I.
II.
BODY STRUCTURE AND FUNCTION
URINARY SYSTEM LESSON PLAN
By Francine T. Russell RN BSN MA
January 2008
URINARY SYSTEM
A.
Structures and Functions
Instruct students to place hands at waist at lumbar region with right hand
slightly lower than left – kidneys location.
Draw the system labeling each structure and have students draw and label
in notes using different colored pencils/markers.
1.
kidneys (2)
a.
excretes toxins and nitrogenous wastes
b.
regulates levels of many chemicals in blood
c.
maintains water balance
d.
helps regulate blood pressure by secretion of hormone renin
2.
ureters (2)
a.
pathways for urine drainage from kidneys to bladder
3.
bladder (1)
a.
storage unit for urine before urination
b.
urination
4.
urethra (1)
a.
pathway for urine from bladder to outside body
b.
opening of urethra to exterior through meatus
KIDNEY
A.
Draw a kidney and identify/label structures within. Instruct students to
draw and label same in notes using different colored pencils/markers.
1.
cortex – outer portion
2.
medulla – inner portion
3.
pyramid – triangular shapes
4.
papilla – narrow inner portion at pelvis
5.
renal pelvis – larger upper part of ureter
6.
calyces – segments of renal pelvis for pathway of urine from
pyramid
7.
renal columns – areas in medulla between each pyramid
B.
Draw a nephron and identify/label structures within. Instruct
students to draw and label same in notes using different colored
pencils/markers.
1.
Renal Corpuscle
a.
Bowman’s capsule – cup shaped cap surrounding
glomerulus
b.
Glomerulus – network of blood capillaries inside Bowman’s
capsule
2.
Renal Convoluted Tubules
a.
Proximal Convoluted Tubule – first segment after Bowman’s
capsule
b.
Loop of Henle – extension of tubule extending into the
medulla
1.
descending loop
2.
loop
3.
ascending loop
c.
Distal Convoluted Tubule – segment following Loop of Henle
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d.
Collecting tubule – last segment
Arterioles
a.
Afferent
1.
Carries blood from renal artery to glomerulus
2.
Larger due to pressure of blood sent to kidneys
b.
Efferent
1.
Carries blood from glomerulus and surrounds
convoluted tubule
4.
Juxtaglomerular apparatus
C.
Explain formation of urine using drawing of nephron, label each process
where it occurs and the substances involved. Instruct students to label their
nephron drawing with different colored pencils/markers.
1.
Filtration
a.
water and dissolved substances from glomerulus are filtered
out of the blood and enter tubule
2.
Reabsorption
a.
water, glucose and sodium are reabsorbed from
tubule into efferent arteriole
3.
Secretion
a.
ammonia, K+, hydrogen ions and some drugs are
secreted from efferent arteriole into distal tubule
D.
Explain control of urine volume
1.
ADH secretion (water retaining hormone)
a.
secreted from posterior pituitary
b.
signals collecting tubule to reabsorb more water, producing
less urine
2.
Aldosterone secretion (water and sodium retaining hormone)
a.
secreted from adrenal cortex
b.
signals tubules to reabsorb sodium quicker into the efferent
arteriole
3.
ANH (water and sodium losing hormone)
a.
secreted from atria of heart
b.
signals tubules to secrete more sodium and more water
URETERS
A.
Draw and label the parts of the ureter. Instruct students to draw and label
same in notes using different colored pencils/markers.
B.
Explain size of ureter – ¼” wide x 10-12” long
C.
Explain peristalsis
URINARY BLADDER
A.
Draw and label the parts of the urinary bladder. Instruct students to draw
and label the bladder in notes using different colored pencils/markers.
1.
trigone – triangle shaped area between posterior entrance of ureters
and neck of bladder
2.
rugae – rough, wrinkled surface of remaining interior bladder when
bladder is empty – smooth when distended
URETHRA
A.
Draw and label the urethra for the female and another for the male, noting
the prostate surrounding the urethra in the male. Instruct students to draw
and label the urethra in notes using different colored pencils/markers.
B.
Explain the lining of the urinary system and its role in infection
3.
II.
III.
IV.
2
1.
Same mucous membrane lines the renal pelvis, ureters, bladder and
urethra allowing microbes that enter the urethra to progress all the
way up to the kidneys
C.
Explain the difference between the male and female urethra
1.
female – 1½” long
2.
male – 8” long
a.
surrounded by prostate gland
b.
serves two purposes
1.
terminal end of urinary tract
2.
pathway for movement of reproductive fluid from
body
V.
MICTURITION
A.
Micturition, urination, voiding – mean emptying urinary bladder of urine
B.
Two sphincters control urination
1.
Internal urethral sphincter
a.
at bladder exit
b.
involuntary control
2.
External urethral sphincter
a.
below the neck of the bladder
b.
voluntary control
C.
Emptying reflex
1.
Pressure felt at 300 – 400 ml urine in bladder
2.
With bladder stretching, nervous impulses are sent to 2nd, 3rd
and 4th sacral nerves to initial emptying reflex
a.
bladder muscles contract, forcing relaxation of internal
sphincter and urine enters the urethra
D.
Voiding
1.
Voluntary contraction of external sphincter permits urine to empty
from urethra to outside
E.
Difficulty with urination
1.
Retention – urine production is normal but person unable to void
2.
Suppression – no urine production but bladder mechanism is normal
3.
Incontinence – unable to control urine elimination
4.
Cystitis – bladder infection
5.
Overactive bladder – person feels extreme urgency to void and
voids in small amounts with pain
VI.
DIALYSIS
A.
Process that artificially cleanses the blood via a machine used for
people whose kidneys no longer function or function poorly D/T
disease, illness, etc.
1.
Hemodialysis – removes wastes via a machine
2.
CAPD (continuous ambulatory peritoneal dialysis) – dialysis fluid is
infused into the peritoneal cavity through an opening in the
abdominal wall and then drained off in a few hours, eliminating
waste products and then new dialysis fluid is again infused to repeat
the process
VII.
AGING KIDNEYS
A.
Adults begin to lose nephron function beginning at age 35
VIII. LITHOTRIPSY
A.
Process that utilizes a lithotriptor using ultrasound waves to break up
kidney stones for easier, less painful elimination from the urinary system
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IX.
CHARACTERISTICS OF URINE
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