Anatomy Of Urinary System Flashcards
What are the main functions of the kidney and urinary tract?
Excretion of waste products and drugs from blood
Regulates BP and Body fluid volume
Acid-base balance
Endocrine (Renin production for BP and Na+ balance), Erythropoietin (erythrocyte prod), prostaglandins (regulate renal function)
Metabolism - Vit D metabolised to active form
Catabolism of insulin, parathyroid hormone and calcitonin
What endocrine hormones does the kidney produce?
Renin
Erythropoietin
Prostaglandins
In terms of the peritoneum, where are the kidneys located?
Retroperitoneal organs
On posterior abdominal wall along side each side of the vertebral column
With reference to vertebral levels where are the kidneys located?
Between T12 and L3
What ribs partially protect the kidneys?
Ribs 11 and 12
How does the position of the left kidney compare to the right kidney?
Why?
The right kidney sits lower than the left kidney due to the liver being superior to it
What is the name of the inner curvature of each kidney where the blood vessels attach?
Hilum
What vertebral level is the Hilum?
L1
Normally the kidney is about 11cm and 6cm wide, how small does the kidney have to be to indicate CKD?
Less than 8cm indicates chronic kidney disease
What are the kidneys held in place by?
Fat
What are the layers of fat/layers holding the kidney in place from superficial to deep?
Paranephric/pararenal fat
Renal fascia
Perinephric/perirenal fat
Renal capsule
Then kidney
How do the ureters travel from the kidney with respect to the vertebra?
In line with the transverse processes of the Lumbar vertebra
What major blood vessels supply the kidneys?
What do they branch into?
Abdominal aorta branches into the right and left renal arteries which plug into the hilum of each kidney
Inferior vena cava branch’s to right and left renal vein
Why are the left and right renal arteries a different length to each other?
Left renal artery is longer since it needs to get past the inferior vena cava
The IVC is more on the RHS and the Abdominal aorta is more on the Left side
What are the 2 main parts to the kidney?
Renal Cortex
Renal medulla
What parts of the nephron are located in the renal cortex?
Glomerulus
Bowmanns capsule
Proximal Convoluted Tubule (PCT)
Distal Convoluted Tubule (DCT)
What parts of the nephron are located in the renal medulla?
Loop of Henle
Collecting ducts
Where and what are the dark triangles in the cross section of kidney?
They are renal pyramids located in the renal medulla
What is a renal lobe?
A renal pyramid with its overlying cortex
What is the name of the structure that the collecting ducts drain into leading from the renal pyramids?
Minor calyces is where the collecting ducts drain to, these then join up forming major calyces
What do the major calyces join to form?
Ureter
What are the 2 types of nephron?
Cortical nephron
Juxtamedullary nephron
What is the key defining difference between a cortical nephron and a juxtamedullary nephron?
Cortical = short Loop of Henle
Juxtamedullary = Long loop of Henle
What type of Arteriole brings blood to the glomerulus and what type of arteriole takes blood away from the glomerulus?
Afferent = blood Arrives at glomerulus
Efferent = blood leaves glomerulus
What type of cell is important in the glomerulus forming a sieve to filter blood?
What feature allows for filtration to occur?
Podocyte
Foot processes
What are the 2 different capillary types that the Efferent arteriole goes onto form?
Peritubular capillaries
Vesa recta
Where are the peritubular capillaries located?
Around the PCT and DCT
Where are the Vesa recta located?
Around the Loop of Henle (LOH)
What region of the nephron does the hormone ADH act on?
What general affect does it have?
Collecting duct
Causes more water to be reabsorbed so the urine becomes more concentrated
In 2 adjacent nephrons how is the glomerulus and bowman’s capsule of the one nephron positioned compared to the other nephron?
The GLomerulus and bowman’s capsule is located right next to the other nephrons DCT
Why is the renal corpuscle located next to another nephrons DCT?
What cells do this job?
The Macula densa cells can sense the composition of the fluid flowing through the nephron
What cells secrete Renin?
Granular cells
What is an easily identifiable artery that branches from the abdominal aorta and where is it?
Superior Mesenteric Artery
It sits on top of the renal veins
What is the significance of the inferior mesenteric artery in embryological development?
It stops the ascent of the kidneys in embryological development
What is the blood supply within the kidney?
Renal artery -> branches to Segmental arteries -> branch into interlobular arteries which go between lobes -> branch to arcuate artery which runs in an arch -> branches to interlobular artery -> afferent arteriole -> Glomerulus -> efferent arteriole -> either peritubular capillaries or vesa recta
What is the blood supply leaving the kidney?
Interlobular vein -> arcuate vein -> interlobular vein -> renal vein
What makes up the ureters?
Smooth muscle fibres
With respect to the peritoneum, what type of structure are the ureters?
Retroperitoneal
What is the pelviurieteric junction?
Where the pelvis and ureter come together
Where is the most common area of uteric injury?
Pelvic brim
What bony landmarks can be used to find the ureters?
L1 can find itt from the hilum
Crosses sacrum and sacroiliac joint
Ureter kinks at Ischial spine
What is the name of the muscle forming the bladder?
What type of muscle is this?
Deter us or muscle
Smooth muscle
What are the folds / ridges called in the detrusor muscle?
Rugae
What is the function of Rugae in the detrusor muscle of the bladder?
Allows bladder to expand as it fills with urine
What is the area called with no Rugae in the detrusor muscle called in the bladder?
Trigone
What 3 points make up the Trigone in the bladder?
2 uteric openings
Internal urethral orifice
What forms the smooth trigone in the bladder?
Mesonephric duct
What is the importance of the oblique angle in the bladder?
As ureter enters bladder it forms a flap, the pressure of water in the bladder keeps the flap closed preventing urine moving up into the ureters and back to the kidney
What type of epithelial cells line the bladder?
Transitional epithelium/Urothelium
When the bladders empty it rests on the pubic symphysis, where in men and where in women?
Women = in front of vagina, uterus and rectum
Men = in front of rectum
How much urine can the average bladder hold?
750ml
How does the length of urethra compare in men and women?
What is the significance of this?
Women it’s shorter so more prone to UTIs
Why do people with enlarged prostate glands have trouble urinating?
The urethra passes directly through the centre of the prostate gland so it can get compressed
What are the 2 types of sphincter in the urethra?
Internal Urethral Sphincter
External urethra sphincter
Which of the 2 urethral sphincters is under voluntary control?
External urethral sphincter under voluntary control
Internal urethral sphincter involuntary
When does the internal urethral sphincter open?
When the pressure reaches a certain amount in the bladder
Where is the external urethral sphincter located in both men and women?
Urogenital diaphragm
What is the first part of the male urethra called?
Prostatic urethra
What follows the prostatic urethra in the area of the External urethral sphincter?
Membranous urethra (called this as it passes through the diaphragm)
What is the part of the urethra called as it passes through the penis following the membranous urethra?
Penile/spongy urethra
