excretory system Flashcards
excretion
getting rid of materials from the body
secrection
moving materials from one place inthe body to another
example of a body part that secretes
liver, pancreas (hormones)
example of excretes
sweat, urine, tears, vomit
organs involved in sweating
sweat glands
organs involved in urine
bladder, kidneys
organs involved in tears
tear ducts
organs involved in vomit
stomach
organs involved in feces
rectum
three main processes in excretory system
- filtration
- reabsorption
- secretion
filtration
the selective movement of materials from the blood (glomerulus) into the nephron (kidney)
reabsorption
movement of materials from the nephron (kidney) back into the blood
-opposite of filtration
process of secretion
the movement of materials from the blood into the kidney part after filtration has happened, in the process of making urine
main organs of excratory system (4)
kidneys, ureter, urethra and bladder
renal
kidney
nephron
functional part of the kidney
- beige tube
- high pressure
- reabsorbes valuable nutrients back into the body
glomerulus
wound up capillary
- high pressure (55-60)
- pushes whatever it can into bowmans capsule
what is key to a kidney working
blood pressure
afferent arteriole
entering glomerulus
efferent arteriole
exiting glomerulus
bowmans capsule
wrapped around glomerulus
-site of filtration
proximal convoluted tubule
-closer to bowmans capsule
proximal
closer
dismal
distance
convoluted
complicated (twisty)
collecting duct
urine found inside
why are blood cells and proteins found in the filtrate
Proteins and red blood cells are not found in the filtrate because they are too big to fit in the capillary process of filtrating
Why are useful molecules like glucose and other nutrients found in the filtrate along with urea and other wastes?
The glucose is small enough to be filtered out into the urea, but then can be reabsorbed very quickly into the blood stream, since it is so valuable
One of the effects of a drug overdose is a serious decrease in blood pressure. How might this affect kidney function?
The kidney wouldn’t filter as properly, and the amount of filtrate would drop, meaning not all waste would get out of the body.
deamination
removal of an amino group, that is turned into ammonia
urea
combination of ammonia and carbon dioxide (less toxic)
metabolic waste
- CO2
- Na
- Cl
- H
- NH3 (most toxic)
if metabolic waste becomes too….
concentrated in the body, they can have toxic effects
ammonia
toxic to cells
producted during the breakdown of protein
building blocks of proteins
amino acids
essential amino acids
amino acid needed to get from our diet
hydrolysis
breaking up peptide chains
- reactant and water
- NEEDS WATER
what turns ammonia to urea
liver, which combines ammonia with carbon dioxide
urea is excreted by the
kidneys
deamination
process of ammonia being converted to urea
-less toxic allows us to survive
uric acid
breakdown of dna
-much less concentrations also excreted by the kidney
urine formation starts in the
kidneys
difference in female and male urinary tract
females - urethra is shorter, only carries urine
males - urethra is much longer, carries sperm and semen
urinary tract infections are more common in
females, because its a shorter urethra and bacteria can get in easier/quicker
coretx
outer layer of the kidney
medulla
iner workings of kidney
nephron is found
renal cortex and renal medulla
loop of henley heads down into
the medulla
collecting duct takes urine into
renal pelvis then to the ureter
renal pelvis
iner iner kidney
the four main processes of urine formation
- glomerular filtration
- tubular reabsorption
- tubular seretion
- water reabsorption
glomerular filtration
from the blood into the nephron
-glomerulous into bowmans capsule
how much filtrate a day does our body produce
120L
tubular reabsorption
removes the useful substances from the filtrate and returns them to the blood for reuse
the kidneys are very much focused on
homeostasis
glomerular filtration arrows
down from blood flow into tubule
tubular reabsorption arrows
out from tubule into capillary/blood flow
tubular secretion
adds wastes from the blood to the filtrate after bowmans castle
water reabsorption
removes water from the filtrate and returns to the blood
-reabsorption especially for water
tubular secretion arrow
from capillary into tubule
water reabsorption arrow
from tubule to capillary etc
why is there so much filtrate being formed
the glomerulous doesn’t think as it is pushing all the filtrate it can no matter how important
bulk flow
forcing all the particles it can fit
active transport
going from low concentration to high concentration against the concentration gradient
-uses ATP
tonic
amount of solute
hypertonic
lots of solute
nutrients reabsorbed by the blood
sodium, potassium, glucose and amino acids
active transport out of proximal tubule
NaCl, nutrients
passive transport out of proximal tubule
HCO3, H2O, K
secretion into nephron
hydrogen (for pH) and ammonia
descending loop is major for
dealing with water, putting more water into the blood
what part of the kidney is impermiable to everything but water
descending loop of henle
concentration of salt in inner medulla
higher, due to the water leaving during descending loop of henle
ascending loop is major for
salt balance, NaCl is diffused out
where is salt loss the most major
ascending loop of henle, starting with passive transport then leding to active transport
distal tube is major for
fine tuning the bloods content
most fine tuning takes place in
distal tube and collecting duct
typically what is inside urine
- uric acid
- bicarbonate ions
- creatinine
- potassium
- sodium, chloride
- urea (alot)
- water(the most)
largest portion of urine
water
bicarbonate ions will
increase the blood pH
dehydration
not enough water in the blood
ADH stands for
anti diuretic hormone
ADH
a hormone that allows the distal tubule to reabsorb water
- through aquaporins
- into the blood stream rather than peed out
- without this hormone the distual tubule cannot reabsorb water
what part of the body creates feeling of thirst
hypothalamus
aquaporins
proteins in the kidney that reabsorb water into blood stream
-get more aquaporins with ADH
alcohol/coffee and ADH
blocks ADH and makes no reabsorption of water take place, thus needing to pee immediatly
osmoreceptors
looking for lack of water
-found in hypothalamus
pituitary gland
where ADH is secreted
-hypothalamus activates this
dehydration NFBL
- hypothalamus osmoreceptors signal low water levels in the blood
- activates pituary gland
- releases ADH
- ADH allows nephron, distal tubule to be semi permeable and reabsorb water into the bloodstream and not into our urine
what part of the nephron does ADH target
distual tubule
JGA
little sensoyrs in the afferent arteriole
- sensing blood pressure
- sends out enzyme renin
angiotensin pathway
comes from the liver
- singaled by renin/JGA
- allows body to deal with low BP
angiotensin-what does it do
- constricts blood vessels
- releases aldosterone
low blood pressure due to fluid levels NFBL
- JGA senses low BP
- releases enzyme renin
- renin activates angiotensin
- angiotensin restricts the blood vessels and releases hormone aldosterone
aldosterone
a hormone from the adrenal glands (on top of the kidney)
- targets the distual tubule/collecting duct
- allows salt to be reabsorbed into the blood
why would aldosterone send salt into low BP
with salt follows water, which would increase blood pressure
diabetes insipidus
uncommon, body does not produce ADH
- insufficent ADH production
- dilute urine, 8L a day
- may be treated with synthetic ADH
cortex
outside
medulla
middle
renal pelvis
hollow inner chamber which funnerls urine to the ureter
where does reabsorption and secretion take place in the kidney
cortex and medulla
source of ADH
posterior pituitary gland
source of aldosterone
aldrenal glands
ADH target
collecting ducts and distal tubule membrane
aldosterone target
collecting ducts and distal tubule membrane
ADH is relased when
hypothalamus detects low water levels in the blood and shrink due to rising osmotic pressure
aldosterone is relased when
JGA detects low blood pressure and releases enzyme renin which activates hormone aldosterone or constricts vessels
ADH affects on the kidney
causes aquaporins in nephron to open, increasing reabsorption of water into blood
aldosterone affects on the kidney
creates more salt reabsorption which moves water also into the blood
final result of ADH
concentrated urine and more water in the blood
final result of aldosterone
blood pressure is restored, concentration is higher in urine, more water in the blood
diabetes
excess urine formation
-peeing way more than you should
what causes diabetes insipidus
not enough ADH created, peeing up to 16L a day
what type of diabetes causes you to pee out glucose
diabetes mellitus
what is the importance of insulin
allows glucose to get into cells
What type of diabetes do you have if insulin is not produced?
type 1 diabetes, where genetically you do not produce insulin
What type of diabetes do you have if insulin is produced but does not work properly?
type 2 diabetes, where overtime due to diet you cannot properly use insulin made
type 1 diabetes
pees alot to release high amounts of glucose in the bloodstream, looses water in the process
symptoms of diabetes
- slow healing
- infections
- urination
- dehydration
- blurred vision, can get blind
- weight loss
- tiredness
type 2 diabetes
insulin spots are filled with fat/doesn’t work properly
-high insulin levels, that eventually wear out
nephritis
inflammation of the nephron
urinary tract infection
- bacteria or viral
- painful frequent urination
- affects more woman than men
kidney stones
excess calcium in urine, forms into little hard rocks
- formed in renal pelvis, blocks ureter
- pressure build up in the kidney, extremely painful
dialysis
low or no kidney function
hemodialysis
uses an artificial membrane to filter out the blood
peritoneal dialysis
catheter is surgically inserted into the abdominal cavity
dialysate
pure water, that filters blood out
ions are solely transported by active transport in this section of the nephron
distal tubule
glucose in the urine, extreme thirst, and fatigue might indicate this diease
diabetes mellitius
to move substances out of the body
excretion
blood plasma moving into the nephron
filtration
out of the blood and into the nephron
secretion
the removal of an amino group from a protein
deamination
form the mid section of the kidney
medulla
these capillaries wrap themselves around the tubule of the nephron
peritubular capillaries
this part of the nephron only works under high pressure
bowmans capsel/glomerulus
these organs are the site of excretion
kidneys
this hormone adjusts water homeostasis by making the distal tubule more permeable to water
ADH
urine with blood proteins in it might be the result of this diease
nephritis
maximum amount of a substance has moved across the nephron
threshold level
this blood cleaning technique makes use of the linings of the internal organs
peritoneal dialysis
these calcium deposits form in the kidneys and will need to be passed
kidney stones
tube responsible for transport of urine out of the body
urethra
these tubes connnect to the distal tubule and lead out of the nephron
collecting duct
most commonly concentrated solute found in the collecting ducts
urea
energy compound is immediately reabsorbed in the proximal tubule
glucose
85% successful procedure might be in trouble if the immune system doesn’t cooperate
kidney transplant
its all about water reabsorption here
descending loop of henle
functional unit of the kidney
nephron
hollow area of the kidney that joins ureters
renal pelvis
this ion is secreted in order to control blood pH homeostasis
hydrogen
ion actively transported out of the nerphron Cl and water soon passively follow
Na
