Questions tagged [homeostasis]
The maintenance of a constant internal environment - for example temperature, carbon dioxide concentration or water concentration, etc. within an organism.
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Why do you die if you cannot breathe?
I was wondering what the actual reason for death by suffocation is. Obviously it is related to oxygen deprivation. But what is the underlying cause of death?
Is it due to insufficient oxygen for ...
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If body temperature is 37°C (98.6°F), why are most people more comfortable at around 21°C (70°F)?
It may be different for other people, but for me, anything above 32°C (90°F) is very uncomfortable, and my body is inclined to seek cooler temperatures. But I would think that at 32°C, the body would ...
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What biological functions does crying serve?
Tears suddenly start flowing out of our eyes when we find our long lost friend or when someone unexpectedly decides to break up with us. Do tears really save us from harm? Or are they just the reflex ...
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Glomerular Filtration Rate
In practice, when you have vasoconstriction of the glomerular capillaries and subsequently an increase in blood pressure, glomerular filtration rate increases. However, this seems counterintuitive to ...
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Is lemon water an alkalizing agent in the body?
I was recently having a discussion with someone about whether lemon water actually increases the pH of your body (by which I assume they mean the blood); their claim was that once Citric acid was ...
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Last-ditch efforts to maintain thermal homeostasis
I was in the gym's steam-room today and a thought occurred to me: have I truly thwarted all possible mechanisms for maintaining thermal homeostasis?
There's sweating, which is thwarted because the ...
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How does the body measure dehydration?
What, physically, does the body do to measure it? I assume it's measured by how how turgid or plasmolysed certain 'sample cells' are, or water concentration in the blood,
What is the way they use to ...
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Why antipyretics do not bring the body-temperature below normal?
Antipyretics like paracetamol are used to decrease the body-temperature in fever patients.
But some of them are also used as pain-killers in sprain or other injuries (where there's no fever). In ...
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Can tardigrades survive being eaten?
Compared to a tardigrade, the cockroach seems fragile.
But can tardigrades survive the acidic environment of being eaten by most animals?
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Why do people feel extreme cold at different temperatures compared to other people of same body structure?
I have seen some people shivering in the room temperature of 18°C while others of similar body structure do not feel that much amount of cold.
Of course the clothing of both people is similar if ...
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Counterintuitive action of Vitamin D?
Vitamin D acts in a way which to me is counterintuitive. It functionally supplemets Parathormone. It in the intestinal tract steps up calcium absorption by altering nuclear gene expression and also ...
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How can hyperthyroidism induce osteoporosis?
It says in my physiology notes that hyperthyroidism can cause osteoporosis.
I've been trying to figure out how this could be possible for a little more than an hour now. Every article that I look at ...
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At what calcium concentration does the Sodium-Calcium Exchanger (NCX) "turn on"?
I am interested in the comparison between the Plasma Membrane Calcium ATPase (PMCA) and the Sodium-Calcium Exchanger (NCX) which are two pumps on the plasma membrane of cells that serve to move ...
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How does the brain cool itself?
Thoughout life everyone tells you that brain is essentially a computer but just like computers your brain would create immense amounts of heat by being in use, so if that's the case how does it cool ...
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why do our eyes not go red in response to body temperature?
I know that blood flow increases/decreases in response to temperature change, which is why (lighter-skinned) people go red when they are hot.
I know that the eye contains lots of blood vessels.
Why ...
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How do poiklotherms survive at different temperatures even though enzymes work at specific temperature?
Since enzymes have an optimum temperature at which they are able to catalyze the reaction best and increasing the temperature above optimum can even damage them, how do poikilotherms survive as they ...
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Human leukocytes (re)circulation/migration in homeostatic state
One can easily find information on the topic of leukocytes trafficking between vessels and peripheral tissues during inflammation.
But what happens during normal states when there is no pathology? ...
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Why do we get sleeply after we eat?
After we have eaten, we feel cold and sleepy. I think it's because the maximum blood supply is transferred towards the digestive system so that digestion is done, and therefore the brain to does not ...
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Euthyrodism and goitre
I read in Tortora and Derrickson that goitre is associated with euthyrodism.
How is that possible?
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Do river sharks (genus Glyphis) have reduced rectal glands for salt removal?
Do river sharks of the genus Glyphis have reduced or absent rectal glands for salt removal?
The rectal gland of marine sharks removes excess salts to maintain osmotic balance (Oguri 1964). In ...
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Hypothalamus and posterior pituitary gland in ADH production
Concerning the role of hypothalamus and the posterior pituitary gland in osmoregulation and especially when water potential of the blood is low,
When the osmoreceptors in the hypothalamus detect the ...
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What is enantiostasis?
I have searched around and read my textbook but I am failing to understand how enantiostasis is different to homeostasis. For reference, Wikipedia definition is as follows:
Enantiostasis is the ...
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Why do endotherms need more food than ectotherms?
I have a rough idea: endotherms need more food to keep their temperature stable whilst ectotherms use less of their food in respiration.
but that's just me parroting the textbook I don't really ...
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Can oral baking soda effect tumor cells in mice
Could anyone explain me please, how exactly (according to research article in Cell journal) adding the baking soda in drinking water can influence the acidity of tumor cells? What about homeostasis ...
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Osmolarity vs. Tonicity
We're learning about osmoregulation in AP Biology and the terms Tonicity and Osmolarity are really confusing me. I watched this video on Khanacademy to try to understand what the difference is, and ...
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Blood pH at Higher Altitudes
My Campbell's Biology Textbook says the following:
"For example, when an elk or other mammal moves up into the mountains from sea level, physiological changes that occur over several days ...
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Hibernation in ectotherm and endotherm
Both snake and weasel hibernate. Which of the following is correct?
A. They will die when temperature decreases below the critical
temperature.
B. Weasel will die when temperature ...
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Does all CO2 from the blood leave the body through the respiratory system?
I know that the primary way that CO2 leaves a healthy human’s body from the blood is by diffusing into the lungs during gas exchange and then being exhaled. Is there any other way in which CO2 from ...
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What's the feedback regulation of Thyroid diseases and body temperature?
While going through the feedback regulation, the control of blood glucose level by insulin and glucagon is quite discussed in multiple materials including the textbook. I also understand the basic ...
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Darwinism and the idea of being too successful
Is there an example of any animals or insects that have evolved too efficiently and went extinct due to upsetting the homeostasis of their environment? Outside humans.
I was thinking about venomous ...
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Regulation of the TCA cycle and glycolysis by adenine nucleotides
Why is the tricarboxylic acid cycle regulated by the ADP/ATP ratio as stated in the following quote :
Isocitrate dehydrogenase is allosterically stimulated by ADP, which enhances the enzyme's ...
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How does the brain regulate its temperature?
I recently ran into a bio-physical paradox while trying to solve an engineering problem, using nature's way as a guide; namely the brain.
I'm working on designing a totally new system of liquid/gas ...
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Giving diuretics to insipidus patient
I read in Tortora and Derrickson that giving diuretics to diabetes insipidus patients may in fact alleviate the symptoms of the disease. How is this possible?
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Are there any benefits/disadvantages/traits from having a permanent lower core temperature?
My body temperature as far as I remember has always been around 35.6 degrees Celsius, that's a degree less than what is the usually quoted as the average temperature for humans.
Are there any known ...
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Role of the Hypothalmus in the control of Blood Sugar
In homeostatic regulation of blood glucose, the receptor and effector is the Pancreas, but how does the control centre — the Hypothalamus — connect and link into this process?
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Regarding cancer cells and radio-frequency ablation
Are cancer cells destabilized if near a strong electromagnetic field over a long period of time? I read this technique of using radio-frequency ablation and heat shock to kill cancer cells. I don't ...
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How do the maximum rates of calcium pumping compare between the calcium ATPases SERCA and PMCA
Two important Calcium ATPases found within cells are the Sarcoplasmic reticulum Ca2+ ATPase (SERCA) and the Plasma membrane Ca2+ ATPase (PMCA). Both use ATP to help maintain resting calcium ...
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Does bone resorption cause alkalosis?
The phosphate in hydroxyapatite Ca5(PO4)3(OH) is a strong base, PO4^3-, and the hydroxide is also a base, OH-. I was talking with a biologist the other day about if bone resorption (at a level that ...
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Dangers of excess blood protein? [closed]
Like glucose, amino acids are also insulinogenic as well. So, presumably, just like glucose, the body would also like to keep amino acids levels in the blood stream below (or within) some certain ...
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Is there a homeostatic setpoint for number of hours of sleep required by a human?
I've heard this TED.com talk about dieting and it mentions that there's a very definitive setpoint within the human brain about how much a human should weight. The speaker mentions that after as much ...
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Why don't cats have to pant?
I understand why dogs pant and humans transpire, namely for temperature homeostasis. So why don't cats need to do either, even after expending a lot of energy on a hot day?
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Hypothalamic breakdown and effect of temperature on membrane lipids
I'm in my last year of high school and doing a research assignment on thermoregulation. In the excellence level exemplar for the standard, a student made the statement:
Once the body's internal ...
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Does sleep schedule affect circadian rhythm?
During the circadian rhythm, the internal human body temperature supposedly peaks around 4-6 pm. Let us assume that the average person goes to bed around 11 pm and sleeps for 8 hours. In that case ...
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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 ...
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Has the concept of allostasis been adopted in biology, in place of homeostasis?
Peter Sterling, among others, has been a prominent critic of the concept of homeostasis. He instead proposes a process called allostasis.
Homeostasis involves having fixed set points for ...
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