Ch 24 - Urinary system
What arteriole exits the glomerulus?
efferent
How (structurally) do the afferent and efferent arterioles differ? How does this affect filtration?
efferent are smaller, and slow down blood. This allows time for filtration and increases pressure.
What are the steps involved in urine production?
1. filtration 2. reabsorption 3. secretion
Which kind of nephron does NOT extend deep into the medulla?
Cortical nephrons
How do the descending and ascending limbs of the Loop of Henle differ?
Descending- permeable and simple squamous epithelium Ascending- impermeable to water
Purpose of the loop of Henle extending so far into the medulla
The Loop of Henle, a distal convoluted tubule, and a collecting duct. Multiple tubules feed into the collecting ducts.
What arteriole feeds into the glomerulus?
afferent
Blood vessel that contains granular cells involved in blood pressure regulation.
afferent arteriole
Which limb of the loop of Henle is impermeable to water?
ascending limb
85% of nephrons are described by this term that relates to their location in the kidney.
cortical
Are most nephrons cortical or juxtamedullary?
cortical
Contraction of this muscle forces urine from the bladder
detrusor
What contracts to squeeze urine from bladder?
detrusor muscle
2 functions of the kidneys
eliminate nitrogenous wastes and maintain water and salt balance
Is the material in the kidney tubules filtrate or blood?
filtrate
Knot of capillaries that is drained by the efferent arteriole.
glomerulus
What structures comprise the renal corpuscle?
glomerulus + bowman's capsule
The medial concave cleft in which vessels, ureters, and nerves enter/leave the kidney.
hilum
How many nephrons are found in a renal pyramid?
millions
Cup-shaped tubes that enclose the papillae of the pyramids
minor calyx
smallest functional unit of the kidney, site of filtration
nephron
capillary beds around the tubules, adapted to absorb materials not retained in filtrate
peritubular capillaries
What is the actual site of filtration in a nephron?
renal corpuscle
Where are nephrons found in a kidney? (2 locations)
renal cortex and renal medulla
The descriptive term for the location of the kidneys relative to the abdominal cavity.
retroperitoneal
A large filled space within the kidney containing the renal pelvis, vessels, nerves, and fat
sinus
What tissue type lines the mucosa of the urinary bladder?
transitional epithelium and lamina propria
What is micturition?
urination
Ladderlike looping blood vessels within the medulla.
vasa recta
what is formed by thickening of detrusor muscle at bladder and urethra junction, and is involuntary?
internal urethral sphincter
What two structures are connected by the ureter?
kidney and bladder
Region of the distal tubule that monitors concentration of the filtrate.
macula densa
What surrounds urethra with skeletal muscle sheet, inhibits urine and is voluntary?
external urethral sphincter
location of the kidneys
retroperitoneal position, behind mesenteries of coelomic cavity
What can cause kidney stones?
dehydration, blockage of urine flow, bacterial infection
What is being monitored at the juxtaglomerular complex?
blood pressure
What is accomplished by secretion of renin-aldosterone? (the renin-angiotensin-aldosterone complex)
blood pressure is raised
What is the most important job of the collecting ducts?
conservation of body fluids