EXCRETORY SYSTEM
By Swagata
Sarkar
What Is Excretion ? Excretory Organs
Urinary System Production of Urine
Table of contents
01 The process of removal of harmful
and unwanted nitrogenous waste
products which are derived from
the
organism’s own metabolism.
02
Blood Supply
and
3 Major Steps
03 04
Along with their functions
Various parts:
• Kidneys
• Ureters
• Urinary Bladder
• Urethra
Excretion
A large amount of waste materials are
produced by metabolic activities. Such
materials are carbon dioxide , nitrogenous
waste etc. These materials become harmful if
retained inside our body in higher
concentration. So, our body has to remove
these materials through excretion.
The terms excretion, secretion and defecation
are different from each other.
• Defecation: removal of undigested food.
• Excretion: removal of metabolic waste like
urea, ammonia etc.
• Secretion: production of useful substance
like hormones, enzymes etc. by metabolism.
01
Excretory Organs
• Kidneys
• Lungs
• Skin
• Liver
02
Excretory organ Excretory products
1.Kidney Urea, uric acid,
ammonia, creatinine
through urine.
2.Liver Bile pigment
3. Skin(sweat gland) Sodium chloride,
water and traces of
urea through sweat.
4.Lungs Carbon di oxide
Different excretory organs
along with their excretory
products:
Parts Of Urinary
System:
Various parts:
 Kidneys
 Ureters
 Urinary Bladder
 Urethra
Parts Of Urinary
System In Detail:
Ureter:
 2 in number.
 Shape: bean shaped.
 Color: reddish brown.
 Size: 10 cm long and 6 cm wide.
 Location: located on either side
of backbone and protected by
the last two ribs.
 2 in number.
 Location: Each ureter arises from
the notch [hilum] in the median
surface of each kidney and connects
with urinary bladder.
 Function: Ureter carries urine from
kidney to urinary bladder.
 The front end of ureter is expanded
into the kidney and is called pelvis.
 1 in number.
 Location: lower part of the abdomen.
 Function: It temporarily stores urine.
 1 in number.
 Function: it carries urine to
outside of the body from urinary
bladder.
Kidney:
Urinary bladder:
Urethra:
Location and function of sphincter
muscles-
[Bladder sphincter and urethral sphincter] The sphincter
muscle guards the opening of urinary bladder into the
urethra.
It relaxes during the removal of urine.
Internal structure of kidney:
A longitudinal section of kidney shows 2 parts
➢
• Outer dark cortex
• Inner light medulla-- contains ‘renal pyramids’. Tip of
renal pyramids are called ‘papilla’.
• Composed of large no. of nephrons/ uriniferous
tubule/ renal tubules.
• Total no. of nephrons in each kidney- 2 million.
composed of 2 parts:
It is highly convoluted (folded) and as it
is proximal/ nearer to Bowman’s
capsule, so it is called proximal
convoluted tubule.
It is highly convoluted and as it is far
away from Bowman’s capsule, so it is
called distal convoluted tubule.
Detailed Structure Of Nephron:
Malpighian capsule:
PCT/ Proximal
convoluted tubule:
DCT/ Distal
convoluted tubule:
middle ‘U’ shaped part. It receives urine and
pass it to the pelvis.
Loop of Henle: Collecting duct:
Bowman’s capsule: thin
walled cup like structure.
Glomerulus: a knot like mass of
capillaries within the concavity of
Bowman’s capsule.
Production of Urine
Blood Supply To The
Uriniferous Tubules
3 Major Steps:
 Ultrafiltration
 Reabsorption
 Tubular Secretion
 A pair of renal arteries enter respective kidneys
 Inside each kidney, renal artery is divided and re-divided to form very fine
branches called arterioles.
 The arteriole that carries impure and oxygenated towards Bowman’s
capsule, called afferent arteriole.
 The afferent arteriole is divided into very fine capillaries and form a knot
like mass called glomerulus within the Bowman’s capsule.
 The capillaries of glomerulus reunite to form efferent arteriole and exit
the Bowman’s capsule.
 The efferent arteriole which carries pure blood, is again divided to form
secondary capillary network around renal tubule.
 Capillaries of secondary capillary network rejoin to form veins which
carry pure and deoxygenated blood.
 These veins join to form renal vein in each kidney and then they exit the
kidney.
Blood supply to kidney tubules:
Tubular secretion:
The filtration occurs under tremendous
pressure is called ultrafiltration. This
pressure occurs due to the difference in the
diameter of afferent and efferent arteriole.
The diameter of glomerular capillaries is
much less than the diameter of afferent
arteriole. Also the diameter of outgoing
efferent arteriole is two times narrower
than afferent arteriole. As the diameter is
decreasing, the pressure inside the fluid is
increasing. Because of this pressure, the
liquid part of blood along with urea,
glucose, amino acids and salts pass into the
renal tubule. This liquid in renal tubule is
called primary urine/ glomerular filtrate.
Walls of DCT secretes
potassium and certain
drugs like penicillin.
 Reabsorption in PCT: most
water, glucose, sodium and
chloride ions.
 Reabsorption in loop of Henle:
water and sodium ion.
 Reabsorption in DCT: remaining
chlorides and some water.
 Tubular reabsorption is called
‘selective reabsorption’- The
reabsorption of water and other
components is only to the extent
that the normal concentration of
blood is not disturbed.
Ultrafiltration:
Reabsorption:
Mechanism of urine
formation:
CREDITS: This presentation template
was created by Slidesgo, including
icons by Flaticon, and infographics
& images by Freepik
Thank
you!

Swagata Sarkar Biology Excretory System Documentation.pptx

  • 1.
  • 2.
    What Is Excretion? Excretory Organs Urinary System Production of Urine Table of contents 01 The process of removal of harmful and unwanted nitrogenous waste products which are derived from the organism’s own metabolism. 02 Blood Supply and 3 Major Steps 03 04 Along with their functions Various parts: • Kidneys • Ureters • Urinary Bladder • Urethra
  • 3.
    Excretion A large amountof waste materials are produced by metabolic activities. Such materials are carbon dioxide , nitrogenous waste etc. These materials become harmful if retained inside our body in higher concentration. So, our body has to remove these materials through excretion. The terms excretion, secretion and defecation are different from each other. • Defecation: removal of undigested food. • Excretion: removal of metabolic waste like urea, ammonia etc. • Secretion: production of useful substance like hormones, enzymes etc. by metabolism. 01
  • 4.
    Excretory Organs • Kidneys •Lungs • Skin • Liver 02
  • 5.
    Excretory organ Excretoryproducts 1.Kidney Urea, uric acid, ammonia, creatinine through urine. 2.Liver Bile pigment 3. Skin(sweat gland) Sodium chloride, water and traces of urea through sweat. 4.Lungs Carbon di oxide Different excretory organs along with their excretory products:
  • 6.
    Parts Of Urinary System: Variousparts:  Kidneys  Ureters  Urinary Bladder  Urethra
  • 7.
    Parts Of Urinary SystemIn Detail: Ureter:  2 in number.  Shape: bean shaped.  Color: reddish brown.  Size: 10 cm long and 6 cm wide.  Location: located on either side of backbone and protected by the last two ribs.  2 in number.  Location: Each ureter arises from the notch [hilum] in the median surface of each kidney and connects with urinary bladder.  Function: Ureter carries urine from kidney to urinary bladder.  The front end of ureter is expanded into the kidney and is called pelvis.  1 in number.  Location: lower part of the abdomen.  Function: It temporarily stores urine.  1 in number.  Function: it carries urine to outside of the body from urinary bladder. Kidney: Urinary bladder: Urethra:
  • 8.
    Location and functionof sphincter muscles- [Bladder sphincter and urethral sphincter] The sphincter muscle guards the opening of urinary bladder into the urethra. It relaxes during the removal of urine. Internal structure of kidney: A longitudinal section of kidney shows 2 parts ➢ • Outer dark cortex • Inner light medulla-- contains ‘renal pyramids’. Tip of renal pyramids are called ‘papilla’. • Composed of large no. of nephrons/ uriniferous tubule/ renal tubules. • Total no. of nephrons in each kidney- 2 million.
  • 9.
    composed of 2parts: It is highly convoluted (folded) and as it is proximal/ nearer to Bowman’s capsule, so it is called proximal convoluted tubule. It is highly convoluted and as it is far away from Bowman’s capsule, so it is called distal convoluted tubule. Detailed Structure Of Nephron: Malpighian capsule: PCT/ Proximal convoluted tubule: DCT/ Distal convoluted tubule: middle ‘U’ shaped part. It receives urine and pass it to the pelvis. Loop of Henle: Collecting duct: Bowman’s capsule: thin walled cup like structure. Glomerulus: a knot like mass of capillaries within the concavity of Bowman’s capsule.
  • 10.
    Production of Urine BloodSupply To The Uriniferous Tubules 3 Major Steps:  Ultrafiltration  Reabsorption  Tubular Secretion
  • 11.
     A pairof renal arteries enter respective kidneys  Inside each kidney, renal artery is divided and re-divided to form very fine branches called arterioles.  The arteriole that carries impure and oxygenated towards Bowman’s capsule, called afferent arteriole.  The afferent arteriole is divided into very fine capillaries and form a knot like mass called glomerulus within the Bowman’s capsule.  The capillaries of glomerulus reunite to form efferent arteriole and exit the Bowman’s capsule.  The efferent arteriole which carries pure blood, is again divided to form secondary capillary network around renal tubule.  Capillaries of secondary capillary network rejoin to form veins which carry pure and deoxygenated blood.  These veins join to form renal vein in each kidney and then they exit the kidney. Blood supply to kidney tubules:
  • 12.
    Tubular secretion: The filtrationoccurs under tremendous pressure is called ultrafiltration. This pressure occurs due to the difference in the diameter of afferent and efferent arteriole. The diameter of glomerular capillaries is much less than the diameter of afferent arteriole. Also the diameter of outgoing efferent arteriole is two times narrower than afferent arteriole. As the diameter is decreasing, the pressure inside the fluid is increasing. Because of this pressure, the liquid part of blood along with urea, glucose, amino acids and salts pass into the renal tubule. This liquid in renal tubule is called primary urine/ glomerular filtrate. Walls of DCT secretes potassium and certain drugs like penicillin.  Reabsorption in PCT: most water, glucose, sodium and chloride ions.  Reabsorption in loop of Henle: water and sodium ion.  Reabsorption in DCT: remaining chlorides and some water.  Tubular reabsorption is called ‘selective reabsorption’- The reabsorption of water and other components is only to the extent that the normal concentration of blood is not disturbed. Ultrafiltration: Reabsorption: Mechanism of urine formation:
  • 13.
    CREDITS: This presentationtemplate was created by Slidesgo, including icons by Flaticon, and infographics & images by Freepik Thank you!