Urinary System

filter blood

major function of urinary system

kidneys

process about 180 L of blood per day

1%

what percent of blood is eliminated through kidneys per day

Ureters

brings fluid from the kidneys to the urinary bladder

urinary bladder

storage tank for urine

male urethra

carries both reproductive fluid and urine

female urethra

only carries urine

no

does the urinary system have accessory organs?

Filtration

predominantly uses pressure to move things across a selective membrane

plasma

the kidneys filter.....

decreases

by increasing the amount of fluid filtered in the kidneys, the amount of fluid in circulation

decrease

increasing the amount of fluid in the urinary system will _______ blood volume

tonicity

ions create the gradient that help move the fluid

gluconeogenesis

predominantly occurs in the liver, occurs sometimes in kidney

renin

leads to production of aldosterone by the adrenal cortex

Erythropoietin

hormone responsible for production of red blood cells, aka helps to maintain blood oxygen levels

vitamin D

kidneys activate the inactive ______ from skin

vitamin D

linked to calcium absorption from digestive system for bone health and muscle contraction

vitamin D

leads to cardiac, skeletal and smooth muscle contraction from absorption of calcium

renal capsule

external covering of kidney

cortex

all cortical tissue, outer region of kidney

renal pelvis

flat part of the kidney prior to the ureter, region

renal sinus

structure/space that exists AT the renal pelvis

renal pyramiuds

within medulla and triangle shaped

collecting ducts

stripes in renal pyramids that run parallel to each other

renal columns

extensions of the cortex into medulla, between pyramids

major calyces

where minor calyces empty into

minor calyces

where collecting ducts end and renal pyramids empty into, collecting chambers

hilum

indentation of the kidney

renal sinus

where major calyces dump into prior to fluid going into ureter

Kidneys

said to be retroperitoneal (behind the peritoneal)

adipose capsule

surrounds the kidneys for insulation, cushioning, and protection

renal fascia

anchoring the kidney in place, holds the kidneys to abdominal wall

nephron

the FUNCTIONAL structure of the kidney

glomerulus

vasculature component of the nephron

4

the renal tubule of the nephron has how many parts

glomerulus

capitalized, fenestrated capillary bed of kidney

glomerulus

unique bc it is between two ARTERIOLES

glomerulus

blood pressure here is higher than any other capillary bed

renal tubule

fluid leaks into this from capillaries

glomerular capsule

fluid leaking out of capillaries gets trapped and contained here

proximal convoluted tubule

part of the tube closest to the glomerular capsule

loop of Henle

part of the tube that descends/ascends towards/from the medulla

descending limb

attached to proximal convoluted tubule

ascending limb

attached to distal convoluted tubule

distal convoluted tubule

connects to a collecting duct, can connect to more than one renal tubule

renal corpuscle

combination of glomerulus and bowman's capsule

cortical nephrons

majority of our nephrons are these, 85%

cortical nephrons

when most of the nephron is in the cortex of the kidney

juxtamedullary nephron

some nephrons in the body are these, 15%

juxtamedullary nephrons

when the loop of Henle goes deep into the medulla

concentrated

the deeper we go into the medulla, the more ________ we make our urine

cortical nephrons

If BP is high, we need to lower BP and one way is to get rid of extra fluid in blood so process MORE in

peritubular capillaries

true capillary bed of kidneys, exists between an arteriole and venule, surrounds renal tubule

vasa recta

same as peritubular capillaries but these are located on juxtamedullary nephron

juxtaglomerular apparatus

modification where the distal convoluted tubule runs against the afferent arteriole

juxtaglomerular apparatus

smooth muscle cells enlarge and gain ability to secrete renin

macula densa cells

modified cells in the walls of the distal convoluted tubule

macula densa cells

what cells function as chemoreceptors and look for osmotic concentrations of filtrate

collecting duct

filtrate becomes urine when it leaves the

JG cells

activation of macula densa cells can activate

JG cells

modified smooth muscle cells located in the afferent arteriole

JG cells

mechanoreceptors that sense pressure differences in afferent arteriole

JG cells

produce and secrete renin

water absorption

aldosterone leads to

juxtaglomerular apparatus

found in both cortical/juxtamedullary nephrons

fenestrated endothelium

allows everything to pass through the capillary bed EXCEPPT blood cells and proteins

podocytes

cells around the basement membranes

podocytes

reduce the area that filtration can occur, create filtration slits

pedicels

impermeable extensions of podocytes

basement membrane

wraps around capillaries to limit size of what can pass out

basement membrane

holds an electrical charge that keeps proteins in, otherwise nonselective

glomerular filtration

the filtering movement of plasma from the bloodstream into the kidney tubule

glomerular filtration

passive, nonselective process, only selectivity comes from basement membrane

goes up

if the blood pressure goes up, then glomerular filtration

tubular reabsorption

removal of materials from filtrate back into circulation (tubule --> bloodstream)

proximal convoluted tubule

tubular reabsorption begins immediately in the

tubular reabsorption

can be active or passive process depending on the concentration gradient

glucose and amino acids

humans reabsorb all _____ and _____ from the filtrate

water and ions

reabsorption of what two classes is greatly affected by hormones

proximal convoluted tubule

most reabsorption happens where

aldosterone and ADH

absorption in the loop of Henle and distal convolued tubule are regulated by

tubular secretion

moves material from the capillaries into the renal tubule (bloodstream --> tubule)

proximal convoluted tubule

where does tubular secretion mostly occur

glomerular hydrostatic pressure (BP!)

the major regulator affecting filtration

glomerular hydrostatic pressure (BP!)

pressure of blood inside the glomerulus capillaries responsible for movement of plasma out of BV to become filtrate

colloid osmotic pressure of intracapsular space

pressure that draws fluid out into Bowman's capsule due to presence of proteins

colloid osmotic pressure of intracapsular space

typically zero because proteins cant get past the filtration membrane

colloid osmotic pressure of glomerular blood

Pressure that draws fluid into the glomerulus from Bowman's capsule due to the presence of proteins in the vessel

less filtration

more proteins in blood means

capsular hydrostratic pressure

pressure inside capsule working in opposition to glomerular hydrostatic pressure

capsular hydrostatic pressure

Under normal circumstances, this pressure is lower than glomerular hydrostatic pressure (BP)

lowers

albumin is protein so what happens to filtration