinary bladder

⚙️1 Urethra

$\huge \underline{ \bf \orange{kidney - }}$

Kidneys are the main organ of the human excretory system. The kidneys are paired organs in each individual. They are the primary excretory organ in humans and are located one on each side of the spine at the level of the liver. They are divided into three regions- the renal cortex which is the outer layer, the renal medulla which is the inner layer and the renal pelvis which is responsible for carrying the urine from the kidney to the ureter. The functional unit of a kidney is called the nephron.

$\huge \underline \bold \red{ureter - }$

There is one ureter that comes out of each kidney as an extension of the renal pelvis. The ureter is a thin muscular tube that carries urine from the kidneys to the bladder.

$\huge \underline{ \rm \purple{Urinary \: Bladder - }}$

It is a sac-like structure that is lined with smooth muscle layer and is responsible for storage of urine till it is expelled from the body by micturition. Micturition is the act of expelling urine from the body. The bladder receives urine from the ureters, one from each kidney. The level of the urinary bladder placement in the body differs in men and women.

$\huge \underline \mathfrak{Urethra - }$

This is a tube that arises from the urinary bladder and functions to expel urine to the outside by micturition. The urethra is shorter in females and longer in the males. In males, the urethra functions as a common path for sperms and urine. The opening of the urethra is guarded by a sphincter that is autonomically controlled.

Each kidney consists of the following parts:

Bowman’s capsule– is the first part of the nephron which is a cup-shaped structure and receives the blood vessels. The glomerular filtration occurs here. The blood cells and proteins remain in the blood.

Proximal Convoluted Tubule– The Bowman’s capsule extends downwards to form the proximal tubule. Water and reusable materials from the blood are now reabsorbed back into it.

The loop of Henle– The proximal tubule leads to the formation of a u-shaped loop called the Loop of Henle. The Loop of Henle has three parts: The descending limb, the u-shaped bend, and the ascending limb. It is in this area that the urine becomes concentrated as water is reabsorbed. The descending limb is freely permeable to water whereas the ascending limb is impermeable to it.

Distal Convoluted Tubule– The Loop of Henle leads into the distal convoluted tubule which is where the kidney hormones cause their effect. And the distal convoluted tubule leads to the collecting ducts.

Collecting Duct– The distal convoluted tubule of each nephron leads to the collecting ducts. The collecting ducts together form the renal pelvis through which the urine passes into the ureter and then into the urinary bladder.

Answer 2

Answer:

The excretory system in human beings consists of following main organs : two kidneys, two ureters, bladder and urethra. The function of the kidney is to remove the poisonous substanc pile urea, other waste salts and excess water form the blood and excrete them in the form of yellowish liquid called urine.

Each kidney has a large number of

Excretory units called nephrons. It consists of bowman's capsule containing a bundle of blood capillaries called glomerulus. The function of glomerulus is to filter the blood passing through it. During filtration useful substances are absorbed back to the blood. The urine( unwanted substances) passes through ureter and then to urinary bladder. The urine is stored for sometime and ultimately passes out of the body through urethra.