Exam 2: Urinary System Flashcards
What are all the organs included in the Urinary system?
- Kidneys (2)
- Ureters (2)
- Urinary Bladder (1)
- Urethra (1)
What are the 4 general functions of the kidney?
- regulate water and electrolyte balance
- excretion of nitrogenous wastes and some water and electrolytes
- excretion of some other materials (i.e. drugs)
- secrete renin
What are the 6 general parts of the kidney?
- Capsule
- Hilum
- Renal pelvis
- major calyces
- minor calyces
- renal sinus
What is the capsule of the kidney made of?
dense irregular CT
it is thin and fibrous
What is the hilum of the kidney?
is concave and medial Where: - nerves in - ureters exit - blood and lymph enter and exit
What is the widening of the ureter called?
renal pelvis
What are the broad spaces w/in the kidney to collect urine and direct to renal pelvis? How many are there per kidney?
major calyces, 2-3 per kidney
What are the smaller collecting areas from each major calyx? What do they contain?
minor calyces–> contain renal papilla = tip of each renal pyramid
What is the area surrounding the pelvis, major calyces, and minor calyces? What does it contain?
renal sinus; contains adipose
What are the two general regions of the parenchyma within the kidney?
- Cortex
2. Medulla
What three things does the Cortex of the kidney contain?
- Renal corpuscles
- Tubules
- Medullary Rays
What do the medullary rays of the cortex of the kidney extend from? What do they contain?
extend from medulla into cortex
contain primarily portions of the Loop of Henle and collecting tubules
What does the medulla region of the kidney contain?
- Renal pyramids
2. Renal columns
How many renal pyramids are in each kidney?
8-12/kidney (in medulla)
has parallel nephrons and collecting ducts
What are the areas separating the renal pyramids in the kidney? What does it contain?
renal columns (found in renal medulla) Has: - blood vessels, - urinary tubes, and - fibrous CT
How many nephrons does each kidney contain?
~ 1 million
What are the 5 parts of a nephron and in order from where capillaries first interact with it?
- Renal Corpuscle
- Proximal Convoluted Tubules (PCT)
- Loop of Henle
- Distal Convoluted Tubule (DCT)
- Connecting Tubule
Where is the renal corpuscle located?
always in the cortex
What is the general function of the renal corpuscle?
blood filtration
What are the 3 parts of a renal corpuscle?
- Bowman’s (glomerular) capsule
- Glomerulus
- Mesangial Cells
How many layers does the Bowman’s Capsule have and what are they?
(found in Renal Corpuscle)
- Parietal Layer
- Visceral Layer
What type of epithelium is the parietal layer of the Bowman’s Capsule made of?
simple squamous epithelium
Where in the nephron are podocytes found?
in Visceral layer of Bowman’s capsule, part of the Renal corpuscle
What is the visceral layer of the Bowman’s Capsule mad of?
internal layer of podocytes
What are modified epithelial cells contain pedicels?
podocytes (in Visceral layer of Bowman’s Capsule)
What are the secondary podocyte cell processes covering the glomerular capillaries and creating filtration slits?
pedicels (in visceral layer of Bowman’s Capsule)
What is the space between the parietal and visceral layers of the Bowman’s capsule?
Urinary (capsular) space
What does the Urinary (capsular) space receive?
(part of the renal corpuscle)
receives the filtrated fluid from capillaries
What is the fenestrated capillary network inside the visceral layer of Bowman Capsule called?
Glomerulus (is a “tuft of capillaries”)
What type of basement membrane does the glomerulus have?
a thick basement membrane
What is the function of the glomerulus?
blocks large proteins
What makes the glomerulus unique about its placement?
located b/w 2 arterioles so muscle in tunica media can create an increased capillary pressure to enhance filtration
(contraction will increase filtration)
What are the special cells found w/in the renal corpuscles and are thought to replace regular CT cells?
Mesangial cells (are pericyte-like)
Where are Mesangial cells often present?
in areas lacking podocytes (all w/in the renal corpuscle)
What are the functions of Mesangial cells?
- structural support (of capillaries)
- adjust capillary pressure for good filtration
- phagocytosis of interfering materials
What are the first set of tubules after the renal corpuscle?
Proximal convoluted tubules (PCT)
What type of epithelium as the proximal convoluted tubules made of?
simple cuboidal with many long microvilli
Where are the proximal convoluted tubules located?
cortex of the kidney
What comes after the proximal convoluted tubules?
Loop of Henle (4 parts)
What are the four parts of the Loop of Henle?
- Proximal straight tubule
- thin descending limb
- thin ascending limb
- thick ascending limb
What type of epithelium is the proximal straight tubule made of?
simple cuboidal (NO microvilli)
Where is the proximal straight tubule located?
medulla of the kidney
What type of epithelium are the thin descending and ascending limbs made of?
simple squamous
Where are the thin descending and ascending limbs of the kidney located?
medulla of the kidney
What type of epithelium are the thick ascending limbs made up of?
simple cudoidal (NO microvilli)
Where are the thick ascending limbs located?
medulla and medullary rays of the kidney
What type of epithelium are the distal convoluted tubules made of?
simple cuboidal (shorter cells with fewer and shorter microvilli)
Where are the distal convoluted tubules located?
cortex of the kidney (close to renal corpuscle)
What is a special part of distal convoluted tubules at the vascular pole that contain closely packed columnar cells? What apparatus is this a part of?
Macula densa; a part of juxtaglomerular apparatus (JGA)
What type of cells does the Macula densa, a special part of distal convoluted tubules at the vascular pole, contain?
closely packed columnar cells
What are the three parts of the Juxtaglomerular apparatus (JGA)?
- macula densa
- juxtaglomerular granular cells = smooth ms. cells in afferent arterioles
- lacis cells = extraglomerular mesangial cells
What type of epithelium are connecting tubules made of?
simple squamous to simple cuboidal
T/F. The collecting ducts are the last part to be considered a part of the nephron.
False– the “connecting tubule” is the last part of the nephron
What type of epithelium are the collecting ducts made of?
simple cuboidal to simple columnar (in larger ducts)
What are the two cell types found in collecting ducts?
- Principle cells = light cells = collecting duct cells
2. Intercalated cells = dark cells
What are the MC cell type in the collecting ducts?
principle cells (or light cells or collecting duct cells)
Where are the Principle cells associated with the collecting ducts located in the kidney?
medullary rays and medulla
Are intercalated cells or principle cells more abundant in the Collecting ducts?
principle cells
intercalated cells are fewer in number
Where are they intercalated cells ass. with the collecting ducts located?
medullary rays
Where do the collecting ducts lead to? What will that lead to? And finally what will that lead to?
collecting ducts–> papillary duct–> renal papillae–> minor calyx–> (ureter)
What are the major Luminal Wall layers, in general?
- Mucosa (epithelium, lamina propria, muscularis mucosae)
- Submucosa
- Muscularis externa (ME)
- Adventitia
~Serosa = squamous cells w/ lubrication fxn outside of ME
What are the three sublayers of the Mucosa and what do they contain?
- Epithelium–> varies based on organ fxn
- Lamina propria–> loose CT w/ small blood vessels; lymphatics, nerves, ~glands; supports epithelium
- Muscularis mucosae–> longitudinal arranged smooth ms.; discont,; provides strength; thickness varies
What does the “normal” Submucosa layer contain?
- more fibrous CT
- provides strength
- larger blood vessels
- glands possble
What does the Muscularis Externa layer consist of? What the normal pattern considered?
- sig. muscle layer
- USUALLY smooth ms.
Normal Pattern: inner circular and outer longitudinal
Describe the “normal” Adventitia layer?
CT on outside of muscularis externa; has a binding function*
What is the serosa associated with luminal wall layers?
(= visceral peritoneum when below diaphragm)
- an edge of squamous cells outside the Muscularis Externa; can secrete serous fluid and has a lubrication function*
What is the function of Ureters?
to transport urine to urinary bladder
2 of them, ~24-34cm long
What is the surface epithelium for the Mucosa luminal wall layer of the ureters?
urothelium (has 3 basic layers)
~4-5 cell layers thick
What are the 3 basic layers of the surface epithelium of the Mucosa luminal wall layer of a Ureter?
- one layer of basal cells
- one to several layers of intermediate cells (more columnar shape)
- one layer of large superficial cells (can be bi-nucleate)
Within the Mucosa layer of the Ureter, describe the Lamina propria.
rather dense irregular CT
normal pattern is loose CT
Describe the Submucosa layer of the Ureter.
blends with lamina propria
Describe the Muscularis Externa layer of the Ureter
smooth ms mixed w/ CT
REVERSE PATTERN–> inner longitudinal and outer circular
Distal end has 3 muscle layers
What happens at the distal end of the Muscularis Externa layer in the ureters?
Has 3 Muscle Layers:
- inner longitudinal
- middle circular
- outer longitudinal
T/F. Peristaltic contraction helps move the urine in the ureters.
True
What does the Adventitia layer of the ureters contain?
adipose, blood vessels, and nerves
Hows does the ureter connect to the bladder? why?
enters at an angle to create a valve–> as bladder fills entrance to ureters is closed
What is the function of the valve that is created due to the way the ureters connect to the bladder? Why is this important?
prevent backflow of urine into ureters
important to stop the spread of infection to the kidneys
What is the function of the urinary bladder?
to store urine
Does the ureter or urinary bladder have a muscularis mucosae w/in their mucosa layers?
NOPE
What type of epithelium is the mucosa layer of the urinary bladder>
transtitional/ urothelium
What is the function of the epithelium in the mucosa of the urinary bladder?
(transitonal/urothelium)
to stretch and protect from hypertonic and toxic urine
What are unique characteristics of the epithelium of the mucosa layer in the urinary bladder?
(transitional/urothelium)
- usually 6+ layers thick
- Umbrella cells–> one layer of large superficial cells (can be bi-nucleated)
- *Plaque develops on free edge of epithelial plasma membrane
Where is the unique feature of plaque located in the urinary system? What is its function?
in transtional/urothelium epithelium layer of mucosa in BLADDER
–has thick and thin areas so can fold at thinner areas when bladder collapses
Functions:
1. protection of cells with tissues beneath
2. to block water passage (out of living tissue)
Describe the Lamina propria of the urinary bladder.
dense irregular CT
same as Ureter
Describe the Submucosa of the urinary bladder.
thin and blends with lamina propria
Is the muscularis externa of the urinary bladder “normal pattern” or different?
has 3 indistinct smooth ms layers = Detrusor Muscle
- inner longitudinal
- middle circular
- outer longitudinal
~Internal Urethral Sphincter
What are three notes about the Internal Urethral Sphincter?
- circle of smooth muscle close to urethral opening
- part of detrusor muscle
- involuntary sphincter
Does the urinary bladder have an Adventitia layer?
yes (doesn’t follow her “rule of thumb” that vertical organs only have Adventitia)
What is the sympathetic innervation to the urinary bladder go to?
blood vessels
Where do the parasympathetics innervating the urinary bladder come from and where are they going to?
from S2 to S4 via Splanchnic nerves
–> go to Muscularis Externus and Adventitia
What is the function of the parasympathetic innervation to the urinary bladder?
micturition reflex
Where does the sensory innervation of the urinary bladder go to? What is their function?
urinary bladder –> to sacral spinal cord
Fxn: afferent fibers for micturation reflex
What type of “tube” is the urethra and what kind of folds does it have in mucosa?
fibromuscular tube
longitudinal folds in mucosa
What systems is the male urethra a part of? What about the female urethra?
Male–> part of urinary and reproductive system
Females–> only part of urinary system
What are the three sections of the Urethra in males?
- Prostatic urethra (~3-4cm)
- Membranous urethra (~1cm)
- Spongy (Penile) urethra (~15cm)
What type of surface epithelium does the Prostatic urethra contain? where is it located?
located in prostate
urothelium
Where does the membranous urethra of males pass through?
the external urethral sphincter–> which is skeletal muscle (under VOLUNTARY control)
What type of surface epithelium is the Membranous urethra of males made of?
stratified columnar and pseudostratified columnar
What is the Spongy (Penile) urethra surrounded by?
erectile tissue (corpus spongiosum)
What is the surface epithelium of the Spongy (Penile) Urethra?
stratified columnar and pseudostratified columnar
distally–> stratified squamous
How long is the urethra in females and what system(s) is it a part of?
4-5cm long; urinary system ONLY
What is the surface epithelium of the urethra in females?
First part–> transitional
Middle part–> stratified columnar/pseudostratified columnar
Distally–> stratified squamous
What portion of the female urethra is the external urethral sphincter around?
middle portion (stratified columnar/pseudostratified columnar)
