renal system Flashcards
What are the parts of the renal system
Kidneys (produce/ excrete urine)
Urinary track (elimnate urine)
- ureters (paired tube)
- urinary bladder (muscular sac)
- urethra (exit tube)
What is urination. micturition and how does it take place
Process of eliminating urine
Contraction of muscular urinary bladder forces urine thorugh urethra and out of body
What is the function of the renal system
Excretion
- removal of organic wastes from body fluids
Elimination
-discharge of waste products
Homeostatic regulation
- regulation of blood plasma volume and solute concentration
Regulates blood volume and b.p
- adjusting volume of water lost in urine and releasing etythropoeitin and renin
Regulates plasma ion concentrations
- Sodium, potassium and chloride ions
- calcium ion levels
Stabilize blood pH
- controlling loss of hydrogen ions and bicarbonate ions in urine
Conserves valuable nutrients
- preventing excretion while excretion organic waste products
Location of kidney
Located on either side of the vertebral column
Left kidney superior to the right
what is the position of the kidneys maintained by
Overlying peritoneum, contact with adjacent visceral organs and supporting connective tissues
What are the differnet parts of the kidney (not v impt)
Hilum, fibrous capsule, renal cortex and renal medulla, major calyx and renal pelvis
What is the blood supply of the kidney
Adrenal artery and renal artery
Renal vein
What is a nephron and where is it located
It is the basic functional unti of the kidney where urine production begins and is located in the cortex of each renal lobe
What structures make up the renal corpuscle
Bowman’s capsule and the capillary network, glomerulus
Is where the renal tubule begins
What are the functions of the nephron
Renal corpuscle
- site of filtration
Renal tubule
- reabsorbs urseful organic nutrients that enter filtrate
- reabsorb more than 90% of water in filtrate
- secrete waste products that failed to enter renal corupscle through filtration at glomerulus
State what takes place at the proximal convoluted tubule (PCT)
Reabsorption of water, ions and all organic nutrients
State what takes place at the distal convolute tubule (DCT)
Secretion of acids, drug and ammonia
Vairable reabsorption of water, sodium ions
What is the function of collecting ducts
Receive fluid from many nephrons and carries fluid to papillary duct that drains into a minor calyx
Juxtaglomerular complex (IDK if i needa know this)
An endocrine structure that secretes erythropoietin and renin
What is the puprose of urine prodution
Maintain homeostasis by regulating volume and composition of blood and excretion of metabolic waste products (urea, creatinine and uric acid)
What happens to organic waste products
Dissolved in bloodstream, elimintaed while dissolved in urine and removal is accompanies by water loss
What is the basic process of urine formation
Filtration at glomerulus
- Blood pressure force water into renal corpuscle bringing along solute molecules
Reabsorption at the PCT
- reabsorption of fluid and solute molecules into the peritubular fluid to return to blood circulation
Secretion at the DCT
- transport of residue solute molecules that are not removed by filtration into tubular fluid and then into the urine
What hormones play a role in reabsorbtion and secretion at the renal tubule
Anti-diuretic hormone (ADH): reansorption of water into blood resulting in more concentrated urine
Aldosterone: Reabsorption of sodium ions into blood to prevent loss in urine
What are the solutes normally found in the urine
Sodium and potatassium ion
Urea, uric acid and creatinine
Ammonia
Bicarbonate ions
What is glomerular filtration rate (GFR) and the average amount produced per minute
Amount of filtrate kidneys produce each minute
Average 125 mL/min
What affects the GFR
Autoregulation
Autonomic regulation
Hormonal regulation
Blood pressure impact on the GFR
Reduced blood flow decreases GFR, dilation of afferent arteriole n glomerular capilaries, constriction of efferent arterioles
Rise in renal blood pressure
Constricts afferent arteriolesm decreases glomerular blood flow and thickning of glomerulus and arterioles resulting from long term high BP
What is the function of the ureters
Transport urine from kidneys to urinary bladder
How many liters of urine are produced in a day
1 to 1.8 liters
what is the function of the urethra
Urine excretion, from urinary bladder to exterior of body
In females it only carries urine
In males it caries urine and sperm
what is micturition
emptying of the urinary bladder
What are the age related changes to the renal system
Decline in number of functional nephrons
Reduction in GFR
Reduced sensitivy to ADH and aldosterone
Problems with micturition reflex
- sphincter muscles lose tone leading to incontinence
- control of micturition can be lost due to a stokem, Alzheimer’s diseasem, and other CNS problems
- urinary retention may develop in males if enlarged prostate glad compresses the urethra and restricts urine flow
What will not be found in the urine
RBC
Glucose
Protein
