The study of the normal function of living organisms and the means by which it is achieved.

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93 views

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 ...
6
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1answer
133 views

Which organs in the body are responsible for measuring temperature?

As an instrumentation engineer, I have designed temperature control systems capable of measuring and controlling temperature with a precision of 0.001K over a wide temperature range. I have always ...
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1answer
289 views

Why do mice have a higher metabolism?

Mice and other small animals have higher metabolic rate than humans. How does that happen on cellular level, if we look on one cell in the mouse body? What is it in this cell that will be ...
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1answer
58 views

Unable to identify a muscle of the anterior thorax

I was watching an YouTube Anatomy Video which goes over the major muscles of the anterior superficial thorax. There is a structure present throughout the video which goes unmentioned, and I can't seem ...
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2answers
4k views

Difference between facilitated diffusion and secondary active transport in cells

Specifically, what is the difference between facilitated diffusion carrier processes (passive transport) and secondary active transport co-transport processes (active transport)? They seem to be the ...
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2answers
564 views

When glucose production is low, the brain begins using ketoacids as energy… how does that work?

Can someone very generally describe how the brain consumes ketoacids/ketone bodies when blood glucose has been completely depleted?
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1answer
155 views

Why do people in the scientific community use terminology such as renal, hepatic, cardiac instead of kidney, liver and heart? [closed]

Are there differences between renal, hepatic, cardiac and kidney, liver and heart? Is the "jargon" used more commonly because of tradition, or is there some definitive biological basis to it?
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27 views

Why doesn't EMG data for triceps show a clear relationship?

In a surface electromyography (EMG) experiment of the triceps muscle where a person lifts weights, I found the value for maximum amplitude of EMG signal to be rather similar for all loads of 0-10kg. ...
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4answers
376 views

Resilience to the neurotoxins of Indian King Cobra

I read on Wikipedia about this: King Cobra - Wikipedia In Thailand, a concoction of alcohol and the ground root of turmeric is ingested, which has been clinically shown to create a strong ...
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1answer
405 views

Is it true that cats can drink sea (salted) water?

Found somewhere in the Net, that cats can drink sea (salted) water. This fact seems to me as being urban legend, not true (because the purpose of water in body apparently implies it should be clear). ...
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1answer
95 views

Loss of appetite during fever

It is a well-known phenomenon that sickness like the common flu is often accompanied by reduced appetite. Why do sick people stop eating?
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0answers
17 views

How to use the law of diffusion in the presence of electric forces?

Isn't the movement of ions affected by the electric field as well? For instance, when a sodium channel in a cell's membrane opens, the sodium ions are said to diffuse into the cell, from higher ...
3
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1answer
37 views

classical conditioning paradigm for hippocampal learning

I wanted to know what a suitable classical conditioning experiment would be to analyze learning and memory capabilities in rodent models with respect to hippocampal long-term potentiation. For ...
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69 views

Is there a lower temperature limit, below which we cannot sense a difference in temperature?

At work I have to handle samples stored at -20 and -70 degrees Celsius, and they don't feel that different to me.
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2answers
79 views

What causes goose bumps?

What is the actual process and reflexes that cause the goose bumps? Why is it an evolutionary advantage to have goose bumps in the first place?
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1answer
25k views

What is the normal duration of human sexual intercourse?

Wikipedia is saying: Men's typical ejaculatory latency is approximately 4–8 minutes How the researchers measured this? How did they know if the test subjects weren't suffering from premature ...
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1answer
54 views

Wheatgrass in thalassaemia

In local newspapers there was a not so recent story about wheatgrass juice being "curative" in thalassaemia. Although I do not take the article at face value, it would be enlightening to know if there ...
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1answer
194 views

Why do animal cells lack a contractile vacuole?

I was asked why animal cells do not have contractile vacuoles. Other than the lack of need, I don't know what else to say.
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1answer
47 views

Determining the osmolarity and tonicity of a cell

Consider a cell with urea concentration inside being 2mmol/L and outside being 2.5mmol/L. The cell itself is permeable to both urea and water. Ignoring the effect of other osmolytes, A) Urea flows ...
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0answers
26 views

What are the molecular/cellular basis of pruritus ?

Could someone please explain the cells and molecules involved in the clinical phenomenon of pruritus ? I'm interested in a general view about the subject, but detailed answers will be appreciated. ...
3
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1answer
76 views

What is the effect of reduced gravity on human height?

There has been talk recently of building a base on either the Moon or Mars. What I'm wondering is, if you are born and grow to adulthood on the Moon, where the gravity is a tenth of the Earth's, would ...
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1answer
52 views

What differences in effect does fast repetitive exercise have compared to slower muscle-building exercise?

As a drummer who likes to play high-energy music (fast, aggressive metal) it's safe to say I burn a fair amount of calories when doing so. But I've been drumming for over a decade and despite the ...
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0answers
47 views

Which Lactobacillales (Lactic acid bacteria — LAB) strains are capable of degrading starch?

I've been researching bacteria strains but am having trouble finding amylolytic LAB strains with amylolytic and lactic acid producing character. The only species I've found, that are capable of ...
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2answers
6k views

Can humans transdermally absorb minerals from ocean water, and if so how much?

According to several studies quoted here, chemicals can be absorbed by the skin transdermally, at least under certain conditions. When it comes to elements in seawater like sodium, magnesium, ...
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2answers
98 views

Why we have to damage our muscles to build them?

I know that new muscle cells are made when actin fibers are disrupted. My hypothesis is that muscle mass is limited, from birth, and that nutrients (protein) are only directed to grow muscle when ...
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0answers
33 views

Is lung size/shape a factor in long-continuous running of animals?

Apart from other factors, does lung shape/structure/size play any role in long-continuous running animals. Is there any similarity in lung structure between different long-continuous running species? ...
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2answers
7k views

Why there is a very high drop in pressure from arteries to arterioles?

Laplace law explains why the pressure is the same in aorta and arteries (100). I am thinking why there is so big drop in pressure when going from arteries to arterioles (40-60). Why there is a great ...
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1answer
123 views

Are there fishes with a double circulatory system?

Our courseware materials say there are such fishes, but my Internet searches suggests fishes only have a single circulatory system.
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70 views

which organelle produce glycogen phosphorylase and why

I know that Glycogen phosphorylase doesn't produce from rough endoplasmic reticulum in liver cell. But almost every proteins such as insulin receptor, serum albumin, and lysosomal enzyme have to ...
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0answers
57 views

What is a common body composition in mammals?

The Physiology Of The Racing Greyhound states that most species have about a 40% muscle mass to body mass ratio. Understanding Body Composition puts "optimal fitness" in humans at 16-25% body fat for ...
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2answers
270 views

What is the relationship between W, X, Y and P, M retinal ganglion cells?

In Guyton and Hall Textbook of Medical Physiology (12e) the retinal ganglion cells (RGCs) are classified into W, X, and Y types. However, in Gray's Anatomy (40th ed.), RGS are subdivided into midget ...
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1answer
81 views

Does exercise really reduce stress in the biological meaning?

It is a very widespread claim, that movement in general helps body to get out stress hormones. It is used as a warning for long sitting at the computer and I also heard it as a pro-vegan argument (We ...
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2answers
7k views

Why do we urinate more when we are nervous?

This question is a result of my personal experience... But I guess that is common for many of us. My school timing is 8:00 am to 1:30 pm (usually). During normal school days I typically urinate one ...
5
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1answer
131 views

Normal ECG/EKG Measurement?

I'm getting started using ECG using a 3 lead system by iWorx. I have place the leads on my two wrists and the ground on my ankle and have recorded some data into the provided LabScribe 3 software ...
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3answers
863 views

Where does extra blood come from to fill your muscles during exercise?

Let's say I go to the gym and lift some weights an hour. During this time my arms will grow due to the "pump" -- the extra blood rushing in to feed the muscles. For example, I've measured about 2-3 ...
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0answers
77 views

What is the essence of difference of how different chemicals affect the same receptor?

It is known that various chemicals can bind to the same receptor type, producing different effects. Be these chemicals agonists or antagonists, there are more variations in how they influence the ...
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0answers
161 views

Size of classical liver lobule across species

A classical liver lobule is made up of a central vein and the portal triads. A typical human liver weighs around 3 lbs. , while a typical bovine liver weighs around 12 lbs. I was wondering if anyone ...
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1answer
428 views

If a human is stranded with beer but no water, should they drink it? [duplicate]

TL;DR: At what percent (if any) will alcohol dehydrate you more/faster than drinking nothing? Let's contrive a situation for dramatic effect... A human goes out on a boat for a nice sail in the sea. ...
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0answers
78 views

Root etiology of non-pituitary low T4 and low TSH

Please note: I'd like to preface this question by stating that this is neither homework nor me seeking medical advice. I am simply trying to understand the biological, physiological root etiology ...
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2answers
6k views

What is the mechanism behind “acquired” alcohol tolerance?

I can understand natural variation in alcohol dehydrogenase (ADH) in a population leading to variation in rate of inebriation (after controlling for other variables -- e.g., mass, food consumption, ...
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3answers
586 views

What is the difference between meristem and bud?

Keep reading both terms quite frequently while studying plant physiology. I did some research trying to establish their differences and I learnt that meristems are undifferentiated cells that can ...
5
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1answer
165 views

Case study and speculations on the brain of Edward Mordake

I am very interested in the case of the man named Edward Mordake who lived in the 19th century. In particular, he had two faces. If you have not heard of this man, please, search this up as there are ...
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2answers
547 views

Should we induce fever to assist healing?

I am currently reading "The Fundamentals of Anatomy Physiology" 10th edition, and have found it an incredibly interesting book. I have just been reading about the lymphatic system, and the various ...
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1answer
168 views

Do people with congenital analgesia feel cold?

There are a few diseases that cause an insensitivity to pain. This question asks about the relationship between the cold and pain, which got me thinking: Is shivering a response driven by the ...
3
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1answer
794 views

Is the swimming pool water harmful to frogs who jump in? If so, how?

Here is an odd question: Frogs have permeable skin. Indeed, via capillary action, frogs absorb water through their skin. Chlorine is in principle a harmful substance. I am sure what percentage of ...
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1answer
58 views

does phagocytosis dependent on opsonization?

does phagocytotic activity of macrophages and neutrophils depends on opsonization by IGg (antibody) and C3 complex,if it does, so then why macrophages and neutrophils are categorized in Innate immune ...
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1answer
185 views

Drinking soda triggers tingling on a tiny spot on my upper back… but how? [closed]

The title pretty much says it all. Yes, I know it doesn't make sense. That's why I'm baffled. For the past week or two, I've noticed that drinking soda seems to cause a tingling/stinging sensation ...
10
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4answers
2k views

Do tall people have more cells?

Within a single species, how does the relative number of cells in the body relate to the relative size of the organism? Let's say we take two humans, one of them is 6 feet tall and the other one is 5 ...
6
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1answer
86 views

What is the top speed of muscle contraction?

Currently I am looking into what muscles groups are most used during a football kick. I have a hypothesis that the quadriceps are not as used as most people think because the momentum the swing ...
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1answer
4k views

What are the risks of elevating the legs too regularly and when tired?

I started to to think the pathophysiology of elevating legs high next to the wall too often and when you are tired. I think possible manifestations some damage to valves of the veins (No!) because ...