Download The Urinary System

The Urinary System
OVERVIEW
https://www.youtube.com/watch?v=lfGYd1
wrTgE&list=PLR6xLyq3PY7GVj1h5mFQ9Y9mMj_jnmWQ
Bozeman
 https://www.youtube.com/watch?v=qfWx8
msgHqM

Function
1. Remove nitrogenous wastes
2. Maintain electrolyte(ions), pH
(acid-base), and fluid balance of
What does this mean?
blood
It regulates the water and salt in the body.
So…
3. Homeostatic
organ
whatever excess we have,
4. Acts
asusblood
it helps
get rid offilter
it.
5. Release hormones
Kidneys as Filters
• Average kidney filtration rate
= 180 liters (50 gal) of blood/day
• 178-179 liters are reabsorbed back
into blood
Nitrogenous
Wastes
urea
uric acid
ammonia
kidneys
Organs
of the
Urinary
System
ureters
urinary
bladder
urethra
Check your kidney diagram

Calyx





Renal column
Medullary pyramid
Pelvis
Fibrous capsule
Renal cortex
Kidney
Anatomy
renal
pelvis
ureter
renal
pyramids
renal
cortex
renal
capsule
renal
medulla

http://www.youtube.com/watch?v=cc8sUv
2SuaY&feature=related
Nephron = nephron
functional unit of kidney
Each kidney contains > 1,000,000 nephrons.
renal artery
renal vein
Kidney
Anatomy
blood
Nephron
Functioning
filtration
tubular
reabsorption
and secretion
urine “refreshed” blood
efferent
arteriole
afferent
arteriole
glomerulus
artery
peritubular
capillaries
loop of
Henle
vein
Bowman’s
capsule
proximal
convoluted
tubule
distal
convoluted
tubule
collecting
duct
Glomerulus
DCT
Each kidney contains
over 1 million nephrons
and thousands of
collecting ducts PCT
Collecting duct
Loop of Henle
renal
cortex
renal
medulla
efferent
arteriole
afferent
arteriole
Glomerular
Filtration
Bowman’s
capsule
glomerulus
Filters blood; proteins can’t pass through
Add ARROWS TO Figure 15-3:
Diagram of a NEPHRON.
Label NEPHRON diagram
1.
2.
3.
4.
5.
6.
7.
8.
9.
Glomerular capsule
Afferent arteriole
Efferent arteriole
Cortical radiate
artery
Cortical radiate vein
Arucate artery
Arcuate vein
Interlobar artery
Interlobar vein
Loop of Henle
(nephron loop)
11. Collecting duct
12. Distal convoluted
tubule
13. Proximal convoluted
tubule
14. Peritubular
capillaries
15. glomerulus
10.
Composition of Glomerular
Filtrate (1,15)
• Water
• Small Soluble Organic
Molecules (i.e. amino acids, glucose)
• Mineral Ions
Proximal Convoluted
Tubule
(13)
Reabsorbs: water, glucose,
amino acids, and sodium.
Loop of Henle
(10)
Descending – reabsorbs H2O
Ascending – reabsorbs Na+ and Cl-
Distal Convoluted Tubule
(12)
ABSORBS - H20
Ca++
PO4 (phosphates)
Na+
SECRETES - H+
K+
Collecting Duct
(11)
Allows for the osmotic
reabsorption of water.
Urine
Water- 95%
Nitrogenous waste:
• urea
• uric acid
• Creatinine (waste product of
muscle cell metabolism)
Ions:
• sodium
• potassium
• sulfate
• phosphate
Urinary Bladder
ureters
external
sphincters
internal
sphincters
Draw
&
label
urethra
Sphincter Muscles on Bladder
Internal urethral sphincter:
• Smooth muscle
• Involuntary control
External Urethral sphincter:
• Skeletal muscle
• Voluntary control
Diuresis
When bladder fills with 200 ml of urine,
stretch receptors transmit impulses to
the CNS and produce a reflex
contraction of the bladder (PNS)
Micturition –
Distension
of the
Urinary
Bladder
voiding;
eliminating urine
Urinalysis
Why do doctors ask for a urine sample?
characteristics:
• smell- ammonia-like
• pH- 4.5-8, ave 6.0
• specific gravity– more than 1.0; ~1.0011.003
• color- affected by what we eat: salty foods,
vitamins
Odor
odor- normal is ammonia-like
diabetes mellitus- smells fruity or
acetone like due to elevated ketone
levels
diabetes insupidus- yucky
asparagus---
pH- range 4.5-8 ave 6.0
vegetarian diet- urine is alkaline
protein rich and wheat diet urine is acidic
Color
Color- pigment is urochrome
Yellow color due to metabolic breakdown of
hemoglobin (by bile or bile pigments)
Beets or rhubarb- might give urine a pink or
smoky color
Vitamins- vitamin C- bright yellow
Infection- cloudy
Abnormal Contents of Urine
Glucose- when present in urine condition
called glycosuria (nonpathological)
[glucose not normally found in urine]
Indicative of:
• Excessive carbohydrate intake
• Stress
• Diabetes mellitus