Renal System Flashcards
What does the renal system consists of?
Two kidneys
Two ureters
Bladder
Urethra
What is the function of the renal system?
Bodies plumber
Removes waste that is found in urine : urea, uric acid, ions and certain drugs
Balance fluids and electrolytes
What cavity is the kidneys located?
Abdominal cavity
Where is the kidneys located roughly on the abdo split into 9?
Right and left lumbar region going partly into hypochondriac region
Where is the kidneys located when abdo split into 4?
Right and left upper quadrant
Where is the kidneys located compared to other organs?
Inferior to diaphragm
Inferior and posterior to liver
Posterior to intestine
What shape is the kidneys?
Bean shaped
What is the average size of an adult kidney?
5-7cm x 10-13cm
What is the kidney?
A vascular organ
What is the kidney protected by?
Fibrous capsule
Layer of fat
Contend of the abdomen
Muscles
What do each kidney have?
Supply of blood
Adrenal gland
What enzyme affects the adrenal gland?
Renin
What does the enzyme renin do?
Regulates the body’s balance of fluids and electrolytes, which overall regulates blood pressure and sodium and water retention
What are the key functions of the kidneys?
Formation of urine, maintaining water, electrolyte and acid-base balance
Excretion of waste products
Production and secretion of renin, an important enzyme in the control of blood pressure
Production and secretion of erythropoietin, the hormone that stimulates the formation of red blood cells
What is the name of the capsule that surrounds the kidney?
Renal capsule
What is the cortex of the kidney?
A reddish brown layer of tissue immediately below the capsule and outside the renal pyramids
What are renal pyramids in the kidney?
Pale, conical shaped striating in the medulla inner mist layer
What are calyces?
Chambers where the urine passes through
Where do kidneys receive waste filled blood from?
Abdominal aorta
How does the filtered blood return to circulation in the kidneys?
Renal vein
How many nephrons do kidneys have?
1-2 million and even more collecting ducts
What are the two main functions of the nephron?
Filter fluids, wastes and electrolytes, acids
Selectively reabsorb secreting ions allowing precise control of fluid and electrolyte balance
What is the Bowmans capulse?
Surrounds the glomerulus
What does the nephron consist of?
Glomerulus Bowmans capsule Proximal convoluted tubule Loop of Henle Distal convoluted tubule
What prevents if cardiac output do kidneys receive?
20%
What is the difference between the afferent and efferent arteriole?
Afferent has a larger diameter
Why does the afferent arteriole have a larger diameter?
Drives filtration across the Bowmans capsule
What aids filtration?
Fenestrations
Basement membrane
Podocytes (pedicles)
Why is the Bowmans capsule more permeable than most capillaries?
It has flattened epithelium
What nerves supplies the renal blood vessels?
Sympathetic and parasympathetic
Where does filtration take place?
Takes place at the glomerulus
What do fenestrations prevent?
Plasma proteins and larger molecules passing through
What does blood or larger molecules like glucose in the urine suggest?
Damage in the fenestrations of the kidneys
What is autoregulation?
Maintain blood pressure between 80-200mmHg independently of autonomic control
What happens when blood pressure falls below 80mmHg in terms of the kidneys?
Selective reabsorption
Where does selective reabsorption mainly take place?
Proximal convoluted tubule
What are the walls of the proximal convoluted tubule lined with?
Microvilli
What are the three main substances reabsorbed in the PCT?
Water
Electrolytes
Glucose
What percentage of filtrate reaches the medullary loop (loop of Henle) ?
60-70%
What electrolytes are reabsorbed in the medullary loop (loop of Henle) ?
Sodium and chloride
What percentage of the original filter are reaches the DCT?
15-20%
Why don’t all substances get filtered at the glomerulus?
Short filtration time
Happens with aspirin and penicillin
Where is the substances removed from at the glomerulus?
Peritubular capillaries
What happens in DCT?
Balancing of concentrates
What is water excited through? (4)
Urine
Sweat
Expired air
Faeces
What volume of urine needs to be produced per day to expel waste products?
500ml
Where does the urine leave the kidney?
Ureter
What is ureters?
Tubes that connect each kidney to the bladder
Which kidney and ureter is higher than the other?
Left
What is the length of the left ureter?
30cm
What is the diameter of the ureter?
3mm
What are the three layers of the ureters?
Outer fibrous coat:
Holds ureter in place
Muscularis:
Contains smooth muscle
Mucosa:
Inner layer
What is the functions of the ureter? (3)
Acts as conduits that carry urine from kidneys to bladder
Peristaltic waves occurring 1-5 times a minute channel the urine to bladder
When pressure rises the utters are compressed, which prevents backflow from bladder
What is the structure of ureter? (3)
Fibrous
Smooth muscle
Transitional epithelium
What is the characteristics of the bladder?
Hollow
Sphere shaped
Muscular organ
What are the three layers of the bladder?
Outer layer of loose connective tissue
Middle layer smooth muscle layers which when contracts empties the bladder (detrusor muscle)
Inner mucosa layer (transitional epithelium)
How many opening does the base of the bladder have and leading to where?
Three
Two for the ureters and third connect bladder to urethra
Where is the bladder located?
Anterior and inferior to the pelvic cavity
What is the function of the bladder?
Store tribe
What is the adult capacity for storing urine?
500-600ml
What happens when the bladder has filled with urine?
Nerves in the bladder wall relax the sphincter allowing urine to empty into urethra
What is the urethra?
Small duct that channels urge me from the bladder to the outside wall
Where is the urethra for females?
Urethra embedded in anterior wall of the vagina behind the symphysis pubis
Where is the urethra located in males?
Urethra passes through the prostate gland, through the urogenital diaphragm and penis.
The male urethra serves as a passageway for semen as well as urine
