This tag is for questions about the general biological features of human beings (as opposed to the biology of non-humans).

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2answers
51 views

Difficulties understanding a pathway [on hold]

I am not a biologist and I would love to understand what is going on with this pathway. I went to the description but it's still complicated, and I couldn't follow. Can someone please help me with it? ...
1
vote
1answer
17 views

Pasteurization and Bioavailability of Antioxidants in Beet Juice

What are the effects of pasteurization on the antioxidants found in beet juice ? Does the process render most of the beneficial nutrients (betaine) useless and make them unable for the body to process ...
2
votes
1answer
55 views

What is the impact of stress on the human body?

Can stress trigger any changes in the human body? I'd like to know more about things less commonly known than, for example: sweating and tiredness. What are the long term risks of chronic stress? Do ...
3
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0answers
41 views

Is it possible for a human to wake up in a wrong way?

There's an old folk saying that goes like "He got out of bed on a wrong foot" - to indicate that the person's day is going poorly because of the way that person woke up. Is it is possible for a human ...
0
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1answer
26 views

What would happen if we had a device that produced oxygen inside of our lungs? [closed]

Hypothetically speaking, suppose there is a device that produces a limitless supply of oxygen. The device is inhaled by a human and is resting inside the (a) lung. What would hypothetically happen if ...
8
votes
2answers
108 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 ...
1
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2answers
56 views

How does the body respond to blood donation; are there any possible risks?

Can blood donation cause any harm to the donor? I have been told so, but cannot find any references supporting this claim. I have also learned that our body will replace the lost fluids within 24 ...
2
votes
1answer
102 views

Possible genotypes for blood types?

If I am blood type B, what are all the possible genotypes that could be expressed by my parents? I think it might be 16 but I was reading online and saw this: Similarly, someone who is blood type ...
0
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0answers
40 views

Why can't we remember something sometimes? [closed]

We've all had something a time where we "learned" something for school and then forgot it the next day. However, we remember something that happened 3 years ago. Why is our short term memory ...
0
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0answers
33 views

What are possible physiological causes for dry, irritated facial skin when failing to shave? [closed]

I am aware that skin can become dry and irritated AFTER shaving, but what could be a reason for the same result when letting facial hair grow out? It makes sense why shaving would cause the skin to ...
2
votes
1answer
141 views

When contracting a muscle will the muscle spindle stretch or contract?

When you contract your muscle, will your muscle spindle stretch or contract? And why? I was always under the impression that it was contracting your muscle spindle, but now I am not sure.
6
votes
2answers
98 views

Are unilaterally deaf people able to determine where sound comes from?

My question is on people deafened in one ear, but normal hearing in the other. Time and level differences between the two ears are only part of how the human body can localize the source of the ...
6
votes
2answers
52 views

What level of cellular radiation is harmful for humans?

What level of radiation at the frequencies used by the cellular network(1-2 Ghz) is harmful for human health?
5
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1answer
35 views

Stretching and compressing bones

The Young's modulus of elasticity when a bone is stretched is : 16×109 and when it is compressed, it is 9×109 N/m2. That means, change in length will be more if you compress a bone as compared to ...
4
votes
1answer
37 views

By what mechanism does Risperidone swell breast tissue?

There has been much talk of the anti-psychotic drug Rispeirdone causing un-natural breast tissue growth as well as galactorhea (milk production). Especially in young men and boys. What is the ...
2
votes
1answer
32 views

What causes the line patterns in the palm of the hand?

The line patterns on the hand are unique to each individual, but what causes these lines and re they advantageous in anyway?
2
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0answers
19 views

Atelectesis due to decresed surfactant in lungs

Surfactant is a protein lipid mixture produced by alveolar pneumocytes composed of Dipalmitoyl Phosphatidly Choline lipid,apoproteins and calcium ions. This surface lines the alveolar epithelium ...
1
vote
1answer
21 views

What are the roles of cadherins in epithelial mesenchymal transitions? [closed]

I know that cadherins control the expression of cancer cells involved in the epithelial-mesenchymal transitions, but I was wondering exactly how the process worked.
4
votes
1answer
205 views

What do trans-fats do when in human body?

Trans fats cause health problems, especially to the heart. https://en.wikipedia.org/wiki/Trans_fat#Health_risks My guess is that all effects happen because trans-fats are inherently toxic as the ...
4
votes
1answer
268 views

What is our skin made up of?

Again, it is a basic question. What is our skin made up of? is it made up of many cells arranged in a systematic way or is it just like any layer say of a book?? what is the difference? where is the ...
4
votes
0answers
57 views

How to tell if a beverage will hydrate or dehydrate?

Beverages of any type generally contain some measure of water. However, in the case of some liquids, the non-water components take more water from the human body to filter out than the water contained ...
2
votes
1answer
44 views

Why do haemophillic females $X^hX^h$ die before birth?

I just came across a statement in my book , while reading genetics, that haemophiliac females do not survive till birth (the reason not mentioned here why) . Before posting this question here I ...
1
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0answers
26 views

how food moves in horizontal coils of small intestines [duplicate]

This is a very very basic question, and I am looking at it more from point of view of physics. The small intestine is a highly coiled structure, which means it has horizontal coils as well. I can ...
7
votes
1answer
250 views

Are bacteria necessary for an individual's life, or, how long could a person live without bacteria? [closed]

Bacteria are essential to life in that they are responsible for breakdown of organic substances, etc. but are bacteria necessary for an individual's life? In other words, how long would a human ...
2
votes
1answer
43 views

The human organism knows what we have to eat? [closed]

My mother has told that if your organism needs a vitamin, you want fruits include that vitamin. For example you have lack of C-vitamin you would like to eat lemon. Is there any explanation for it, or ...
0
votes
0answers
35 views

With humans, is being transgender innate, or caused by social factors?

In humans, is being transgender something that is innate, or is it caused (or made more likely) by social factors such as their political beliefs, their religious views or their social environment?
1
vote
1answer
35 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 ...
0
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0answers
13 views

Does the use of a Thiazide diuretic affect the ability of a hair follicle to absorb substances?

Thiazide diuretics are on the World Anti Doping Agency's, as well as the International Olympic Committee, list of banned substances due to it ability to mask illegal substances in urine. The rapid ...
1
vote
2answers
49 views

What percentage of human body's cells are contained in blood?

What percentage of human body's cells are contained in blood vs. the rest of the body?
1
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2answers
28 views

Can ingesting substances that are produced by the body cause a permanent withering of the organs that produce the substance?

This question is about substances such as insulin and some vitamins that the human body is able to produce on its own. Some substances that are produced by the body are also present in various body ...
0
votes
1answer
28 views

How does the Pectoralis Major work when doing a bench press?

Disclaimer, I'm not a biology undergrad and I only know the basics about muscle movement. I know that doing a bench press works the chest, and specifically the Pectoralis Major because, well, I feel ...
1
vote
3answers
88 views

Does the necessary Carbon Dioxide need to be in the atmosphere for mammals?

In the answers to this question, we've learnt that carbon dioxide is necessary for mammalian life, but is it necessary in the atmosphere/to breathe it in? Or does the act of respiration give a ...
2
votes
1answer
44 views

Genetic abscence of backpain among teen girls? [closed]

I heard a study somewhere (I can't remember where) that claimed that teenage girls are genetically absent to experience high degrees of backpain, specifically from rigorous exercise. Strangely, of ...
12
votes
3answers
3k views

Superhuman eyesight

My ten year old son was reading car number plates that were too fast, too far away and at the wrong angle for any of us to read or even believe that it was possible for him to read. We thought he was ...
2
votes
0answers
34 views

Is it possible that weak memory is due to interference between signals in the brain?

"Weak memory", as used in this question, refers to the inability to retrieve a memory that a person otherwise knows he has memorized earlier. An example of this is some fact snippet that the ...
10
votes
2answers
146 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
votes
0answers
50 views

Time lapse between fresh blood's exposure to air and that same blood turning darker red-brown

For investigative purposes, I'm searching for a tool that can be used as a quick visual assessment of the the length of time that blood has been exposed to air after the blood flow has stopped.. Let's ...
3
votes
0answers
193 views

Why are fingerprints different even in identical twins? [duplicate]

Why are fingerprints different from person to person? It can't be genetics. Even identical twins has different sets of fingerprints. What is the deciding factor that form and shape our fingerprints?
2
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0answers
26 views

Neural correlates of the function of the cardiovascular system?

Are there any known neural correlates of the function of the cardiovascular system? I'm looking for research results that use standard brain imaging techniques (e.g. electroencephalography, ...
2
votes
1answer
57 views

Biphasic T wave caused by digitalis toxicity

Digitalis is a drug that can be used during coronary insufficiency to increase the strength of cardiac muscle contraction. But when overdosages of digitalis are given, depolarization duration ...
4
votes
1answer
85 views

What actually are thoughts? [closed]

The human brain consists of neurons that transmit impulses like wires that conduct electricity.I am confused about where are our thoughts stored and what really are thoughts? For example if I think ...
3
votes
0answers
36 views

Can we artificially increase human growth using HGH?

Robert Pershing Wadlow was a man who lived in the early-mid 1900s and had hyperplasia of his pituitary gland, which caused him over-produce human growth hormone (HGH) and grow to nearly 9 feet ...
8
votes
1answer
133 views

Why aren't green eyes more prevalent?

Why aren't green eyes more prevalent, given that the green allele is dominant over the blue one? My understanding is that human eye colour is determined by two genes: 1) HERC2, with alleles Bx, BB ...
4
votes
2answers
64 views

What is overdiagnosis?

What is overdiagnosis ? I have searched this Wiki result but didn't understood at all. Can you please explain the first two line of Wikipedia : Overdiagnosis is the diagnosis of "disease" that ...
1
vote
0answers
54 views

How does estrogen influence collagen synthesis?

Through what mechanisms does estrogen interact with collagen synthesis? Especially in the context of elevated estrogen levels and genesis of purpura simplex .
2
votes
1answer
40 views

Why does uterus have to be prepared every month for fertilization?

I'm just curious why it has to happen every month when the uterus could have been prepared from the beginning and kept that way throughout life or till a certain point. But why make and break it every ...
3
votes
1answer
178 views

Name (and meaning of the absence) of the white semicircle at the base of the fingernail?

At the base of fingernail, there is a white semicircle (see on the first picture). But sometimes there isn't one. My questions are: what is this white semicircle on the fingernail, and what causes ...
-3
votes
1answer
53 views

Human Species of Males/Females [closed]

Why is it that when there is discussion about Race/Subspecies it is never about the genetic/physical differences between males and females. So every argument has been about physical and geographic ...
8
votes
1answer
85 views

What senses are active while sleeping?

During sleep, our body activity decreases. I am wondering on the extent of the lowering of this activity regarding our five senses. Clearly, the sense of touch is still very efficient since shaking a ...
5
votes
1answer
138 views

Why do we get 'bags under our eyes'?

Why do these circles form around the eyes if somebody is tired? And why does fatigue express itself around the eyes this way? Can I get eye bags very quickly in another way? ...