Renal Flashcards
kidney function
act as filters to clean the blood, making urine by taking waste products out of your blood
what is selective reabsorption
useful substances like glucose,some ions, and the right amount of water are reabsorbed back into the blood
what substances are removed from the body by urine
urea, ions, water
what is urea
ammonia is converted into urea by the liver to be filtered
where is ammonia made
ammonia is a waste product of deamination
what is deamination
proteins broken down into ammino acids, excess ammino acids are converted into fats and carbohydrates which occurs in the liver, the waste product is ammonia
what is the purpose of anti diuretic hormone
the concentration of urine is controlled by adh
where is ADH made
pituitary gland
renal system comprises of
two kidneys two ureters, one bladder, one urethra
location of kidneys
retroperitoneal
size of kidneys
12cm x 6cm x 3cm
functions of the kidneys on volume
maintain Volume of fluids within the body
metabolic processes are controlled by the kidneys
gluconeogenesis - if our body has ran out of sugar, we can use fats and proteins in the kidneys for energy
- glycogenesis -storage of glucose
- glycogenolisis - breaking apart the stored glycogen to use
- vitamin d synthesis - last step in the process (controlling ca level)
concentration affects from kidneys
concentration of ions within the body, sodium, potassium, chloride, mg, hydrogen, bicarb, calcium
kidneys effect on the pH
kidneys help regulate long term acid balance by altering the concentration of ions
excretory effects by the kidneys
removes waste i.e. urea , creatinine, drugs , toxins
what types of drugs can the kidneys remove
water soluble
endocrine function of the kidneys
renin
erythropoietin
how much CO goes to the kidneys
20%
renin angiotensin aldosterone system is activated when
our volume drops within the body, dropping bp
how many nephrons per kidney
1million
where does most of the nephron sit in the kidney
cortex
the loop of Henle and the collecting ducts sit where
in the renal pyramid/medullary pyramid
what happens in the afferent arteriole
it brings blood in to the glomerulus
function of the glomerulus
main filtering unit of the kidneys
what is the sac called that covers the capillaries in the glomerulus
bowman’s capsule
what is the glomerular filtration rate
120ml/minutew
what is the stimulus to produce renin
if the glomerular filtration rate drops below 120ml/min due to loss of blood or volume
where is renin released from
in the afferent arteriole
what are the cells that are responsible for releasing renin called
renin releasing granular cells or juxtaglomerular cells
what type of substance is renin
its an enzyme
how do the granular/juxtaglomerular cells know to release renin when the volume drops within the system
the cells have barrow receptors which identify a drop in blood pressure
when the bp drops what happens to the sodium as its being filtered
there is more time for reabsorption of na as the filtrate is going through slowly, therefore more sodium gets reabsorbed back into the body
what process happens after a bp drop in the distal convoluted tubule
if the sodium levels drop when reaching the DCT as there has been excessive reabsorption the macular densa cells identify this
macula densa cells measure what
concentration, chemo receptors
macula densa cells are connected to what
connective tissue, next to the granula cells in the afferent arteriole
3 different ways that renin is triggered into the body
low bp in the afferent arteriole
low sodium in the DCT
increased sympathetic nervous system innovation (fight or flight) stimulates the granular cells
once renin is released from the kidneys into the systemic circulation, what is the next step
angiotensinogen in the liver is released into the blood stream, comes across the enzyme renin and it becomes angiotensin 1
where is angiotensinogen stored
liver
what impact does antiogensin 1 have on the systemic circulation
none alone, mild vasoconstrictor
what is the importance of the lungs in the RAAS
the lungs produce an angiotensin converting enzyme (ACE)
what is the effect of angiotensin convering enzyme (ACE) on angiotensin 1
it converts it to angiotensin II
what effect does angiotensin II have on the body
generalised vasoconstrictor , constricts arterioles - incr bp
travels to the efferent arteriole and constricts the efferent arteriole , increasing the filtration rate in the glomerulus (inc. GFR)
where does the angiotensin II travel to
the adrenal gland (the cortex) and stimulates the release of aldosterone
what function does the adrenal gland (cortex) have in the RAAS
aldosterone is released, travels to the DCT and retains more sodium into the body , incr. na absorption
what function does the hypothalamus have on the RAAS when angiotensin II is active
hypothalamus tells posterior pituitary gland to release ADH
ADH effects where
DCT and collecting ducts, instructing them to reabsorb more water into the body
