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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3
votes
1answer
132 views

Is there a difference between drinking water straight from the tap compared to leaving it to sit?

An idle question - if a glass if filled from the tap and consumed immediately, it contains some dissolved oxygen from the physical process of moving through the pipes & tap. If left out ...
2
votes
1answer
35 views

Are all tastes just a combination of sour, sweet, bitter, etc.?

For example, can the taste of pineapple be isolated to just a certain amount of "salty-taste-triggering-molecules" and "sweet-taste-triggering-molecules" etc.? Can our current understanding of the ...
5
votes
1answer
6k views

Do human anal glands have any function?

Anal glands in all kinds of animals play a range of diverse functions - providing fat for preening feathers or waterproofing fur, generating distinct scent, even repelling predators. None of the ...
7
votes
4answers
1k views

Why do obese people tire quickly?

Fat people have a large amount of calories (energy) stored, but I have noticed all time when they do physical activities they get tired fast in comparison to fit people - why does this happen?
14
votes
1answer
11k views

What is the female equivalent of the morning erection that some men experience?

There was question about what causes "morning wood." It was answered that the erection in the morning is caused by decline of norepinephrine during REM sleep. Which in part allows to prevent ...
6
votes
1answer
333 views

How to identify the age of a “living” person?

An Indian old man claims he is 180 years old now. 180 years old We are not able to tell he is 180 or 181 probably. But can we tell he is 90, 120, 100 or 150? Different people may age differently. ...
6
votes
2answers
110 views

What are possible health risks to women having large numbers of children?

What is the possible health issue the women would face in this record? The record for most children born to a single couple belongs to the first wife of Feodor Vassilyev of Russia. In 27 ...
6
votes
1answer
170 views

Can androgen-insensitive genetic-males get pregnant?

According to the linked report, people with androgen insensitivity syndrome appear as male, but have both feminine and masculine outer genitalia. However, I was not able to find out whether their ...
17
votes
2answers
2k views

Can Biologists identify all viruses?

I went to the doctor today with my girlfriend, and the doctor said that she had a virus but doesn't know which one and she should let the infection heal with some rest. The fact that the doctor ...
3
votes
2answers
81 views

Do humans contract more physical sicknesses and diseases than animals do? [duplicate]

I wondered: If I get into the library and look into the medical section it is evident that there are thousands and thousands of different human physical diseases. But if I look into the section of ...
3
votes
1answer
61 views

Why does a Urinary Tract Infection cause a strong, persistent urge to urinate?

There are plenty of articles on the fact the a urinary tract infection (UTI) causes frequent and urgent urination. For example; on this National Institutes of Health webpage. My question is: Why ...
0
votes
1answer
126 views

Cancer in myogenic heart cells? [duplicate]

Why cancer does not occur in myogenic heart cells? Is there any special ability in heart cells to resist cancer ?
1
vote
1answer
36 views

Breathing becomes harder in certain wind conditions

I'm not sure if this is the right site to ask this, but it seemed like the best option. I've observed on myself that, if I stand on a train platform and a cargo train drives by, creating strong, ...
-2
votes
1answer
188 views

How may the age of a child be estimated when required to do so, in video-graphic evidence?

How may it be possible to roughly conclude that a subject in a select piece of video-graphic evidence presented, is in fact a child, i.e. without the subject being, physically examined? Is it ...
2
votes
1answer
64 views

Reseach on feeling pain of other people

I'm more of a tech than bio kind of guy, but I have read and learned a lot alongside of my girlfriend's education. Which is very interesting!! Currently I want to investigate : people claiming to ...
4
votes
1answer
440 views

What kinds of cells does human saliva contain?

I have heard that our saliva contains cells. What cell types can be found in human saliva?
4
votes
1answer
98 views

Why do you retch when you see something disgusting?

Why do you retch when you see something disgusting? I imagine it is some sort of evolutionary response, although I can't see the connection between receiving a signal that unhealthy conditions are in ...
14
votes
1answer
49k views

Why do vaccines cause your arm to hurt?

When you get a shot for a vaccine (for example, the annual flu vaccine), the nurse frequently indicates that your arm will ache for a day or two, maybe more. This ache is typically not just a pain ...
3
votes
2answers
117 views

Do intestinal flora have the same DNA as their host?

Please bear with me, this is not my professional field and I might be mixing things up. In an explanation why seeds won't start growing in one's intestines, the explanation given was that foreign ...
3
votes
2answers
122 views

Can an argument be made that humans are 90% bacterial?

On the blog, All about Scientist in Microword: Microbiology, I read the post We are 90% bacteria, actually, which says that humans are 90% bacterial cells. If this is the case, then why don't we ...
2
votes
1answer
28 views

ATP to disassembly of nucleotide ratio

DNA Helicase, the enzyme that is responsible for tearing apart the strands before DNA replication, requires ATP to rip apart nucleotides. I have asked this question to several professors and they ...
4
votes
0answers
28 views

Can we predict a person's tolerance to cold exposure during excercise?

Being an amateur athlete and student of anatomy I've always wanted to know if there is a formula for determining an unconditioned body's tolerance to cold temperatures while exercising. I know the ...
4
votes
2answers
113 views

Can Hepatitis be caused by Bacteria?

There are many information about viral hepatitis. But it is interesting for me, can bacteria cause the hepatitis too?
0
votes
1answer
46 views

How body loses more fat in CO2 form than in sweating form? [closed]

Yesterday, I saw TV Game Show. There is question like this: Body loses more fat in which form? It gave 4 options: 1) CO2 2) sweating 3) xxx 4) xyz sorry i didn't remember 3 & 4 options. ...
7
votes
1answer
798 views

What is the effect of garlic on intestinal flora?

Now that we can compare whole microbiomes, has there been investigations on the effect of garlic (or diallyl disulfide, its main ingredient) on intestinal flora? From the proven antimicrobial ...
9
votes
2answers
403 views

Where do the bacteria within the vagina originate from?

I understand that it's feasible the bacteria within the gastrointestinal tract originate from the food we eat and air we breath, but where does this population of microbes originate from?
14
votes
2answers
209 views

Relationship between our microbiome and personalized nutrition

Recently, it has been asked whether there are 'metabolic types' between humans that can benefit from a sort of personalized nutrition. One answer suggested that one discerning factor could be the ...
2
votes
1answer
39 views

How many diseases can be linked to disruption in the microbiome of a human?

I was listing to the radio and heard recent research found a link between children and higher cases of asthma when certain bacteria are missing from the microbiome. How many other diseases can be ...
1
vote
2answers
208 views

What is the function of E-coli bacteria in our stomach?

So, I recently came up with this question. I googled it, but couldn't understand the proper functions of E-coli bacteria. A little definition would be wonderful.
6
votes
1answer
403 views

Why does a fetus drinks and urinates into the amniotic fluid?

I was reading this website saying that fetuses urinate into the amniotic fluid. It also mentioned that, because we drink the amniotic fluid, we’ve been drinking our urine for months. However, why do ...
11
votes
3answers
4k views

What is the evolutionary reason behind the fragility of teeth?

Almost all organs in the human body have a rather large threshold within which the organ or tissue is capable of repairing itself using materials supplied by the body, whether it's made from organic ...
5
votes
1answer
80 views

Colorblindness in females and random X chromosome inactivation

From Annenberg Learner: Because the X is inactivated randomly in cells, one cell could have the maternal X inactivated, while the adjacent cell could have the paternal X inactivated. This causes ...
3
votes
1answer
138 views

Are there human-ingestible liquids that do not contain water?

My son asked me a question that stumped me: Is there anything a human can drink that does not contain water? It stemmed from a conversation in beverages in general where I was pointing out that they ...
0
votes
1answer
47 views

When does lactation occur?

High levels of estrogens and progesterone antagonize prolactin’s effect on the mammary glands, and it’s only after the placenta has been removed and the levels of estrogens and progesterone has ...
1
vote
1answer
60 views

Do vitamins protect you from common cold? [closed]

Do vitamins (taken as pills) boost your immune system, and make you less likely to contract diseases such as common cold or flu?
7
votes
1answer
5k views

What are the advantages and disadvantages of being ambidextrous?

Most of us have one dominant hand. We find it nigh on impossible to do very delicate or dextrous activities with our other-hand. This seems like an apparent weakness, and a rather odd one when you ...
6
votes
2answers
279 views

Why can't our eyes smoothly transition from side to side without focusing on a moving object?

Why are we not able to slowly and smoothly look from side to side, or up and down in a single and smooth transition, given that we are able to do this if our eyes are focused on a moving object?
3
votes
1answer
194 views

Why do humans masturbate? [closed]

Why does masturbating seem to be like an addiction? What controls or initiates the urge to masturbate? Is it good or bad or both and why is it so? I have heard guys who say that the do it ...
6
votes
1answer
648 views

Why is there no cure for Dandruff?

It looks like a simple problem, affecting almost half of the population at the post-pubertal age and of any gender and ethnicity [wikipedia]. What is so complex about finding a cure? Also, if you know ...
1
vote
0answers
39 views

Which sperm fertilizes the egg?

Hundreds of acrosomes must undergo exocytosis to digest holes in the zona pellucida. This is one case that does not bear out the adage, “The early bird catches the worm.” A sperm that comes along ...
1
vote
1answer
7k views

Is diabetes mellitus a sex-linked disease?

There are two types of diabetes mellitus. a. Type 1 diabetes mellitus b. Type 2 diabetes melliuts Is either of them a sex linked disease? Can either one be inherited? My book says, "this disease is ...
2
votes
1answer
74 views

How does the pancreatic beta-cell know how much insulin to secrete in response to glucose?

How do $\ce\beta$-cells know how much glucose is in the blood? I know that when glucose enters a beta cell it triggers the cell to produce insulin. $\ce\beta$-cells trap glucose by converting it into ...
8
votes
1answer
139 views

What is the main challenge in creating a chemical male contraceptive?

More than 50 years after hormonal contraception for women was invented, a contraceptive pill for males is still not available. With the obvious major biological differences in mind, why does it appear ...
0
votes
0answers
27 views

Why exactly does a scarf help against a neck pain and a sore throat?

I was going out without a scarf and as this day my neck was more sensitive; after a while my voice was rasping, I needed to cough and my neck was hurting slightly. After coming home I put on my silk ...
-5
votes
1answer
107 views

Why are plants classified in living things? [closed]

@Volunteers Beware that I am none of the biological magnates. Nor a philosopher. This is just a sign of curiosity. And, I want only an intuition that enables me to see the difference. As far as I ...
11
votes
1answer
120 views

Why do doctors still advise HIV+ couples to wear a condom during sex?

HIV infected people already have HIV, but why do doctors still advise condom use for HIV+ couples?
4
votes
2answers
390 views

Can people with AIDS get tattoos?

When I do a Google search, most of the results are about whether or not people can get HIV / AIDS from getting a tattoo through dirt needles. I am, however, curious whether or not it is possible to ...
0
votes
2answers
166 views

Is it possible to stop yourself from going into shock?

https://en.wikipedia.org/wiki/Shock_(circulatory) I was helping someone move a refrigerator down steps and it slipped while I was holding a sharp corner and it sliced my finger and there was ...
0
votes
1answer
32 views

How DNA programs the first cell in womb into a human [closed]

Sorry if you see me silly. I am just a programmer happens to be curious about biology... So far I understand how DNA make protein, how cell divides, how one composed of cells->tissues-> organs. ...
0
votes
0answers
22 views

Pathogenesis of type IV hypersensitivity

In hypersensitivity, as I understand it, a normal immune response gets excessive, misdirected or wrongly regulated to cause tissue injury. The various types determine the various ways in which the ...