Urinary system

Question 1

Urinary system

Answer 1

a) Kidneys
b) Urinary tract;
- renal calices
- renal pelvis
- ureters
- urinary bladder
- urethra

*Prod. of urine, thus elimination of waste from body (urea, uric acid, foreign subst…)
*Maintain fluid homeostasis - water og electrolytes
*Prod of hormones og enzymes (Erythropoietin, Renin,
1,25-dihydroxycholecalciferol)

Question 2

Kidney (REN)

Answer 2

12x6x4 cm. 120-170gr. ventrodorsally flattened

• Retroperitoneal
• Frá T12-L2(3)

*right kidney aðeins lower (below liver)

Question 3

Kidneys relations

Answer 3

Posteriorly:

• Diaphragm (sep. kidneys from pleural cavity - costodiaphragmatic recess)
• Psoas major m
• Quadratus lumborum m
• Transversus abdominis m
• 11 og 12 ribs
• Subcostal vessels + nerves
• Iliohypogastric og Ilioinguinal nerves

Anteriorly;
-Right kidney) supraren. gland, liver, desc duodenum, right colic flexure og jejunum

-Left kidney) supraren. gland, stomach, spleen, body pancreas, left colic flexure, jejunum

Question 4

Kidneys, external lýsing

Answer 4

• Ant/Post surfaces
• Sup/Inf extremities
• Medial/Lateral borders (Lateral convex, Medial concave)
• Renal hilum (in middle of medial border)
• -> renal vessels, lymphatics + nerves and renal pelvis enter/leave kidney thru Hilum
• left kidney L1. -right kidney L1-L2
• structures in renal hilum: Renal vein, ant.ramus renal A, renal pelvis og post.ramus renal A.
• Renal sinus; Renal hilum leads into the cavity (renal sinus)
• ->þar er, renal vessels, lymphatics, nerves, renal calices, renal pelvis og perirenal fat.

Question 5

Kidney structure (in frontal section)

Answer 5

1) fibrous capsule; covers ext. surf
2) Cortex: outer pale layer, makes up renal columns á milli renal pyramids

3) Medulla; forms renal pyramids. Bases snúa að cortex, Apices(papillae) að renal sinus.
- Renal papilla með papillary foramina, surrounded by minor calyx

*One Renal lobe= 1 pyramid og adjac. cortex

Question 6

Nephron

Answer 6

a) Renal cortex contains: renal corpsucle, prox+distal tubule og cortical p. of collecting ducts
b) Renal medulla contains; loop of henle og medullary p. of collecting ducts
* Glomerular filtration: water, salts, nutrients og waste moves from glomerulus inn í inside of glom.capsule –>filtrate
* Tubular reabsorption: nutrients og salts actively reabsorbed from prox. conv. tubule into peritubular capillary network. Water flows passively.
* Tubular secretion: Certain molecules are actively secreted from peritubular capillary network into distal conv. tubule
* Reabsorption: of sodium from distal conv. tubule og water from collecting duct (under hormonal control)

Question 6

Nephron

Answer 6

a) Renal cortex contains: renal corpsucle, prox+distal tubule og cortical p. of collecting ducts
b) Renal medulla contains; loop of henle og medullary p. of collecting ducts
* Glomerular filtration: water, salts, nutrients og waste moves from glomerulus inn í inside of glom.capsule –>filtrate
* Tubular reabsorption: nutrients og salts actively reabsorbed from prox. conv. tubule into peritubular capillary network. Water flows passively.
* Tubular secretion: Certain molecules are actively secreted from peritubular capillary network into distal conv. tubule
* Reabsorption: of sodium from distal conv. tubule og water from collecting duct (under hormonal control)

Question 7

Renal fat and fascia

Answer 7

Kidneys are enclosed in fat and fascia

A)Perinephric (perirenal) fat; beint outside fibr. capsule of kidney + inside renal sinus

B)Renal (perirenal) fascia; úr anterior + post. layers

• cranially/laterally, the ant+post layers are fused
• medially/inferiorly, there’s no conn. milli ant+post layers
• renal fascia einnig encloses supraren. glands

C)Paranephric (pararenal) fat; accumulation of fat posteriorly and posterolaterally outside the renal fascia

• kidneys are held in position by
• apposition of neighb organs
• renal fascia + renal vessels

Question 8

kidneys, supply

Answer 8

1) Blood supply og venous drainage;
- right+left renal artery (of abd.aorta)

Renal artery (ant og post ramus)---> Segmental aa
-->Lobar aa --> Interlobar aa

• right+left renal veins, drained into IVC
  2) L. drainage: Lumbar l.nodes

3) Nerve supply; Renal plx
a) symp. fibers (from aortic plx, coeliac gangion and coeliac plx)

b)parasymp. fibers from Vagus n.

C)sensory fibers: from fibr. capsule, thru spinal nerves (segment T10 and T11)

Question 9

Renal segments (respecting branching of the renal A)

Answer 9

1) ant. segment 2)ant. sup. segment 3)ant. inf. segment
4) inf. segment 5)post. segment

Question 10

Renal calices

Answer 10

-Í renal sinus. -take urine to renal pelvis

A)Minor renal calices; 7-14 stk, att. to renal papillae (one calyx to one papilla). Drained into major calices

B)Major renal calices; oftast 3 stk (sup, middle, inf).
Drained into renal pelvis

Question 11

Renal pelvis

Answer 11

External lýsing; funnel-shaped, flattened anteroposteriorly.
G verið dendritic eða ampullar type.

• located in renal sinus, leaving thru renal hilum
• Proj. onto skeleton; L1-L2

*Pelviureteric junction; ca 1/2 length milli renal hilum og inf. pole of kidney

-Relations;
Right renal pelvis; desc duodenum
Left renal pelvis; body pancreas
In both sides; renal vessels

• Blood+nerve supply for renal pelvis og calices
• –> same as kidneys

Question 12

Ureter

Answer 12

-retroperitoneal -run on ant.surf of psoas major
25-30cm long og 3-6mm diameter

parts; 1)abdominal 2)pelvic 3)intramural

Question 13

Constrictions of ureters

Answer 13

1) Pelviureteric juntion
2) Pelvic inlet (crossing w. iliac vessels)
3) Entrance to bladder

*Kidney stones may be get trapped at these constrictions

Question 14

Ureter, abdominal part

Answer 14

Desc. in retroperitoneal space on ant.surf of Psoas major

-Relations:
Genitofemoral n
Gonadal vessels (testicular/ovarian)
Iliac vessels
*On the right; att. of root of mesentery
*On the left; att. of root of sigmoid mesocolon

Question 15

Ureter, pelvic part

Answer 15

Males:

• Internal iliac vessels
• Obturator vessels and nerve
• Deferent duct
• Seminal vesicles

Females:

• Internal iliac vessels
• Obturator vessels and nerve
• Uterine artery* (clinically important; during hysterectomy, ureter has to be identified and isolated from uterine artery)

Question 16

Ureter, supply

Answer 16

Blood supply og venous drainage;

• Renal artery -Testicular/ovarian arteris -A. of def.duct/uterine A
• Sup and Inf vesical aa + corresponding veins

Lymph.drainage into;

• Lumbar l.nodes
• Common iliac l.nodes
• Internal iliac l.nodes

Nerve supply;
symp + parasymp fibers from-->
-Renal plx
-Testicular/ovarian plx
-deferential plx

Sensory fibers;
-thru splanchnic nerves-segments T10-L1

Question 17

Urinary bladder

Answer 17

-capacity; 200-300 ml. Exceptionally 500-750 ml.

Position;

• In lesser pelvis
• empty bladder er subperitoneal (behind pubic symphysis)
• full bladder er preperitoneal (above pubic symphysis, in front of parietal peritoneum/peritoneal cavity, directly behind ant.abd.wall)

Question 18

Urinary bladder, external lýsing og parts

Answer 18

a) Apex; snýr upwards + forwards
* Median umblical ligament (urachus), cont. from it superiorly on ant.abd.wall to the umblicus

b) Body

c) Fundus/base; posteroinferior part
* hér er smooth area–> Trigone (milli openings of ureters+urethra)

d) Neck; surr. origin of urethra. Most inf. part of bladder og most fixed part
(pubovesical lig in female, puboprostatic in male)

Question 19

Urinary bladder, relations

Answer 19

Male;
-Inferiorly: Prostate

-Dorsally; Rectum (rectovesical pouch)
Seminal vesicles and deferent duct (both in rectovesical septum)

• Dorsocranially; Sigmoid colon and Ileum
• Ventrally; Pubic symphysis og retropubic space
• Inferolaterally; Pelvic diaphragm

Female;
-Dorsally; uterus (Vesicouterine pouch, body of uterus) og vagina (Vesicovaginal septum, uterine cervixc + vagina)

• Ventrally; Pubic symphysis og retropubic space
• Inferiorly; pelvic diaphragm

Question 20

Wall of urinary bladder

Answer 20

1) mucous coat (svo submucous layer)

2) muscular coat 3)serous coat

Question 21

wall of bladder: mucous coat

Answer 21

mucous coat=interior of bladder

-mucous membrane loosely att. to muscular coat
(folded in muc. folds that disappear when bladder fills)

*Trigone; er smooth because mucosa is firmly att. to muscular coat. -Í fundus.
Bordered by orifices of ureters (posteriorly) conn. by interureteric crest og urethral orifice (anteriorly)
((In male; orifice is elevated due to middle lobe of prostate
–> uvula)

Question 22

wall of bladder, muscular layer

Answer 22

Smooth muscle that forms:
Detrusor muscle, has 3 layers
(internal-plexiform, middle-circular, outer-longitudinal)

• Internal urethral spinchter–> involuntary, derived from circular layer.
• rectovesical and pubovesical muscles, derived from external layer of muscular coat.
• diff. nerve supply; parasymp. fibers for detrusor
  symp. for spinchter

Question 23

wall of bladder, serous coat

Answer 23

• Peritoneum covers upper+posterior surf of bladder
• Tunica adventitia
• Paracystium; sparse tissue around the bladder

Fixation of the bladder;

• Ventrally; pubovesical ligg. In male also puboprostatic ligg.
• Dorsally; rectovesical ligg in male, vesicouterine ligg in female
• Caudally; to the prostate in male, to the urethra in female
• ->in both to urogenital diaphragm

*Behind the bladder, peritoneum forms pouch;
In male; rectovesical pouch, below it rectovesical septum
In female; vesicouterine pouch, below it vesicovaginal septum

Question 24

Male urethra 18-25cm

Answer 24

- Internal urethral orifice surr. by internal urethral spinchter - External urethral orifice opens on top of the glans of penis (is the narrowest p. of urethra) parts of male urethra: intramural p, prostatic p, membranous p and spongy p

Question 25

parts of male urethra

Answer 25

1) Intramural (preprostatic part); - thru bladder wall, internal urethral spinchter 2) Prostatic part; - widest, fusiform part. - post. wall shows urethral crest and colliculus seminalis w openins of ejaculatory ducts - prostatic ducts open here 3) Membranous part; - shortest, narrowed part - runs thru urogenital diaphragm - external urethral spinchter (derived from fibers from urogenital diaphragm) 4) Spongy part; - within corpus spongiosum of penis -longest part, curved in the subpubic flexure -dilated at its ends (proximally;ampulla, distally;navicular fossa) -ducts of bulbourethral gland open here * Constrictions: 1) ext.urethral orifice. 2)Spongy part. 3)Membr part. 4)Intramural part, * Dilations; 1) navicular fossa. 2)ampulla at onset of spongy part 3) prostatic part.

Question 26

female urethra 2,5-4 cm

Answer 26

-internal urethral orifice surr. by internal urethral sphincter -ext. urethral orifice opens into vaginal vestibule In front of vaginal orifice, on the papillae urethralis - Female urethra desc. downwards og forwards - Then perforates urogenital diaphragm (here surr. by ext. urethral spinchter, derived from urogenital fibers) *Dorsally; Vagina *Ventrally; retropubic space