A&PII Renal

diffusion is _______ process where solutes move across a permeable membrane from _____ concentration to ______ concentration
passive ; higher ; lower
osmosis describes the movement of this
water moves from an area of ______ solute concentration to _____ solute concentration
lower ; higher
most solutes in body fluids are
Na+ K+ Cl-
formed elements in the blood
a large plasma protein
Average male GFR
125 ml/min
Average female GFR
105 ml/min
if GFR is too high
useful substances excreted in the urine
if GFR is too low
certain waste products may not be adequately excreted
when does the process of reabsorption begin
when the filtrate enters the renal tubules
where does most reabsorption occur
proximal nephron
where does fine tuning of fluid and electrolytes occur
distal nephron
destiny of most peritubular secretions
excreted in urine
renal tubules consist of
single epithelial cell layer
peritubular capillaries /vesa recta single endothelial cell layer
single cell layer of membranes
enhances solute transport
most important mechanism for solute exchange between the blood and interstial fluid
transport mechanism for large lipid-insoluble molecules
transcytosis uses these to enter endothelial cells
pinocytic vesicles
bulk flow descibes the passive movement of
large numbers of ions
bulk flow occurs from ____ pressure to ____ pressure
high to low
these cells secrete ANP
cardiac myocytes (right atrium)
ANP is released in response to
increased blood volume
ANP ____afferent arterioles
ANP _____ efferent arteriole
when GBHP increses
GFR increases
an increased GFR _____ Na+ and water excretion
an increased GFR ____ blood volume
angiotensin II is a very potent
systemic vasoconstrictor
angiotensin II ______ glomerular mesangial cells
DLOH is impermiable to
DLOH plays a role in
urine concentration
in early DCT ______ is transported into tubule cells
Na+ and Cl-
blood hydrostatic pressure BHP
pressure generated by the pumping action of the heart
interstitial fluid osmotic pressure IFOP
pressure exerted by the presence of small proteins in interstitial fluid
IFOP is usually
low ~1mmHg
which pressures promote filtration
which pressures promote reabsoption
blood colloid osmotic pressure BCOP
pressure exerted by colloidal suspension of large plasma proteins
interstitial fluid hydrostatic pressure IFHP
normally very low
IFHP is usually
very low ~0mmHg
net filtration pressure NFP
the balance of all 4 pressures that determines if the blood volume and interstitial fluid changes or remains steady
calculate NFP
Ffiltration reabsorption
Starling's law of the capillaries
explains the near equilibrium between the fluid and solutes in the plasma and the interstitial fluid
in normal bulk flow _______ of the fluid filtered out of the capillaries at the arteriolar end is reabsorbed into the venule end
most (85%)
20 liters of fluid is filtered and ____ is reabsorbed
17 L
where does the excess filterd fluid within the interstital (3L) go
enters the lymphatic capillaries and returned to blood circulation (via thoracic duct)
body water loss > body water gain
decrease in body water volume will
decrease arterial blood pressure
if arterial blood pressure decreases what is activated
RAAS renin-angiotensin-aldosterone-system
an increase in body water osmolarity is detected in
osmoreceptors in the hypothalamus
what stimulates thirst
hypothalamus osmoreceptors
the main factor determining body fluid volume
urinary NaCl loss
the main factor determining body fluid osmolarity
urinary water loss
kidney functions
reg blood pH
reg fluid/electrolyte balance: bp & blood volume
excretion of metabolic waste products
hormone production (renin, erythropoietin)
vitD (calcitriol) production for Ca homeostasis
ammoniagenesis (increases when acidotic-help H+ buffering)
where are the kidneys located
what ribs protect the kidneys
11th & 12th
which kidney is more superior?
the left kidney
which kidney is more inferior? why
the right kidney b/c of the liver
what is the function of the renal hilum
blood, lymph vessels, ureters, and nerves enter/exit here
if you decrease the GFR, you get
sodium reabsorption
an increase in sodium reabsorption leads to
an increase in blood volume
where does renin come from
JG cells
if it comes out of JG cells it goes to
afferent arterioles
what makes up the JG apparatus
JG cell + macula densa cells
is angiotensin I or II a greater vasoconstrictor
II > I
in the DCT aldosterone stimulates _______ retention
sodium and water
in the DCTaldosterone stimulates ______ secretion
potassium and hydrogen (ions)
where does ANP come from
cardiac myocytes
ANP opposes the actions of
angiotensin II
ANP leads to an increase in
when GFR increases sodium reabsorption ____
is inhibited
natriuresis and diuresis leads to
decreased ECF volume
where does urodilantin come from; where is it secreted
renal tubules
what is urodilantin
a naturietic peptide related to ANP
what does urodilantin do
decreases sodium reabsorption in the collecting ducts
when do HCO3/Cl antiporters function
only during alkalosis
what cells have the ability to secrete HCO3 into the filtrate during alkalosis
beta intercalated cells
what cells secrete H+
alpha intercalated cells
Na+ - (Cl- + HCO3-)
anion gap
anion gap is used to differentiate between
uncompensated metabolic acidosis caused by acid gain or bicaeb loss
where does bicarb loss commonly occur
lower GI tract
every time you loss bicarb, what do you gain
the renal fascia is
the most superficial layer surrounding the kidney
what does the renal fascia do
anchors the kidney to the abdominal wall & surrounding structure
what hormones does the kidney make
where is the adipose capsule
deep to the renal fascia
what does the adipose capsule do
its a fatty tissue layed that protects and firmly holds the kidney in place
what is the deepest layer surrounding the kidney
renal capsule
what does the renal capsule do
maintains the shape of the kidney & serves as a barrier against trauma
external kidney tissue layers deepest to most superficial
renal capsule, adipose capsule, renal fascia
external kidney tissue layers superficial to deep
renal fascia, adipose capsule, renal capsule
the kidneys are innervated by ______ division nerve fibers
renal nerves are mostly ______ nerve
what is the main function of renal nerves
regulate blood flow through the kidneys
_____ mechanisms insure adequate blood flow & glomerular filtration during resting/tonic SNS input
resting GFR must increase efferent arterioles will ______ while afferent arteriole _______
constrict ; vasodialte
internal anatomy of the kidney
cortex, medulla, renal lobes, minor calyces, major calyces, renal pelvis, renal sinuses, nephrons
where is the renal cortex
renal capsule to the base of the pyramids
the cortex between the pyramids is know as
renal columns
how many renal pyramids make up the medulla
the apex of the pyramids is also known as
renal papilla
what does the base of each pyramid contact
the cortex
what makes up a renal lobe
single pyramid
overlying area of renal cortex
1/2 of each adjacent renal column
what does the minor calyces do
receives urine from the papillary ducts of 1 renal papilla and delivers it to a major calyces
what does the major calyces do
recieves urine from the minor calyces
how many major calyces does each kidney have
the renal pelvis
receives urine from the major calyces
the ureter
transports urine from the renal pelvis top the bladder
3 anatomical regions of the male urethra
spongy (penile)
the male urethra passes through
the prostate
deep perineal muscles
length of the male urethra
length of female urethra
where is the female external urtheral orifice
between the clitoris and vaginal opening
what is the urethra
a small tube leading leading from the internal urethral sphincter (in the bladder floor) to the outside
for the discharge of urine
urination or voiding
where is the micturition reflex center
sacral spinal cord
what action does the parasympathetic nervous system (ACh) have on the bladder
contration of the detrusor and relaxtion of the sphincter
how much urine volume in the bladder is required to stimulate the stretch receptors
which comes 1st bladder filling or the micturition reflex
bladder filling, it causes a sensation of fullness that initiates a conscious desire to to urinate (before micturition reflex occurs)
tissue layers of the ureters, deepest to superficial
mucosa, muscularis, adventitia
tissue layers of the ureters superficial to deep
adventitia, muscularis, mucosa
what do the ureters have at the distal (1/3) end
extra layer of longitudinal muscle fibers
why do the ureters have a muscular layer
the mucosa layer of the ureters is made up of
goblet cells
what is the function of ureteral goblet cells
secrete mucoius to protect the epithelial cells from acidic urine
what is the function of the ureteral adventitia
anchor the ureters in place in the abdominal cavity
where is the urinary bladder in males
anterior to the rectum
where is the urinary bladder in females
anterior to the vagina and inferior to the uterus
what holds the bladder in place
peritoneal folds
small triangular area in the bladder floor
posterior corners - urteral ostia
anterior - internal urethral orifice
generally where does the unrinary bladder
pelvic cavity posterior to the pubic symphysis
wall layers of the bladder deep to superficial
mucosa, detrusor muscle, adventitia (posterior/inferior) and serosa (superior)
wall layers of the bladder superficial to deep
serosa (superior, adventitia (posterior/inferior), detrusor muscle, mucosa
what is the external sphincter muscle made of
voluntary skeletal muscle
the internal urethral sphincter is made of
circular detrusor muscle fibers
where is the internal urethral sphincter
surrounding the opening to the urethra
where is the external sphincter muscle
inferior to the internal urethral sphincter
trace the flow of urine
nephrones, collecting ducts, papillary duct, minor calyx, major calyx, renal pelvis, ureter, bladder, urethra
what valve prevents backflow from the bladder to the ureters
there is no anatomical valves at the junction
how does urine move through the ureters to the bladder
peristaltic waves
how do the ureters enter the bladder
posteriorly at an oblique angle
bladder infection
kidney infection
what prevents the back flow of urine from the bladder into the ureters
physiological valves
normal urine pH
4.4 - 8.0
the average range for urine pH
5.5 - 6.5
this pH is observed in a pt w/ SEVERE metabolic acidosis
what would you use to evalute a pts acid-base balance
you draw an arterial blood sample on a pt and they have increased CO2
respiratory acidosis
you draw an arterial blood sample on a pt and they have decreased CO2
respiratory alkalosis
you draw an arterial blood sample on a pt and they have decreased HCO3-
metabolic acidosis
you draw an arterial blood sample on a pt and they have increased HCO3-
metabolic alkalosis
the body compensates for respiratory acidosis and alkalosis by
how the kidneys handle H+ and HCO3-
the body compensates for metabolic acidosis and alkalosis by
altering the respiratory rate
blows off excess CO2
retains CO2
how many nephrons does the body generate everyday
none - no new nephrons are formed and existing nephrons can't be repaired
how do the kidneys compensate for damaged nephrons
the remaining ones adapt by enlarging to handle the extra workload
at what point do clinical signs of dysfunction observed
>= 75% nephrons are damaged
what happens in the renal corpuscle
blood plasma is filtered
what happens in the renal tubules
filtered fluid passes
are there more cortical or juxtamedullary nephrons
cortical 80% > juxtamedullary 20%
these have loong loops of henle
juxtamedullary nephrons
these nephrons have corpuscles that are deep in the cortex
these have short loops of henle
cortical nephrons
these nephrons have corpuscles in upper & middle regions of the cortex
how much blood does an adult kidney filter per minute
what brings oxygenated blood to the kidneys
R & L renal arteries from the abdominal aorta