A&P - Urinary/Renal System

tissue type: perirenal fat capsule

adipose

what portion of the ascending loop of henle is more regulated

thick ascending limb

which limb of the loop of henle can have a thick and thin portion

ascending limb

layers of tissue surrounding kidneys from superficial to deep

renal fascia, perirenal fat capsule, fibrous capsule

tissue type: renal fascia

dense irregular CT

tissue type: fibrous capsule

dense irregular CT

functions of the urinary system

* excretion of waste
* production of hormones
* regulation (blood comp, pH, volume, osmolarity, glucose)

key structures of this system

* kidneys (x2)
* ureter (x2)
* urinary bladder
* urethra

function of transitional epithelium

stretch, change shape, protection

function of simple squamous epithelium

filtration

function of simple cuboidal epithelium

secretion and reabsorption

function of nonkeratinized stratified squamous epithelium

protection from abrasion

function of dense irregular CT

surrounding protection

function of areolar CT

surrounding protection (packing material)

function of adipose CT

surrounding protection

where is smooth muscle found in urinary system

* blood vessels
* ureters
* bladder
* urethra
* internal urethral sphincter

where is skeletal muscle found in urinary system

external urethral sphincter

the urinary system contains mainly ------ muscle and some ----- muscle

smooth; skeletal

smooth or skeletal muscle: blood vessels

smooth

smooth or skeletal muscle: ureters

smooth

smooth or skeletal muscle: bladder

smooth

smooth or skeletal muscle: urethra

smooth

smooth or skeletal muscle: internal urethral sphincter

smooth

smooth or skeletal muscle: external urethral sphincter

skeletal

what nervous system innervates smooth muscle

autonomic NS

what nervous system innervates skeletal muscle

somatic NS

the male urethra is LONGER OR SHORTER than female urethra

longer (20cm>4cm)

how many subdivisions does the male urethra have

3

how many subdivisions does the female urethra have

none

what are the 3 subdivisions of the male urethra

* prostatic
* membranous
* spongy

what extra function does the male urethra have that the female urethra does not

pathway for semen/sperm

what 3 things do the male and female urethra have in common

* location of both the urethral sphincters
* terminal portion of the tract
* major function is excreting urine out of the body

micturition is the process of

emptying the bladder

what nervous system activity contracts the urethral sphincters?

sympathetic NS

micturition reflex: what is the stimulus

increase of bladder volume/increase distention or stretch of bladder wall

micturition reflex: what detects increased distention of bladder

stretch receptors

micturition reflex: what is the integrating center

spinal cord

micturition reflex: what are the two nervous system responses

* increase parasympathetic
* decrease somatic

micturition reflex: responses of increased parasympathetic NS

* relax internal urethral sphincter
* contraction of detrusor (smooth) muscle in bladder wall)

micturition reflex: response of decreased somatic NS

relaxation of external urethral sphincter (voluntary)

micturition reflex: overall response

opening of sphincters, emptying of bladder, urine moves through urethra into external environment

what is the functional unit of the kidney

nephron

how many nephrons are there in each kidney

approximately 1 million

what are the two general parts of the nephron

* renal corpuscle
* renal tubule

parts of the renal corpuscle (of a nephron)

* Bowman’s (glomerular) capsule and space
* glomerulus (glomerular capillaries)

parts of the renal tubule

* proximal convoluted tubule
* loop of Henle
* distal convoluted tubule

what region is bowman’s capsule and space located in the kidney

renal cortex

what region is the glomerulus/glomerular capillaries located in the kidney

renal cortex

what region is the proximal convoluted tubule located in kidney

renal cortex

what region is the loop of Henle located in the kidney

part in renal cortex and descend into medulla

what region is the distal convoluted tubule located in the kidney

renal cortex

cortical or juxtamedullary nephron: makes up the majority of nephrons in body (80-85%)

cortical

cortical or juxtamedullary nephron: renal corpuscle is located in outer cortex

cortical

cortical or juxtamedullary nephron: loops of Henle are shorter and mainly in cortex

cortical

cortical or juxtamedullary nephron: surrounded by peritubular capillaries

cortical

cortical or juxtamedullary nephron: make up the minority of nephrons and are less abundant

juxtamedullary

cortical or juxtamedullary nephron: renal corpuscle is in the inner cortex, farther from the surface

juxtamedullary

cortical or juxtamedullary nephron: loop of Henle is longer and extends deep into medulla

juxtamedullary

cortical or juxtamedullary nephron: surrounded by peritubular capillaries and vasa recta (straight)

juxtamedullary

cortical or juxtamedullary nephron: have thin and thick portions of ascending limb on the loop of Henle

juxtamedullary

cortical or juxtamedullary nephron: important for creating dilute vs concentrated urine

juxtamedullary

3 processes that occur at the nephron

* glomerular filtration
* tubular reabsorption
* tubular secretion

glomerular filtration

* Main goal: create filtrate
* H20 and solutes move from blood plasma into renal tubule and get filtered into the glomerular capsule from glomerular arterioles

tubular reabsorption

* Main goal: move things from filtrate → blood
* H20 and solutes move from tubule back into blood via the peritubular capillaries or vasa recta( in case of juxtamedullary)

tubular secretion

* Main goal: move things from blood → filtrate


* substance not filtered at glomerulus move from blood in the peritubular capillaries and vasa recta into tubule (things we want to excrete that wasn’t filtered)

process of excretion

removal of H20, solutes, and substances from body via urine

excretion equation

excretion = filtration + secretion - reabsorption

when is the fluid in the urinary system BLOOD

* afferent arteriole
* efferent arterioles
* filtered at glomerulus (glomerular cap) and bowman’s capsule

what is the glomerulus refer to

bundle of glomerular capillaries in the renal corpuscle

tissue type: afferent artierioles

simple squamous

tissue type: efferent arterioles

simple squmous

tissue type: glomerulus/glomerular capillaries

simple squamous

tissue type: bowman’s capsule and space

simple squamous

when is the fluid in the urinary system FILTRATE

* after bowmans capsule and in the proximal convoluted tubule
* descending limb
* ascending limb
* distal convoluted tubule
* collecting duct
* papillary duct

when is the fluid in the urinary system URINE

after the papillary duct and beginning of minor calyx and out

tissue type: proximal convoluted tubule

simple cuboidal epi (increases surface area for reabsorption)

tissue type: descending limb of loop of henle

simple squamous epi (water reabsorption)

tissue type: thin ascending limb of loop of henle

simple squamous epi (solute secretion or reabsorption less regulated)

tissue type: thick ascending limb of loop of henle

simple cuboidal (solute secretion or reabsorption more regulated)

tissue type: distal convoluted tubule

simple cuboidal (water/solute reabsorption and solute secretion)

tissue type: collecting duct

simple cuboidal (water/solute reabsorption and solute secretion)

tissue type: papillary duct

simple columnar (some secretion and reabsorption)

tissue type: minor calyx

transitional epi (can’t change fluid/blood concentration anymore)

tissue type: major calyx

transitional epi

tissue type: renal pelvis

transitional epi

tissue type: ureter

transitional epi & smooth muscle

tissue type: urinary bladder

transitional epi

tissue type: urethral

smooth muscle (ex. sphincter skeletal)

transitional and nonkeratinized stratified squamous more externally

oxygenated blood flow from left ventricle to efferent arterioles

* aorta
* abdominal aorta
* renal arteries
* segmental arteries
* interlobar arteries
* arcuate arteries
* interlobular arteries
* afferent arterioles
* glomerular capillaries → nephron
* efferent arterioles

capillary blood flow from efferent to venous circulation

* efferent arterioles (oxy blood) to either
* peritubular capillaries
* vasa recta (juxtamedullary)
* interlobular veins (deoxy blood)

venous, deoxygenated blood flow from interlobular veins to right atrium

* interlobular veins
* arcuate veins
* interlobar veins
* renal veins
* inferior vena cava
* right atrium

filtrate flow from glomerular capillaries to papillary duct

* glomerular capillaries (filtering blood
* bowman’s capsule/space
* proximal convoluted tubule
* loop of henle
* distal convoluted tubule
* collecting duct
* papillary duct

urine flow from minor calyx to external environment

* minor calyx
* major calyx
* renal pelvis
* ureter
* urinary bladder
* urethra
* male: prostatic, membranous, spongy
* external environment

filtration definition

blood in glomerular capillaries moving across the filtration membrane to become filtrate in renal tubule

how much fluid is reabsorbed back into blood

99%

how much fluid is actually excreted/day

1-2L

what is allowed through the filtration membrane and enter bowman’s capsule/space

water and small solutes allowed through

what is NOT allowed through the filtration membrane and will flow out in the efferent artierioles

proteins and blood cells are not allowed through

3 barriers of filtration membrane

* glomerular endothelial cells with fenestrations
* basement membrane
* podocytes

glomerular endothelial cells are ---- leaky than normal blood capillaries and allow things to pass through besides blood cells

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