A&P Ch. 20: Urinary System
glomerular capillary bed
Blood flows from the ______ into the efferent arteriole.
capillary beds within renal medulla
Describe the vasa recta.
Glomerular capillary hydrostatic pressure (HPg):
Favors filtration.
efferent arteriole
From the glomerular capillaries, blood flows into which blood vessel?
filtration
Glomerular ______ involves the movement of water and other small dissolved molecules and ions from the glomerular capillary plasma into the glomerular capsule.
glomerular filtrate
Glomerular capsule contains what kind of fluid?
plasma
Glomerulus contains what kind of fluid?
Equation to calculate net filtration pressure:
HPg minus OPg and HPg.
hemodialysis
If a person is in renal failure, or if the kidneys are not functioning optimally, a person can be placed on____________ , a process in which an artificial kidney cleanses the blood.
glomerulus; nephron
In glomerular filtration, substances move from the ______ into the ______.
peritubular capillaries
Name the capillaries that surround the renal tubules within the renal cortex.
juxtamedullary nephrons
Name the subset of nephrons that has nephron loops extending deep into the renal medulla and renal corpuscles located near the renal medulla.
Capsular hydrostatic pressure (HPc):
Opposes filtration.
Glomerular capillary osmotic pressure (OPg):
Opposes filtration.
glomerular capillaries
Pores, called fenestrae, are found in the walls of the ______ and are important in allowing glomerular filtration.
tubular fluid.
Renal tubule contains what kind of fluid?
Ascending limb of the nephron loop meets the afferent and efferent arterioles.
The juxtaglomerular apparatus is located where which structures meet?
renin
The kidneys help to regulate blood pressure by secreting an enzyme called:
red blood cell production
The kidneys release a hormone called erythropoietin which regulates ______.
cortical
The nephrons classified as ______ nephrons are located close to the kidney surface and have relatively short nephron loops.
juxtaglomerular apparatus
What is located where the ascending limb of the nephron loop passes between the efferent and afferent arterioles?
favors filtration
What is the effect of hydrostatic pressure of blood on filtration?
vasa recta
What type of capillary bed forms a relatively straight capillary loop in the renal medulla?
out of the glomerular capillaries
When considering all of the pressures occurring within the renal corpuscle, does the NET PRESSURE move fluid into or out of the glomerular capillaries?
renal corpuscle and renal tubule.
Which are the two major components of a nephron?
afferent arteriole
Which arteriole brings blood from the cortical radiate arteries into the nephron?
peritubular.
With the cortical nephrons, blood passes from the efferent arterioles directly into the _____________capillaries.
The electrochemical gradient generated as the cation sodium (Na+) is actively reabsorbed from the proximal tubule leads to reabsorption of ______ such as Cl- by diffusion.
anions.
The electrochemical gradient generated as sodium is actively reabsorbed from the proximal tubule also leads to the reabsorption of_____________ by diffusion.
chloride.
JG cells and macula densa:
constitute the juxtaglomerular apparatus.
What is the function of renin?
convert angiotensinogen to angiotensin I.
What is the amount of filtrate formed per minute by the two kidneys called?
glomerular filtration rate.
The first step in urine formation involves which process?
glomerular filtration.
The process by which the glomerular capillaries filter plasma is called:
glomerular filtration.
Juxtaglomerular apparatus:
helps control renin secretions.
HP:
hydrostatic pressure
If ADH levels are high, ______ water will be reabsorbed and ______ water will be excreted in the urine.
more; less
Water is reabsorbed from the proximal tubule by the process of ______ as it follows sodium reabsorption. The result is a(n) ______ in tubular fluid volume.
osmosis; decrease.
Active reabsorption of sodium from tubular fluids results in a passive secretion of which of the following?
potassium ions.
Which substance is reabsorbed in the proximal tubule via endocytosis?
protein.
Most of tubular reabsorption occurs in which segment of the renal tubule?
proximal tubule.
Movement of materials from the renal tubule into the peritubular capillaries is called tubular:
reabsorption.
Detrusor:
the smooth muscle of the urinary bladder that is mainly responsible for emptying the bladder during urination.
Net Filtration Pressure (NFP)
total pressure that promotes filtration.
The proximal tubule is the primary location for which process?
tubular reabsorption.
Indicate which three of these situations would result in an increase in GFR:
vasoconstriction of efferent arteriole; increased arterial blood pressure; decreased glomerular osmotic pressure.
Angiotensin II causes ______ of arterioles in the kidneys, thus ______ GFR overall.
vasoconstriction; decreasing.