Renal system Flashcards
6 components of the renal system
Two kidneys
Two ureters
Urinary bladder
Urethra
Kidney purpose
To filter the blood
Urethra purpose
Convey nitrogenous waste substances to the outside
Three functions of renal system
Maintain normal concentration of water and electrolytes in blood
Regulates pH and fluid volume
Helps control RBC production and blood pressure
What is the area where all the nerves and blood vessels enter the kidney?
The renal hilum
Two lumps behind the kidneys
Adrenal glands
What is located retroperitoneally on either side of the vertebral column
The kidneys
What holds the kidneys in place?
Connective tissue and adipose tissue
What hollow area does the hilum lead to
The renal sinus
What are the two main regions of the kidney?
The renal cortex
The renal medulla
Functional unit of the kidneys?
The nephron
What shape is the medulla?
Petal shaped areas
What artery leads to the kidneys and where does it branch from?
Renal arteries from aorta
What vein leads from the kidney and where does it lead to?
Renal vein to inferior vena cava
Two major parts of the nephron
Renal corpuscule
Renal tubule
What is the filtering portion of the nephron?
Renal corpuscule
What is the renal corpuscule made up of?
The glomerulus and the glomerular capsule
What is the glomerulus?
A ball of capillaries
Which area of the renal corpuscule receives the filtrate?
Glomerulus capsule
What leads away from the glomerular capsule?
Renal tubule
What does the renal tubule first become?
Proximal convoluted tubule
After the proximal convoluted tubule where does the renal tubule lead to?
Nephron loop with ascending and descending limbs
After the nephron loop where does the renal tubule lead to?
Distal convoluted tubule
List in order the areas of the renal tubule
Glomerular capsule—-> proximal convoluted tubule ——> nephron loop ——-> distal convoluted tubule
What joins to form the collecting duct?
Several distal convoluted tubules from different nephrons
Which arteriole leads into the glomerulus? Which arteriole leads out of it?
In- afferent arteriole (bigger)
Out-efferent arteriole
What capillary, leading always from the efferent arteriole, runs along side the renal tubule?
Peritubular capillary
What smooth muscle cells are in the kidney?
Juxtaglomerular cells
Glomerular filtration
Fluid portion of the blood is filtered by the glomerulus and enters to glomerular capsule as glomerular filtrate
What increases pressure in glomerulus to encourage filtration?
Afferent artery larger than efferent artery
Pores in glomerular capillaries
Fenestrations
What cells help prevent plasma proteins from being filtered out of the blood?
Podocytes
Components of glomerular filtrate
Water Electrolytes Glucose Urea Uric acid
Why are plasma proteins not filtered out?
Too large
What is the movement of fluid out of the capillary caused by?
What is the movement of fluid into the capillary caused by?
Hydrostatic pressure
Osmotic pressure
What 3 factors affect glomerular filtration rate?
Glomerular plasma osmotic pressure, filtration pressure and hydrostatic pressure in glomerulus capsule
What causes filtration pressure to decrease?
Afferent arteriole constricting blood flow
What cause filtration pressure to increase?
Efferent arteriole constricting blood flow out of glomerulus
Where is renin secreted from?
Juxtaglomerular kidney cells
What does renin do?
Increase blood pressure
What happens to the efferent arteriole in response to renin?
It constricts
Where does tubular reabsorption occur?
Mostly in the proximal convoluted tubule
Why is tubule reabsorption highest in proximal convoluted tubule?
Microvilli
Carrier proteins
What substances are reabsorbed in tubular reabsorption?
Glucose
Water
Amino acids
Proteins
Which substances are reabsorbed by active transport
Amino acids
Glucose
Ions
Acids
What substance is reabsorbed by pinocytosis
Proteins
After sodium ions are reabsorbed what happens?
Water is reabsorbed by osmosis due to the change in water potential
Tubular secretion vs tubular reabsorption
Tubular reabsorption=products in renal tubule moving back into blood in the capillary
Tubular secretion=products in blood plasma moving into the renal tubule
What products move by tubular secretion?
Excess hydrogen and potassium ions
What directs urine from kidney collecting ducts to bladder?
Ureters
Three layers of the ureter wall?
Mucous coat
Muscular coat
Outer fibrous coat
Two urethra muscles
Internal urethral sphincter
External urethral sphincter
What reflex causes urine to leave the bladder
Micturition reflex
What causes the micturition reflex
Stretching of the bladder
What three muscle actions cause micturition
Destrusor muscle contracts
External urethral sphincter relaxes
Internal urethral sphincter is forced to open