Kidneys and Urinary Systems Flashcards
Shape and colour of kidneys
They are bilateral bean-shaped organs, reddish-brown in colour
Anatomical position of the kidneys
At the posterior end of the abdomen from T12 to L3
The left kidney is often situated slightly lower due to the presence of the liver. True or false?
False
Dimension of the kidney
12cm x 6cm x 4cm (L, W,T)
Kidneys function
- Filter and excrete waste products from the blood.
- Water and electrolyte balance in the body.
Layers of fat that enclose the kidneys
Pararenal fat/Renal capsule
Perirenal fat
Renal fascia (also known as Gerota’s fascia or perirenal fascia)
Surfaces of the kidney
Anterior
Posterior
Which surface of the kidney has peritoneum?
Anterior
On which border of the kidney do we have the hilum?
Medial
Poles of the kidney
Superior
Inferior
Which pole is thicker, broader and more rounded?
Superior
Which pole is closer to the median line?
Superior
The renal parenchyma can be divided into…
…two main areas – the outer cortex and inner medulla
Compartments of the kidney
Cortex
Medulla
Renal pelvis
The cortex and its function
It is the outer part between the capsule and medulla.
Function - Ultra filtration
Contents of renal cortex
Bowman’s corpuscles
Renal tubules except for loop of Henle
Which part of the renal tubules is not in the cortex?
Loop of Henle
The medulla is divided into pyramids called…
…renal pyramids
The apex of a renal pyramid is called…
…a renal papilla.
Function of the minor calyx
Collects urine from the pyramids.
The spaces between the renal pyramids are called…
…the renal column of Bertin
The major calyx is…
…a combination of 2 to 3 minor calyces that unite near the hilum to form the pelvis
What is the shape of the renal pelvis?
Funnel
Function of the renal hilum
It acts as a gateway to the kidney – normally the renal vessels and ureter enter/exit the kidney via this structure.
The suprarenal glands are positioned…
On the superomedial part of the kidneys
Hormones secreted by the adrenal glands
Aldosterone
Adrenaline
Norepinephrine
Aldosterone is for…
…regulation of salt and water. This is its only kidney-related function.
The ureter runs from…
…the renal pelvis to the bladder
The abdominal part of the ureter runs from…
Renal pelvis to pelvic brim
Clinical conditions associated with the kidney
Diabetes Milletus - Inability to respond to or produce insulin
Diabetes insipidus - Inability of kidneys to concentrate urine
Renal failure
Urinary Tract Infection (UTI)
Important hormones produced by the kidneys
Erythropoietin, calcitriol, and renin.
The cortex of the kidney has a granular appearance. Why?
Due to many capillaries
Mechanisms of urine production
3 stages:
- Filtration
- Reabsorption
- Secretion
Blood supply chain of the kidneys
Renal arteries Segmental arteries Lobar Interlobar Arcuate Interlobular Afferent arteriole Glomerulus (capillaries) Efferent arterioles (at nephrons) Peritubular capillaries & vasa recta Interlobar Arcuate Interlobular Renal vein
Rinu Said I Am In A Great Efferent Please I Am In Renal vein
Blood filtrate enters the nephron but no blood cells or large proteins enter as part of filtrate. True or false?
True
Renal corpuscle is the…
…site of filtration
The network of capillaries at the renal corpuscle site is
glomerulus
The glomerulus has afferent & efferent capillaries and venuoles. True or false?
False. There are no venuoules
The glomerulus is surrounded by
Glomerular capsule (Bowman’s capsule)
The cells of glomerular capsule are called…
Podocytes
What makes the renal corpuscle high permeable?
The site has fenestrations on capillaries & filtration slits within podocytes, making it highly permeable.
Connecting to the renal corpuscle are tubules responsible for…
…reabsorption and secretion.
The first tubule after the glomerulus is…
Proximal Convoluted Tubule (cortical nephron)
The PCT is surrounded by…
… peritubular capillaries.
The PCT goes into a long loop called..
Loop of Henle.
The ascending limb of the PCT connects to…
DCT which connects to collecting tubules.
Blood vessels in Loop of Henle are called? What is their function?
Vasa recta. They are involved in concentrating urine.
The collecting tubules collect…
…urine from several nephrons & run into medulla where they merge with other collecting tubules to form papillary ducts that empty into minor calyces.
Effect of dehydration on collecting tubules
They become more permeable & allow water to be reabsorbed, reducing urine volume & increasing its concentration.
Which microscopic part of the neuron is responsible for ABP regulation?
Juxtaglomerular apparatus
The juxtaglomerular apparatus released a hormone called
…rennin as a response to falling BP.
Renin causes
…an increase in blood solute concentration which leads to an increase blood volume and thus increased BP
Where in the kidneys is erythropoietin produced?
Interstitial connective tissue
The interstitial connective tissue are…
…layers of connective tissue that surround uriniferous tubules & contain cells that release hormones to influence BP & RBC production
The ureters carry urine from the kidneys to the…
Urinary bladder
Length of the ureters about 10 inches long,
10
The ureters runs from
…the renal pelvis & reaches the bladder medially on its posterior wall.
The ureter enters the bladder at an…
…oblique angle to prevent back flow. Forms 2 points of trigone.
3 layers of the ureter
Mucosa
Muscularis
Adventitia
Urine reaches bladder through…
…peristalsis. Muscle contractions seem to be guided by a reflex response.
The muscular sac that stores urine is the…
Urinary bladder
When the bladder is empty…
It collapses but it can I expand enough to enter into abdominal cavity
Location of the urinary bladder in males
Lies anterior to rectum
Location of the urinary bladder in females
Lies anterior to uterus & vagina
Layers of the urinary bladder
Mucosa
Muscularis
Adventitia
The thin tube that drains urine out of the body from bladder is the…
Urethra
The urethra is longer in females than in males. True or false?
False
In females, the opening of the urethra lies…
…posterior to clitoris & anterior to anus
In males, the urethra opens…
…at tip of penis & carries both urine & semen
Control of urine by the urethra
An involuntary sphincter muscle keeps urethra closed when there is no urine while a voluntary sphincter constricts urine flow until appropriate time to void.
Urination or voiding occurs when…
…pressure in bladder is increased either by bladder muscle and/or abdominal muscle contraction
Micturition is controlled by…
…the brain.
How does the PNS control micturition?
Parasympathetic neurons stimulate contraction of muscle to induce voiding
How does the ANS control micturition?
The sympathetic branch stimulates sphincter to prevent micturition.
Disorders of the urinary system
Urinary tract infections
Renal Calculi or kidney stones
Causes of UTI in women
It results from intercourse because it brings bacteria into urethra & spermacides kill natural living bacteria in vagina
Causes of UTI in men
It can arise from long-term catheterization.
Symptoms of UTI
Frequent micturition accompanied by burning sensation & fever
Kidney stones form when…
… calcium, magnesium, or uric acid salt precipitate & accumulate and obstruct a ureter.
Dehydration can cause kidney stones. True or false?
True
Cancers of the urinary system
Bladder cancer
Kidney cancer
Bladder cancer is 5 times more common in men than in women. True or false?
True
Bladder cancer arises from…
… transitional epithelial cells of mucosa.
Kidney cancer arises from…
epithelial cells of uriniferous tubules or renal pelvis.
Risk factors and symptoms for bladder cancer
Arise from exposure to tar in tobacco smoke, chemicals, & artificial sweetners. Blood in urine is a sign of bladder cancer.
Who is more likely to have kidney cancer?
Men
Risk factors for kidney cancer
- obesity
- high blood pressure
- high protein diet
