PBL 9 Flashcards
How big are the kidneys?
Approximately 11cm long
Where are the kidneys located?
On the posterior abdominal wall, either side of the vertebral column, approximately at level T12 to L3.
Why does the right kidney lie slightly lower than the left?
The large right lobe of the liver restricts it superiorly.
What is the shape of the kidney?
The lateral margin of each kidney is smoothly convex, while the medial margin is concave, and further indented in the middle at the hilum.
What is the function of the hilum in the kidneys?
The renal vessels and the renal pelvis enter and exit the kidney.
What are the three layers of supportive tissue that cover each kidney?
The renal capsule, the adipose capsule and the renal fascia
What is the renal capsule?
A thin fibrous sac made of dense, irregular connective tissue that adheres closely to the kidney.
What is the function of the renal capsule?
It maintains the shape of the kidney and protects it from trauma and infection
What is the adipose capsule?
a layer of fat that surrounds the renal capsule of the kidney
What is the function of the adipose capsule?
It protects and supports the kidney
What is the renal fascia?
A layer of tissue that passes in front of and behind both kidneys. It is made of dense irregular connective tissue and attaches to the renal capsule by strings of fibres.
What is the function of the renal fascia?
It provides anchorage of the kidneys to surrounding structures
What is the renal cortex?
the outer 1 cm of the kidney that contains the arcuate and interlobular arteries and veins and cortical nephrons (except for parts of the loop of henle and the collecting tubules which descend into the medulla.
What function occurs in the renal cortex?
Ultra filtration
What are the renal columns?
Extensions of the cortex that project in between the pyramids of the medulla and help anchor the cortex.
What is the renal medulla?
The inner section of the kidney that lies deep to the cortex and contains the renal pyramid. The medulla appears striated as it contains the striated as it contains the tubular systems of the juxtamedullary nephrons, as parts of the loop of Henle and collecting tubules of the cortical nephrons
What are the renal calyces?
Renal pyramids drain into minor and major calyces which in turn empty into the renal pelvis, and ultimately, the ureter
What are the renal pyramids?
Cone shaped structures that terminate medially by protruding into the minor calyces. They appear striated because they are packed with bundles of nephron loops and collecting tubules, plus associated capillaries.
What is the renal papilla?
Where the tips of the pyramids protrude into the minor calyces. Here all the urine from the collecting tubules into the minor calyces.
What are minor calyces?
Cup like projections that surround the papilla of each pyramid. Several minor calyces converge to for a major calyce.
What are major calyces?
There are two or three in each kidney. They join to form the renal pelvis
what is the renal pelvis?
A single funnel shaped structure located centrally at the hilum of the kidney. it drains into the ureter
Outline the flow of urine?
Renal pyramid—papilla—minor calyces—major calyces—renal pelvis—ureter
What supplies blood to the kidneys?
Renal arteries arising directly from the abdominal aorta .
How much of the blood pumped out of the heart do the kidneys receive?
Since the kidneys are so important in the regulation of blood composition they receive roughly 20%
Where does the renal artery go?
It passes laterally from the abdominal aorta to reach the hilum of the kidney before branching into segmental arteries
Where do the segmental arteries go?
They branch from the renal artery and split into interlobar arteries
Where do the interlobar arteries go?
Pass through the renal columns
Where do the arcuate arteries go?
Leave the interlobar arteries at right angles to branch over the outer surface of the pyramid, forming an arterial anastamosis
How many renal pyramids are there?
8-10
What is an arterial anastomosis?
A connection between two arteries
Where do the interlobular arteries go?
They branch from the arcuate arteries to supply the cortex
What are the interlobular arteries also known as?
cortical radiate arteries
Outline the flow of blood into the kidneys?
Renal artery—segmental arteries—interlobar arteries—arcuate arteries—interlobular arteries—afferent arterioles
What are the afferent arterioles?
Each nephron receives one arteriole,which then divides again to form a plexus of capillaries of capillaries around the nephron
Outline how blood leaves the kidneys?
Efferent arterioles—arcuate veins—interlobar veins—renal vein
How big is the prostate?
Roughly 3cm in diameter
Where is the prostate situated?
Underneath the bladder, and it surrounds the beginning of the urethra