Urinary System Pt. 2 Flashcards
How do the kidneys receive blood?
Through their renal artery
What do renal artery segments divide into?
Segmental arteries
Where do interlobar arteries radiate towards within the kidney?
Towards the renal columns between the pyramids
What do arcuate arteries supply, and where do they arch?
Arcuate arteries supply the cortex and medulla boundary, arching along it
What is the role of cortical radiate arteries?
They deliver blood to capillaries supplying individual nephrons
What is the path of blood after it goes through the capillaries in the nephron?
It goes into the cortical radiate veins, then into the arcuate veins, and finally into the interlobar veins, which connect to the renal vein
How are the kidneys innervated by renal nerves?
Renal nerves follow the renal arteries to reach individual nephrons
How does sympathetic innervation influence urine formation?
It adjusts the rates of urine formation by changing blood flow at the nephron and influences urine composition by stimulating the release of renin
What is the role of nephrons in the kidneys?
Nephrons are the smallest structures that carry out all of the system’s functions
What are the two main components of a nephron?
Renal corpuscle and renal tubule
Describe the renal corpuscle.
It is a spherical structure containing a capillary network that filters blood
What is the renal tubule?
A long, tubular passageway that begins at the renal corpuscle and empties into the collecting system
How big is the glomerular capsule in the renal corpuscle?
It has a diameter of 150-250 micrometers
What structures make up the filtration membrane in the renal corpuscle?
Fenestrated endothelium, the basement membrane, and the foot processes of podocytes
What happens during filtration in the renal corpuscle?
Blood pressure forces water and small dissolved solutes out of the glomerular capillaries through the filtration membrane and into the capsular space
What is the filtrate in the context of the renal corpuscle?
The fluid and dissolved solutes forced out of the blood during filtration
How does the renal tubule begin after the renal corpuscle?
With the proximal convoluted tubule
How does the nephron loop follow the proximal convoluted tubule?
It consists of a descending limb and an ascending limb
What is the purpose of the distal convoluted tubule?
To further process the filtrate
What is the juxtaglomerular apparatus in the nephron?
A region where the distal convoluted tubule contacts the afferent and efferent arterioles
What is filtration in the context of the nephron?
The process of forcing blood through the filtration membrane in the renal corpuscle
Describe the components of the filtration membrane in the renal corpuscle.
It consists of fenestrated endothelium, the basement membrane, and the foot processes of podocytes
What type of substances can pass through the filtration membrane into the capsular space?
Water and small dissolved solutes
What is the filtrate in the context of blood filtration?
The fluid and dissolved solutes that are forced out of the blood during filtration
What does the filtration process do to blood pressure in the glomerular capillaries?
It increases the blood pressure in the glomerular capillaries
What is the primary force for glomerular filtration?
Glomerular hydrostatic pressure
What is the colloid osmotic pressure of the glomerular capillaries?
It opposes filtration
How do capsular hydrostatic pressure and colloid osmotic pressure affect filtration?
They decrease filtration by opposing the glomerular hydrostatic pressure
What is the net filtration pressure in the glomerular capillaries?
The difference between glomerular hydrostatic pressure and the sum of capsular hydrostatic pressure and colloid osmotic pressure
What is the approximate GFR (glomerular filtration rate) in a typical person?
125 ml/min
