Questions tagged [kidney]
The kidney is an internal, bean shaped organ of vertebrates. Kidneys are responsible for secreting urine, regulate the electrolytes of the body and filter the blood.
66
questions
3
votes
2
answers
170
views
How do birds concentrate their urine?
I've read that birds have shorter loops of Henle in their kidneys, and their primary strategy of water conservation is expelling nitrogenous waste in the form of uric acid.
However, the nephrons of ...
- 43
0
votes
0
answers
29
views
Will a 5nm diameter uncharged object make it through the renal glomerular filtration apparatus in humans?
Will a 5nm diameter uncharged object make it through the glomerular filtration apparatus in humans? I think that it should as I have read that the smallest fenestrations are about 10-15nm in size and ...
- 205
2
votes
0
answers
77
views
How is the Staverman's reflection coefficient in the Stirling equation determined?
The Stirling equation is expressed as follows
$J = Kf ([Pc-Pi] - σ [πc - πi])$
Here, capillary hydrostatic pressure (Pc) and Bowman's space oncotic pressure (πi) favor filtration into the tubule, and ...
- 31
3
votes
0
answers
39
views
Does the kidney regulate sodium balance or total body sodium
Imagine the following situation. You have a person who initially eats 10 mEq/day of salt. He then, at t=0 begins to eat 150 mEq/day of Na, and will continue to do so, because you're forcing them to, ...
- 31
6
votes
1
answer
410
views
What Produces the Postive Potenial in the lumen of the thick ascending loop of Henle?
In the Thick Ascending Loop of Henle, Paracellular diffusion of certain Solutes like magnesium and calcium takes place. Such diffusion is a result of the positive lumen potential.
Looking at the image ...
0
votes
0
answers
51
views
Drinking salt water [duplicate]
I have been told that one should never drink sea water no matter how much thirsty
It turns out that drinking saltwater adds lot of salts to the body that need much more water than the amount consumed ...
- 197
0
votes
0
answers
32
views
How does the blood flow in the glomerulus when everything except plasma is drained out?
So I learned that in the glomerulus, everything smaller than the RBCs is filtered out, but I had learned previously that - Blood needs plasma, water medium to flow. So if its drained out into the ...
5
votes
1
answer
596
views
Why is ammonia converted to urea rather than secreted in the urine?
Since ammonia is highly soluble in water, my senses keep telling me something like, "Just a little bit of water is enough to flush it, given that a lot of it would dissolve per liter of solvent&...
1
vote
1
answer
330
views
Is it possible to see some renal pyramids in a transverse section those which cannot possibly be viewed in one longitudinal section at the same time?
This is just a random image I found on Google.
It is showing that, in cross-section, several renal pyramids can be viewed. Is it so?
According to the following longitudinal section of the kidney, I ...
- 23
4
votes
1
answer
230
views
How is the renal osmotic gradient maintained even though the blood osmolarity changes?
I am a high school student and I am a little confused in 2 things related to our urinary system:
We know in our kidneys a countercurrent mechanism exists due to which there is a steep gradient of ...
- 277
-6
votes
1
answer
95
views
Animal species anatomy [closed]
https://en.wikipedia.org/wiki/Animal
Do all animal species have two lungs and two kidneys similar to human beings?
4
votes
1
answer
65
views
How do organophosphates affect kidney function?
Many organophosphates, besides inhibiting acetylcholinesterase, can also permanently inhibit the enzyme neuropathy target esterase, leading to nerve damage. NTE also happens to be found in the kidneys,...
- 409
0
votes
0
answers
30
views
Why is urine acidic (equilibrium of I/O, input <=> output)
Urine pH is on average 6.0, net excretion of acid. Is that in balance with net input of acid?
- 1
0
votes
1
answer
1k
views
Why does glomerulus don't allow white blood cells to leave?
The glomerulus in nephrons are just a ball of capillaries, so why can't it allow the white blood cells to squeeze though the epithelial cells into Bowman's capsule just like the formation of tissue ...
- 33
1
vote
0
answers
93
views
How does the descending branch of the loop of Henle equilibrate concentration?
I'm learning physiology and I have a hard time figuring out how the cortico-papillary gradient is created.
Most explanations go as follow:
1) Sodium is pumped out the ascending branch into the ...
- 11
1
vote
0
answers
37
views
Vasoconstriction and blood flow
The resistance in a blood vessel is equal to the pressure difference divided by the blood flow. Let us now say that a sympathomimetic causes vasoconstriction which increases the resistance. Does this ...
- 65
4
votes
2
answers
553
views
Why is urea not converted to ammonia in the body?
After the liver processes metabolites to produce urea and other by-products, these travel in the blood to the heart, then they are oxygenated, and some travel through the renal artery to the kidneys.
...
- 327
3
votes
1
answer
54
views
Creatinine excretion
Creatinine accumulates in blood if kidneys fail to excrete it. Does this unexcreted creatinine ever get thrown out of body? What prevents creatinine from continuously rising in the blood?
Atul
2
votes
0
answers
415
views
Why is erythropoietin produced in the kidney?
Erythropoietin is a hormone produced in the kidney to stimulate the generation of more red blood cell. It is triggered by low oxygen via HIF transcription factors. Makes sense. Oops, oxygen is low, ...
- 567
2
votes
0
answers
80
views
Hematuria due to Nitric Oxide
Drug interactions between properly dosed NO and other medications are not expected, but side effects may include noisy breathing, hematuria, or possibly atelectasis. (pg.no:577; Goodman and Gilman ...
- 4,796
1
vote
1
answer
806
views
Polar renal scarring in pyelonephritis?
Why does infection and scarring occurs at poles in Vesicoureteric reflux but not in Obstructive pyelonephritis?
It is said in Robbins that, it is due to polar papillae being flattened or concave ...
- 4,796
1
vote
1
answer
143
views
Acidity and Alkalinity of Foods
Some foods leave an acidic effect on the body such as meat and dairy, while others leave an alkaline effect, like vegetables. However, are these effects significant enough to greatly alter the blood ...
- 149
0
votes
1
answer
186
views
How increased potassium intake increases sodium excretion?
"K+ antagonises the biological effects of Na+". I have been reading the same many times without any explanation. How actually (mechanism) K+ helps excretion of Na+?, their interactions? And eventually ...
2
votes
1
answer
2k
views
Do fruit juices have a diuretic effect & what governs this?
Was just contemplating this.
Juices tend to contain a lot of sugar.
Does the body absorb all the sugar in juices?
If the body does not, that sugar must be excreted by the kidneys alongside water ...
- 21
1
vote
2
answers
162
views
Is the glomerular filtration rate, per kidney or for both?
We say in a healthy human being the average glomerular filtration rate is about 120 mL/min. Is that for both kidneys together (60+60), or just one kidney?
Pardon me if this makes me sound like an ...
1
vote
0
answers
102
views
What does it mean for sodium and water reabsorption to be "coupled" in the nephron?
If sodium is transported across the tubule membrane down the concentration gradient established via the $Na^+$/$K^+$ exchanger via symport with glucose and antiport with hydrogen, and water is ...
- 11
1
vote
1
answer
85
views
Can polystyrene sulfonate bind calcium or sodium in the gut? How?
Polystyrene sulfonate is used as a potassium binder to treat hyperkalemia in traumatic rhabdomyolysis, acute and chronic kidney disease. It is listed as an ion-exchange resin that can also remove ...
- 407
2
votes
1
answer
177
views
How might IV-saline cause kidney damage that seems to be less likely with "balanced fluids" IVs instead?
The ABC News article What's in the IV bag? Studies show safer option than saline includes:
Saline — salt dissolved in water — has been the most widely used fluid in the U.S. for more than a century ...
- 5,466
2
votes
0
answers
25
views
Is there a way to remove hemoglobin from pig kidney homogenate without deactivating enzymes?
I would like to measure different enzyme activities in centrifuged pig kidney homogenate. I get out of range errors at 450 nm. The samples are still reddish after centrifugation. Is there a way to ...
- 137
2
votes
2
answers
6k
views
How does the counter-current multiplier work in the nephrons?
Why is the counter-current multiplier called like that? What is flowing in the opposite direction to the glomerular filtrate for it to be called "counter-current"?
Can you please explain the counter-...
3
votes
0
answers
2k
views
Kidney transplant and adrenal glands
When a kidney is transplanted from a donor to a recepient does the surgery occur keeping the donor's adrenal gland intact over the kidney or is the kidney minus the adrenal gland over it transplanted ...
- 1,955
0
votes
0
answers
1k
views
Does cortical nephron has just thin ascending loop of Henle?
Guyton and Hall , South Asian edition states that, in Table 76-1 that ascending limb of loop of Henle has thin segment only. But, none diagram in book or internet explain this.
Can any one explain ...
- 647
2
votes
2
answers
979
views
Why are ammonium ions reabsorbed in the thick ascending limb during acid secretion?
In order to produce HCO3- from glutamine and to subsequently reabsorb it,
H+ ions need to be secreted. The kidney does this by via ammonium ions
in the PCT. But why are the ammonium ions then ...
- 21
5
votes
1
answer
420
views
Excess protein consumption effect on kidney
How does excess protein consumption through food as well as through supplements affect body especially kidneys?
Why it is advice to consume low protein diet during summer ?
- 1,817
1
vote
1
answer
208
views
What is meant by re-absorption?
It is said that PCT, DCT, Henle’s Loop reabsorb the filtrate. Does that mean they absorb the filtrate again? If it is actually reabsorbed to medulla then why it is said that PCT, DCT or Henle’s loop ...
1
vote
0
answers
150
views
Is excess of potassium as strenuous and harmful for kidneys as excess of sodium or worst?
I was wondering since channels of body's cell membranes deal with potassium and sodium ions differently and considering the fact that potassium lowers blood pressure and sodium raises it :
What is ...
- 11
2
votes
0
answers
2k
views
Portal Systems in Humans
I was reading about nephrons in my physiology book when i came across this-
The efferent arterioles and peritubular capillaries technically constitute a portal system
But according to Wikipedia, ...
- 163
0
votes
1
answer
127
views
Does sodium lower the harmful effect of potassium on kidneys?
As far as I have read so far, it seems that potassium and sodium are trying to expel each other from the human body. A lot of documents on the web say too much sodium pressures the kidneys could cause ...
- 159
3
votes
2
answers
5k
views
Is Valerian extract a diuretic or an antidiuretic?
I am trying to determine if valepotriates (valerian extract) is a diuretic or an antidiuretic. Some individuals take valerian as an herbal supplement for anxiety disorders. Some individuals claim that ...
- 31
3
votes
0
answers
80
views
What is the evidence that mammals are unable to process excess sodium chloride?
I grew up hearing the mantra
excess salt causes heart disease
I had a vague understanding that it caused deposits in the body or something. Now that I give it more thought - I come up with three ...
- 939
0
votes
0
answers
99
views
peritoneal dialysis Vs Hemodialysis?
Their are basically two types of dialysis: 1.peritoneal dialysis 2.hemodialysis, My Question is Why the peritoneal dialysis needs to be carried out on everyday BUT hemodialysis is carried out on only ...
- 1,195
0
votes
1
answer
106
views
Diabetes Mellitus and renal failure?
I have studied that Diabetes Mellitus leads to kidney failure and that this is because of the damage to the blood vessels (especially the blood vessels in the kidney) due to high levels of blood ...
- 1,195
0
votes
1
answer
45
views
Function of human kidneys
Why are the kidneys called metanephric? What does the term metanephric actually mean? I tried to search that on Google but couldn't find the exact meaning.
- 1
2
votes
0
answers
1k
views
What is the function of the kidney in terms of osmoregulation and excretion [closed]
Also include the role that ADH plays
I am fully aware that ADH has a role in osmoregulation but does it also play a role in exretion?
- 51
1
vote
1
answer
2k
views
Find how much times blood is filtered in the kidney? [closed]
The blood that circulates in our body is about 1/12 of our mass. If the kidneys filter 7.5 liter of blood a hour, then how many times does it filter in the kidney the whole blood of a person will mass ...
- 33
2
votes
1
answer
2k
views
How do cellular waste products enter arterial blood?
I recently learned that blood in renal arteries contains waste materials, which is filtered via nephrons in the kidneys.
My question is, how are these waste materials getting into the arterial blood?...
- 31
4
votes
2
answers
7k
views
Why does the kidney of a cow have lobules, why the kidney of a human hasn't any?
The kidney of a cow has lobules, while the kidney of a human hasn't any.
I can't think of any reason why it would be good for a kidney to have lobules. It would be good if the kidney needed to have a ...
- 268
1
vote
1
answer
95
views
Is the PCT of the nephrons of the kidneys of marine vertebrates to minimize the natural tendency for exosmosis?
For marine vertebrates, the concentration of salts outside their body (in the water, that is) is more than that inside their body. So, there is a natural tendency for exosmosis to occur.
To minimise ...
- 111
1
vote
1
answer
2k
views
How does ANF increase GFR?
ANF as we know reduce the Na+ uptake and K+ removal in the distal tubules and it also functions as a Vasodialator (?) But again it says that ANF increases the Glomerular filtrate ? But if it is acting ...
- 259
1
vote
1
answer
148
views
Why is heart failure treated as more critical than kidney failure?
The heart pumps the blood to supply tissues and kidney always filters the blood to remove urea,extra water and etc. And all these are vital,so the kidney is as important as heart:
and my question is:
...
user10246