Chapter 10: Renal/Excretory System Flashcards
What structures make up the renal/excretory system?
- Pair of kidneys
-pair of ureters
-urinary bladder
-urethra.
What is the function of the ureters?
Convey urine from kidneys to urinary bladder.
What is the function of the urinary bladder?
Stores urine until voided, made of smooth muscles.
What is the function of the urethra?
Conveys urine from bladder to outside (shorter in men).
What is the anatomical location of the kidneys?
-Bean-shaped
-bilateral
-located in the lumbar region (12th thoracic to 3rd lumbar vertebrae).
Why is the right kidney lower than the left kidney? n size
-right kidney is 2 cm lower than the left due to the position of the liver
-4.5 inches long, 2.5 inches wide, and 1 inch thick.
What are the layers surrounding the kidneys?
Fibrous capsule
Perirenal fat
Renal fascia
Pararenal fat
What is the renal papilla’s role in the kidney?
Collecting ducts open into minor calyces, which drain into major calyces.
What is the structure of the kidney?
Major calyx: Minor calyces combine to form the major calyx.
Renal pelvis: Collects urine from the major calyx.
Renal column: Space between renal pyramids, containing blood vessels and nerves.
Cortex: Outer part, contains proximal convoluted tubule (PCT), glomerulus, distal convoluted tubule (DCT).
Medulla: Inner part, contains Loop of Henle, collecting duct, and collecting tubules.
What is the orientation of the nephron within the kidney?
Cortex: Bowman’s capsule, PCT, DCT.
Medulla: Loop of Henle, collecting ducts, collecting tubules.
What is the function of the nephron in the kidney?
The nephron is the functional unit of the kidney, involved in filtration, reabsorption, and secretion to form urine.
What is the blood supply to the kidneys?
The kidneys receive 20-25% of cardiac output (~1200-1250 mL/min).
Describe the blood flow pathway to the kidneys.
Left ventricle → Aorta → Renal artery → Segmental artery → Interlobar artery → Arcuate artery → Cortical radiate artery → Afferent arteriole → Glomerulus.
What happens at the glomerulus?
Filtration occurs, blood is filtered into glomerular filtrate.
Describe the return flow of blood from the kidneys
Efferent arteriole → Cortical radiate vein → Arcuate vein → Interlobar vein → Renal vein → Inferior vena cava → Right atrium.
What is the structure and function of Bowman’s capsule?
- cup-shaped
-contains the glomerulus
-It is part of the renal corpuscle where blood filtration takes place.
What is the difference between the parietal and visceral layers of Bowman’s capsule?
Parietal layer: Flat, squamous cells.
Visceral layer: Specialized cells (podocytes) that wrap around the capillaries with foot processes.
How does filtration occur in Bowman’s capsule?
Blood passes through fenestrated capillaries → Podocyte foot processes → Filtrate goes through filtration slits into Bowman’s space.
What is the purpose of the podocytes in Bowman’s capsule?
Podocytes have foot processes that wrap around the capillaries, aiding in filtration by creating filtration slits.
How many nephrons are in each kidney?
Each kidney has approximately 1 million nephrons.
What are the main components of the renal corpuscle?
Glomerulus + Bowman’s capsule.
What are the components of the Loop of Henle and their functions?
Descending limb: Permeable to water and sodium, thin segment with flat cells.
Ascending limb: Permeable only to sodium (not water), thick segment with cuboidal cells.
What happens in the distal convoluted tubule (DCT) and collecting tubule?
They combine to form the collecting duct, which opens at the minor calyx and carries urine out.
How much reabsorption occurs in the DCT, and what is reabsorbed?
80% of reabsorption occurs in the DCT, including sodium and water.