keeping homeostasis in water balance (osmolarity)
-cell respiration: glucose + O2 –> ATP CO2 + H2O
-gets rid of excess nitrogen “metabolic waste”
-cell respiration: glucose + O2 –> ATP CO2 + H2O
-gets rid of excess nitrogen “metabolic waste”
Excretory system
H2O out
-too low solute
-too low solute
Hypertonic
H2O in
-too much solute
-too much solute
Hypotonic
H2O out and in
-animal cells
-animal cells
Isotonic
cells = hypertonic (saltier)
-hypotonic H2O flood into fish
Problems:
-flooding of H2O in
loss of salt (ions) out
Solutions:
-get rid of H2O in urine
-add salt in gills
-no need to drink
-hypotonic H2O flood into fish
Problems:
-flooding of H2O in
loss of salt (ions) out
Solutions:
-get rid of H2O in urine
-add salt in gills
-no need to drink
Freshwater fish
cells = hypotonic
-hypertonic water (saltier) so H2O flood out of fish
Problems:
-dehydration (water loss)
-gaining ions
Solutions:
-drink (gain ions)
-pump out ions @ gills
-little urine
-concentrated to save H2O
-hypertonic water (saltier) so H2O flood out of fish
Problems:
-dehydration (water loss)
-gaining ions
Solutions:
-drink (gain ions)
-pump out ions @ gills
-little urine
-concentrated to save H2O
Saltwater fish
amino groups, waste
Animals have extra _______ so _____ becomes toxic
kidney
renal =
guano
uric acid =
blood
-urea and water = urine
-urea and water = urine
kidney filters ______
exit of bladder out of body
urethra
outer layer of kidney
cortex
inner layer of kidney
medulla
urine
-by filtering blood
-remove urea
~get rid of it with little water as possible
-by filtering blood
-remove urea
~get rid of it with little water as possible
Nephrons make ______
glomerulus, 25%
-big stuff is blocked: cells, proteins
-small stuff gets into nephron: H2O, urea, ions, Na, Cl, K, glucose
-big stuff is blocked: cells, proteins
-small stuff gets into nephron: H2O, urea, ions, Na, Cl, K, glucose
Blood pressure pushes blood into ________ and about ____ plasma enters into Bowman’s capsule inside the nephron
strainer/filter
1) Glomerulus
rescues good solutes (H2O, ions, glucose, and vitamins) from filtrate by reabsorption –> go to vasa recta back into the blood stream
2) Proximal convoluted tubule
reabsorb ions, glucose, vitamins, H2O and just dumps urea for waste
Nephrons
set up a solute gradient in the medulla. Deep in medulla, more hypertonic (saltier) (4 solute)
3) Loop of Henle
-concentrates urine, water is pulled out by the salty (high solute/high osmolarity) medulla
-water leaves collecting duct, urine is concentrated
-concentrates urine before it goes to ureter –> bladder –> urethra
-water leaves collecting duct, urine is concentrated
-concentrates urine before it goes to ureter –> bladder –> urethra
5) Collecting duct
last chance to get ions reabsorbed
4) Distal connective tissue
run along the loop of Henle in the countercurrent fashion
-blood exits merge to renal vein
-blood exits merge to renal vein
Blood vessels called the vasa recta
glomerulus
Where does the filtration step occur in the human kidney?
blood pressure
What is the force that causes up to 25% of the blood’s plasma volume that arrives at the glomerulus to enter into the Bowman’s Capsule and become the pre-urine filtrate?
The pores at the glomerulus are too small for them to pass through
Why don’t blood cells and large molecules enter Bowman’s capsule?
The proximal convoluted tubule
Where in the nephron does the majority of water and solute reabsorption occur?
Both ADH and Aldosterone will be produced. ADH will trigger increased water absorption in the collecting duct and DCT and Aldosterone will increase Na uptake in the DCT which will increase replacement of lost salt, increase blood osmolarity, and will draw in water into the blood vessels to keep blood volume normal. Together ADH and Aldosterone work to keep blood osmolarity and volume normal and prevent dehydration. In addition, the hypothalamus will likely trigger thirst and encourage water input through drinking
After a good workout you have sweat out a considerable amount of water and salt… how will the body’s osmoregulation be affected?
They would need to drink a lot of water to compensate for water loss
Biologists have recently been able to produce mice that lack functioning genes for making aquaporins. How does their urine compare to that of individuals with normal aquaporins? How should the biologists feed and water these mice to keep them most healthy?
-diuretic = increase volume of urine, lot’s of dilute urine is made
-ADH = concentrate urine, saves H2O
-when ADH is present- collecting duct has lots of aquaporins
~let H2O more in/out of collecting duct
*water LEAVES b/c medulla is very salty –> sucks H2O out
~fights dehydration
-ADH = concentrate urine, saves H2O
-when ADH is present- collecting duct has lots of aquaporins
~let H2O more in/out of collecting duct
*water LEAVES b/c medulla is very salty –> sucks H2O out
~fights dehydration
ADH (Anti- diuretic hormone)
-collecting duct has lots of aquaporins
~let H2O more in/out of collecting duct
*water LEAVES b/c medulla is very salty –> sucks H2O out
~fights dehydration
~let H2O more in/out of collecting duct
*water LEAVES b/c medulla is very salty –> sucks H2O out
~fights dehydration
When ADH is present. . . collecting duct has lots of
no aquaporins in collecting duct- water stays- urine is dilute
When ADH is absent. . .
-salty meal
-dehydrated
-dehydrated
Why is blood osmolarity too high?
ADH turned off –> urine is dilute
Why is blood osmolarity too low?
hormone in kidneys that helps with reabsorption/conservation of water, acts on distal tubules
Aldosterone
-blood: kidney stones, hyper tension, physical trauma, kidney infection, UTI (bateria in bladder)
-proteins (same as blood)
-drugs
-glucose: in urine, sign of diabetes
~very high blood sugar –> Insuline issues
-proteins (same as blood)
-drugs
-glucose: in urine, sign of diabetes
~very high blood sugar –> Insuline issues
Urine test checks for
-form when your urine contains more crystal-forming substances than the fluid in your urine can dilute.
types:
1) calcium (most common)
2) uric acid (more common in men than woman, urine is too acidic)
3) struvite (more common in women than men, UTI)
4) cystine (rare, genetic disorder cystinuria)
types:
1) calcium (most common)
2) uric acid (more common in men than woman, urine is too acidic)
3) struvite (more common in women than men, UTI)
4) cystine (rare, genetic disorder cystinuria)
Kidney stones
-occur b/w ages 20 and 40
-caucasians more likely than african americans
-more men than women
1. dehydration
2. obesity
3. high-protein, salt, or glucose diet
4. gastric bypass surgery
-caucasians more likely than african americans
-more men than women
1. dehydration
2. obesity
3. high-protein, salt, or glucose diet
4. gastric bypass surgery
Risk Factors for Kidney Stones
