Questions tagged [human-physiology]
For questions on the biochemical, physical, and mechanical functioning of humans in good health including their organs and cells.
387
questions
0
votes
0
answers
28
views
Where does water go in glycolysis?
One of the products in glycolysis is water. The muscle consumes the energy, the waste products along with the water are carried through the bloodstream?
Independently, if the core body temperature is ...
- 11
-4
votes
0
answers
32
views
Are Reproductive Hormones produced in both males and females identical or are they slightly chemically distinct?
Are Oestrogen, Testosterone, Luteinizing Hormone, and Follicle Stimulating Hormone exactly identical in both males and females?
For example, I know both males and females produce Follicle Stimulating ...
- 1
0
votes
1
answer
80
views
Is “random arousal” in humans still caused by/connected to “background” sex drive?
I’m not sure if the title is the best way to word the concept but I don’t know how else to put it briefly; though honestly this question itself might be a bit hard for me to communicate concisely in ...
CommunityBot
- 1
0
votes
1
answer
293
views
Human Fat Adipose Tissue: Maximum Energy Transferred out per Day?
The article "A limit on the energy transfer rate from the human fat store in hypophagia" states that subjects with moderate activity levels are found to have a limit on maximum energy ...
-1
votes
0
answers
53
views
How is the human respiratory tract supplied with moisture?
The human respiratory tract contains a lot of moisture. The alveoli have to be kept moist for gas exchange to occur. The airways also have to be moist to moisten the air before it reaches the alveoli. ...
- 169
2
votes
1
answer
794
views
Why does exhaled air still contain oxygen?
If the partial pressure of oxygen in the atmosphere is 159 mmHg and that inside human alveoli is 104 mmHg, and if these values are fixed or don't change very much, then why does exhaled air have ...
- 2,351
1
vote
0
answers
29
views
Does Lymph Clot?
According to my professor, lymph has the ability to clot because it contains plasma which has dissolved fibrinogen. He says that as long fibrinogen is present in a bodily fluid, it should be able to ...
1
vote
0
answers
55
views
What happens to the gamma motor neuron during too much contraction of a muscle?
Suppose a muscle is contracting too much, so we need a reflex to stop it from contracting too much.
Contraction of a muscle causes the muscle spindle to go slack, hence the Ia axons and II-axons do ...
- 44k
0
votes
0
answers
32
views
Working in heat
What does working in temperatures of 180 degree dry heat for long periods do to the body?
Such as inside of a cooking cyclone scraping product out of it while it's still at 180 degrees.
10
votes
1
answer
18k
views
Upon drinking water for the first time in a long time, why do I sweat?
If I don't drink water for a long period of time (e.g. 10 hours), as during fasting, and then I break the fast by drinking water, I start sweating. Why is this?
0
votes
0
answers
15
views
What is the cost of increased neural adaption for strenght?
Axiom: Physical strength is a function of muscle mass and neural adaption.
I understand that increases in muscle mass incur associated metabolic costs. What are the corresponding costs for neural ...
- 101
1
vote
0
answers
70
views
What torque can the human wrist take?
Say you are holding a rod in one hand with your tumb on one side and the rest of your fingers on the other. What amount of torque could be exerted onto the rod (with the axis of rotation being around ...
0
votes
0
answers
45
views
Minimum conditions for human life
I don't know so much about biology, my strengths it is in physical science and mathematics.
Well i like rifle shooting, I don't hunt, i think that is cruelty and coward.
In some conditions of temp,...
- 1
1
vote
1
answer
348
views
How are testosterone levels distributed among men and women?
Wikipedia tells me that men have 7 to 8 time higher levels of testosterone than women, on average.
Since the hormone is linked with performance in certain athletic events, my hypothesis, which I ...
2
votes
1
answer
219
views
How does sperm gets oxygen in the female reproductive tract?
At the time of insemination, sperm along with seminal plasma enters in female reproductive tract and the plasma contains fructose for providing the energy to sperm
If the fructose follows just EMP ...
- 116
0
votes
1
answer
108
views
Can citrate in semen be utilized as a source of energy by the sperm?
Prostatic secretions of semen include citrate as one of the component.
The role of citrate in motility has been suggested by some researches.
(Kavanagh JP. Isocitric and citric acid in human prostatic ...
- 109
1
vote
0
answers
22
views
What is the mechanism behind antibiotic resistance and how can it be mitigated or prevented? [closed]
What causes antibiotic resistance, and how can we combat it? I am interested in the mechanisms behind antibiotic resistance and strategies to prevent it in bacteria.
- 11
0
votes
0
answers
20
views
Why does mild compression lead to paresthesia but not paralysis?
When a body part is compressed for a short period of time, why are only sensory neurons affected (paresthesia/anesthesia) by compression but not motor neurons (paralysis)? Like, the body part gets ...
- 101
0
votes
0
answers
44
views
CSF types in humans
There are several blood types such as A, B and O. Crossing these blood types such as in a transfusion, the results can be fatal. Along these lines, issues can arise when an organ or bone marrow are ...
- 44k
0
votes
0
answers
43
views
If the Z-line is pulled from both sides , how does it move to shorten the sarcomere?
When I was considering muscle contraction as a whole, this issue came to mind.
Which side should the Z-line of myofibrils shift to when it is being pulled by actin filaments on both sides to which it ...
- 3,277
2
votes
0
answers
23
views
What proportion of lung compliance is attributable to alveolar surface tension?
I am reading Guyton and Hall, chapter 38, Pulmonary Ventilation. It states that the two main factors influencing lung compliance are 1) tissue elasticity 2) surface tension elastic force. An ...
- 407
4
votes
2
answers
482
views
How deep underwater could you breathe using a tube which breaks the surface until the water pressure makes it impossible to inhale air?
I'm struggling with a question asking how deep you can breathe underwater using a hollow reed before the water pressure makes it impossible to inhale. The question asked to use this data of maximal ...
- 121
12
votes
3
answers
8k
views
How deep under water can humans open their naked eyes without damaging them?
Humans can tolerate a maximum pressure of 100atm, but it becomes uncomfortable above 30 atms. Deep divers usually wear protective equipment like goggles among other things and our eyes seem to be more ...
- 24.3k
0
votes
0
answers
24
views
What signals the corpus luteum to degenerate once the placenta is formed?
I've been trying to learn what causes the corpus luteum to finally degenerate once the placenta is ready to take over (in other words what is the trigger or signal and where is this signal produced) I'...
- 1
2
votes
2
answers
171
views
Do afterload and stroke volume form part of a negative feedback loop in blood pressure regulation?
Blood pressure is the product of cardiac output and total peripheral resistance:
$\text{BP} = \text{CO} \times \text{TPR}$
Since cardiac output is the product of heart rate and stroke volume, we have:
...
CommunityBot
- 1
0
votes
1
answer
425
views
Where would vegetarians/vegans get a substitute of hemo/myoglobin from?
As far as I understand, there is a difference in the iron absorbed from meat than from other sources like grains and vegetables.
If this is the case, is it possible that not ingesting the hemoglobin ...
- 1
0
votes
0
answers
38
views
Estimating Weight of Human Skeletal Muscle?
Is there a way to measure the weight of skeletal muscle? I understand body fat and lean body mass can be measured by: skin fold calipers, electrical impedance, table lookup based on formula of weight,...
- 215
2
votes
0
answers
153
views
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 ...
CommunityBot
- 1
4
votes
1
answer
690
views
Does food continue to stay sequential once it is inside my body?
I may be very off on many scientific details here, but I'm always all ears.
As far as I understand, any food that is eaten goes to the stomach, gets broken down even further into smaller food ...
CommunityBot
- 1
0
votes
0
answers
14
views
Human Body Muscle Mass: How to calculate new BMR?
Does anyone know how to calculate BMR that accounts for the total lean muscle mass? Specifically for someone that has been performing resistance training and their values may differ than norms?
I ...
- 215
9
votes
3
answers
1k
views
Why does eating saturated fat increase blood cholesterol?
I am interested in the biochemistry of diet and the way we have been advised to eat for the past forty years.
In researching an explanation for the relationship between dietary fat and blood ...
- 1
-2
votes
1
answer
248
views
What are the mechanical properties of human skeletal muscle?
TL;DR: I need more information on the mechanical properties of human skeletal muscle; if you have such information, please give it to me.
I'm writing something on how much more effective (or otherwise)...
- 44k
1
vote
0
answers
22
views
Why’s brush bordered columnar epithelium found in intestine and not brush bordered cuboidal when I’ve been explained that they have the same function?
I searched for differences between their functions which would result in their positioning but none of it satisfied the answer to my above question.
- 11
2
votes
0
answers
45
views
Has electrical activation, rather than mechanical tension been investigated as a direct trigger for hypertrophy?
Three of the most common theories for what induces hypertrophy are mechanical tension, muscle damage and metabolic fatigue.
The prevailing theory at the moment is that mechanical tension is the main ...
- 579
0
votes
3
answers
286
views
How does 2,3 biphosphoglycerate works to release oxygen bound to the hemoglobin?
I read on Wikipedia that 2,3 BPG binds with the deoxygenated state of hemoglobin and helps in stabilizing it. It was also written that it helps release remaining oxygen from the hemoglobin. How?
...
3
votes
1
answer
60
views
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 ...
- 142
0
votes
0
answers
164
views
How can children scream so loud and so long?
Recently I saw a small baby shrieking extremely loudly (my ears hurt) for at least 4 minutes .
How is it possible? If I yelled so loudly, I would be defeated by throat ache after less than a minute. I ...
- 295
0
votes
0
answers
39
views
Is it better for a person's stomach to have 1 big meal or 2 small meals? Does this change as a person gets older?
Is it better for a person's stomach to have 1 big meal or 2 small meals? Does this change as a person gets older.
Also what about water? Is it the same way or different and why?
0
votes
0
answers
25
views
Why does oogenesis have to begin in foetal stage itself?
In males, spermatogenesis begins after puberty and they retain this ability throughout their life time. However, in females, oogenesis begins and ends in the foetal stage itself and the female is ...
1
vote
1
answer
159
views
How is it possible to breathe perfluorocarbon?
I have heard of liquid breathing, where an organism, usually a person, would be breathing in perfluorocarbon. Now I looked up perfluorocarbon on Wikipedia and I noticed, no oxygen at all, but fluorine ...
CommunityBot
- 1
14
votes
4
answers
45k
views
Will the heart keep beating if it's separated from the body?
The heart is a vital organ in our body, as it drives blood circulation. I was wondering if a heart keeps beating if it is separated from the body? If yes, then why?
- 52.3k
1
vote
1
answer
208
views
Entry of particulate pollutants into the nasal cavity
NCERT Chemistry of Grade XII (India) writes
Particulate pollutants bigger than 5 microns are likely to lodge into the nasal passage, whereas particles about 10 microns enter the lungs easily.
I'm ...
- 10.3k
1
vote
3
answers
97
views
How can you diagnose albinism in a naturally light-colored person? [closed]
Not all albinos have white hair. There is a type of albinism where the affected person has light yellow hair and the skin color can be the same as a normal North European person.
How can you diagnose ...
- 2,455
4
votes
1
answer
119
views
How long does it take for a new muscle fiber to be connected to motor neuron?
When new muscle fibers are formed through hypertrophy, how long does it take for motor neurons to connect to the new muscle cells in order to be able to control them?
After taking a break from ...
CommunityBot
- 1
6
votes
1
answer
253
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 ...
- 44k
4
votes
0
answers
131
views
Which single substance among Potassium and Phosphate has the greatest osmotic activity in the Intracellular fluid?
My physiology textbook mentions that potassium has the greatest concentration ( 155 mEq/L ) in the Intracellular fluid and that I thought would make it the most osmotically active but the answer given ...
- 41
4
votes
2
answers
2k
views
Why do humans lose subcutaneous fat tissue with age?
Why exactly do humans lose subcutaneous fat tissue with age?
It appears that we either lose fat cell volume or we might actually be losing the number of fat cells with age.
One hypothesis is that as ...
2
votes
1
answer
210
views
Is Pars intermedia functional in humans?
My textbook says, "Pars intermedia secretes only one hormone called melanocyte stimulating hormone (MSH)."
My teacher says that in humans MSH is secreted by the anterior lobe because the ...
5
votes
2
answers
11k
views
Wim Hof Method claims Alkaline Blood is Good. Contradictions? Counterproof?
The Wim Hof Method claims, that it is beneficial to have alkaline blood.
On the other site there is the medical claim that if the pH-value is not within the
range of 7.36 – 7.42, enzyms are ...
1
vote
0
answers
29
views
Phenotype of a possible gene mutation
I have noticed multiple cases where patients had similar body characteristics :
decreased ability to gain weight (slim)
they are capable of sleep only 6 hours or less with normal functioning (...
- 320