Kidneys Flashcards
primary organ of the urinary system
kidneys
what are the kidneys structures
- where blood is filtered
- location where filtered material can be reabsorbed by blood
- places where waste that is not reabsorbed collects as urine
urinary system is composed of
kidneys, ureters, urinary bladder, and urethra that function the excretory process.
nephrons
structural and functional units of the kidney
kidney divided into 2 major regions
the renal cortex which surrounds an area called the renal medulla
where is the glomerulus
within the cortex of the nephron
renal cortex
the outer layer of the kidney
renal medulla
the inner most part of the kidney
glomerulus
a network of capillaries from which blood pressure pushes water, salt, glucose, amino acids, and urea from the blood
filtrate
contain materials including water, that leave the blood through the walls of the glomerular capillaries to enter the Bowmans capsule
proximal tubule
where glucose and other useful solutes are reabsorbed back into the blood through the walls of surrounding capillaries.
loop of Henle
also site of reabsorption
distal tubule
site of reabsorption
tubular reabsorption
movement of useful material from filtrate back into the blood stream
renal pelvis
the center of the kidney where urine collects before moving to the ureter
primary function of the kidney
- to filter metabolic waste from blood
- regulate electrolyte and fluid balance in the blood
- affects blood volume from fluid balance influence. Resulting in changes in blood flow rate and blood pressure.
osmosis
movement of water
renal artery
artery going into liver
renal vein
blood exits liver through renal vein
blood pressure in glomerulus
generally held constant regardless of systemic blood pressure.
what byproducts must be kept a low levels in blood
urea, uric acid, and creatinine
what is water lost in urine influenced by
amount of sodium chloride (NaCl) in the blood. Sodium ions lead chlorine atoms
what is water reabsorption dependent on
osmotic pressure
dehydration causes
reduced blood volume, lowering blood pressure as a result
renin
an enzyme released by the kidneys when reduced blood pressure is detected by baroreceptors in aorta or carotid arteries
aldosterone
a hormone secreted by the adrenal gland that increases reabsorption of sodium ions which leads to the reabsorption of chlorine ions and water into blood mainly in the distal tubule. Increases blood pressure
how is blood pressure detected
by baroreceptors in aorta and carotid arteries
renin creates
angiotensin I from angiotensinogen.
angiotensin
a protein whose presence in the blood promotes aldosterone secretion, vasoconstriction, and tends to raise blood pressure.
angiotensinogen (mRNA)
synthesized in liver and is split by renin to produce angiotensin I (inactive).
Angiotensin II
a secretion that acts to restore blood volume and blood pressure by contracting blood vessels, stimulating thirst, and stimulating production of aldosterone and antidiuretic hormones. Ultimately causes an increase in blood pressure.
Made in blood by circulating proteins
antidiuretic hormone
secreted by the pituitary gland that increases the amount of water able to be reabsorbed back into the blood from a collecting duct. Increases blood pressure
blood pressure increases by
increasing blood volume
what happens if blood pressure drops
kidneys release renin which stimulates the production of angiotensin II ( which also triggers release of Antidiuretic hormone (ADH) and Aldosterone) which results in a raise in blood pressure directly causing vasoconstriction.
