Urinary System

Question 1

urinary system consists of…

Answer 1

2 kidneys
2 ureters
1 urinary bladder
1 urethra

Question 2

urinary system functions

Answer 2

• regulate blood volume, blood pressure, pH + ion concentration
• eliminate urea, uric acid, drugs etc.

Question 3

kidney characteristics

Answer 3

• retroperitoneal located behind peritoneum b/w dorsal body + parietal peritoneum
• hilus is medial indentation
• contains renal artery, renal vein + ureter
• right kidney is slightly lower due to liver
• protected by renal capsule (adipose tissue + renal fascia)

Question 4

kidney: internal gross anatomy

Answer 4

1) renal cortex

2) renal medulla: contains renal pyramids

Question 5

renal medulla: renal pyramids

Answer 5

• separated by renal columns (downward extensions of cortical tissue)
• 6 renal columns per kidney
• narrow end call apex of renal papilla

Question 6

kidney characteristics

Answer 6

• retroperitoneal
• contains renal artery, renal vein + ureter
• protected by renal capsule

Question 7

renal capsule is made of…

Answer 7

adipose tissue + renal fascia

Question 8

kidney location

Answer 8

behind peritoneum b/w dorsal body + parietal peritoneum

Question 9

KIDNEY: internal gross anatomy

Answer 9

1) renal cortex

2) renal medulla: renal pyramids

Question 10

renal pyramids

Answer 10

• separated by renal columns
• narrow end = apex
• collecting ducts exit at renal papillary

Question 11

flow of collecting ducts in renal medulla

Answer 11

material > 4-5 minor calyces > 2-3 major calyces > renal pelvis > ureter

Question 12

KIDNEY: microscopic anatomy

Answer 12

1) nephron

2) renal corpuscle

Question 13

nephrons: cortical nephron

Answer 13

• 85% of nephrons
• renal corpuscle located near surface in cortex
• loop of henle is shorter & located in outer medulla
• composed of peritubular capillaries

Question 14

nephrons: juxtamedullary nephrons

Answer 14

• 15% of nephrons
• renal corpuscles in cortex are close to medulla
• very long loops of henle penetrate deep into medulla
• contain peritubular capillaries + vasa recta
• allow concentration + dilution of urine

Question 15

blood supply to kidney

Answer 15

renal arteries > segmental arteries > interlobular artery (delivers blood up columns) > arcuate artery (junction of medulla + cortex) > cortical arteries

Question 16

blood supply to nephrons

Answer 16

cortical radiate artery > afferent arteriole > glomerulus > efferent arteriole > peritubular capillaries (cortical nephrons + vasa recta in juxtamedullary nephrons) > cortical radiate vein > arcuate vein > interlobular vein > renal vein

Question 17

juxtamedullary apparatus

Answer 17

• located at point of contact b/w distal convoluted tubule + afferent arteriole
• function: regulate blood pressure, ion concentration of blood + formation of filtrate

Question 18

juxtamedullary apparatus: tubular portion

Answer 18

• macula densa
• composed of modified cells of distal convoluted tubule
• cells are taller + narrower

Question 19

juxtamedullary apparatus: arteriolar portion

Answer 19

• composed of afferent + efferent arteriole
• juxtaglomerular cells (modified smooth muscle cells contain granules)
• produce hormonal enzyme - renin

Question 20

ureters

Answer 20

• retroperitoneal
• function: transport new formed urine from kidneys

1. mucosa: transitional epithelium (allows stretching)
2. muscularis externa: smooth muscle
3. serosa/advetitia

Question 21

urinary bladder

Answer 21

• mainly retroperitoneal

1. mucosa: transitional + rugae (folds of epithelium)
2. muscularis externa: smooth muscle - detrusor muscle
3. adventitia: posterior + inferior surfaces, superior surface is serosa

Question 22

urinary bladder: internal structure

Answer 22

trigone: triangle from opening of 2 ureters + urethra
- lacks rugae
- openings are fixed

Question 23

urethra basic charateristics

Answer 23

• connects bladder to outside
• male: longer and transports urine + semen
• female: short and only urine

Question 24

urethra: sphincters

Answer 24

• internal is thickening of detrusor muscle at base of bladder (smooth muscle)
• external surrounds urethra passing thru urogenital diaphragm (skeletal muscle)
• both sphincters surround proximal opening

Question 25

wall of urethra

Answer 25

• smooth muscle lined by mucosa (transitional proximal to bladder)
• stratified squamous near end of urethra

Question 26

MICROSCOPIC ANATOMY: nephron

Answer 26

functional unit made of renal corpuscle + renal tubule

Question 27

MICROSCOPIC ANATOMY: renal corpuscle

Answer 27

• in renal cortex
• site for blood filtration
• made of glomerulus (capillary bed) + bowman’s capsule (encases + drains filtrate into proximal convoluted tubule)

Question 28

KIDNEY: filtration membrane

Answer 28

• consists of Bowman’s capsule + glomerulus
• filters into Bowman’s capsule
• consists of: glomerular endothelium, basement membranes, podocyte of Bowman’s capsule

Question 29

glomerular endothelium

Answer 29

porous epithelial layer of simple squamous cells

Question 30

basement membrane

Answer 30

attach glomerular endothelium to podocytes

Question 31

podocytes of Bowman’s capsule

Answer 31

• simple epithelium (allows filtrate to pass)

- made of podocytes w/ filtration slits

Question 32

KIDNEY: renal tubule consists of

Answer 32

1) proximal convoluted tubule
2) loop of henle
3) distal convoluted tubule

Question 33

proximal convoluted tubule (PCT)

Answer 33

in cortex of kidney

Question 34

loop of henle

Answer 34

descending > ascending look of henle in medulla

Question 35

distal convoluted tubule (DCT)

Answer 35

in cortex of kidney