2. Urinary System Of Goat
 Presented To:
 Sir Zeeshan Akbar Sb.
 Presented By:
 14-Arid-2030
 14-Arid-2029
 14-Arid-2028
 14-Arid-2036

 DVM 1st (Evening)
 Group (A)

3. Homeostasis
 The urinary system maintains homeostasis in
several ways:
 Removal of urea (nitrogenous waste) from the
bloodstream.
 Control of water and salt balance in the bloodstream.
 Involved in blood pressure regulation.

4. Renin
 Renin is an enzyme released by the kidneys in
response to a drop in blood pressure.
 Renin catalyzes the production of angiotensin, a
hormone that causes arterioles to constrict, raising
blood pressure. This also causes water retention.
How does this maintain homeostasis of blood
pressure?

5. Erythropoietin
 A second response to low blood pressure is the
release of erythropoietin, another hormone.
 Erythropoietin travels to the bone marrow and
stimulates the production of new blood cells. How
does this maintain homeostasis?

6. Amino acid metabolism Amino acids are the
building blocks of
protein. If not needed
for building protein,
then can be
metabolized for energy,
or broken apart and the
carbon chains used to
make fat.
 Metabolism requires
removal of the amine
unit (NH3).

7. Regulating water
 Antidiuretic hormone (ADH, also called
vasopressin) is part of a negative feedback system
that regulates water in the mammalian body.
 ADH increases the permeability of the distal tubule,
allowing greater water recovery.

9. Ammonia and Urea
 Ammonia is toxic and highly water soluble.
 The liver turns ammonia into urea, which is less
toxic and less soluble.

10. Urinary system anatomy
 Main structures of the urinary system:
 kidneys
 ureters
 bladder
 urethra

11. Anatomy of the Kidney
 Main structures of the mammalian kidney:
 renal cortex
 renal medula
 renal pelvis
 nephrons

12. Outline
 Uriniferous tubule (anatomical unit for forming urine)
 Nephron
 Renal corpuscle (in cortex)
 Glomerulus (tuft of capillaries)
 Glomerular (Bowman’s) capsule
 Tubular section
 Proximal convoluted tubule
 Loop of Henle
 Distal convoluted tubule
 Collecting duct
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13. Anatomy of the Nephron
 Glomerulus
 Proximal tubule
 Loop of Henle
 Distal tubule

14. Glomerulus This is the only place
in the system where
the blood is actually
“filtered.”
 Blood pressure is
used to push plasma
through capillary
walls and into the
Bowman’s capsule.

15. Proximal tubule
 Nutrients (salts, vitamins, etc.) are moved out of the
tubule through active transport.
 Water follows the nutrients by osmosis.

16. Loop of Henle Tissue around the
Loop of Henle is
salty, from active
transport and
diffusion of
sodium chloride.
 The salty
conditions allow
water to diffuse out
of the loop.

17. Distal tubule
 Active transport
is used to move
more nutrients
out of the
concentrated
urine.
 Some ions,
drugs, and toxins
are actively
pumped into the
tubule.

18. Collecting Duct  More water
leaves the tube
by osmosis, since
the tube is
surrounded by
salty tissue.
 Some urea leaves
by diffusion, and
may be cycled
through the
system.

20. Vessels
 Afferent and efferent arterioles associated with glomerular capillaries
 Allows high pressure for forcing filtrate out of blood
 About 20% of renal plasma flow is filtered each minute : this is the glomerular filtration
rate (GFR), an important clinical measure of renal function
 This is about one liter every 8 minutes (only 1% ends up as urine)
 Peritubular capillaries arise from efferent arterioles
 Absorb solutes and water from tubule cells
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21. 21

22. The Vasa recta is a
portion of the
peritubular capillary
system which enters the
medulla where the solute
concentration in the
interstitium is high. It
acts with the loop of
Henle to concentrate the
urine by a complex
mechanism of counter
current exchange using
urea. If the vasa recta did
not exist, the high
concentration of solutes
in the medullary
interstitium would be
washed out.
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____vasa recta
(vessels, continued)
The Vasa recta

23. For studying
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Parts of the kidney:
1. Renal pyramid
2. Efferent vessel
3. Renal artery
4. Renal vein
5. Renal hilum
6. Renal pelvis
7. Ureter
8. Minor calyx
9. Renal capsule
10. Inferior renal capsule
11. Superior renal capsule
12. Afferent vessel
13. Nephron
14. Minor calyx
15. Major calyx
16. Renal papilla
17. Renal column

24. The Ureters
 Slender tubes leaving each
renal pelvis
 One for each kidney
carrying urine to the
bladder
 Run medially within
posterior bladder wall
before opening into
interior
 This oblique entry helps
prevent backflow of urine
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25. Ureters play an active role in
transporting urine (it’s not
just by gravity)
Three basic layers
 Transitional epithelium
of mucosa stretches
when ureters fill
 Muscularis
 Inner longitudinal, outer
circular layers
 Inferior 3rd with extra
longitudinal layer)
 Stimulated to contract
when urine in ureter:
peristaltic waves to
propel urine to bladder
 Adventitia (external)
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26. Urinary Bladder  Collapsible muscular
sac
 Stores and expels urine
 When full it become
ovoid.
 In male it is dorsaly
related to the rectum,
ductusdeference and
acessary sex glands
 In female it is related
with body of uterus and
vagina.
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27. Urethra
 Extends to the tip of the
penis, where it exit the
body.
 Used to empty the
urinary blader.
 Surrounded by smooth
muscle crucial for
ejaculation.