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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4
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1answer
30 views

How do I know which alleles the parents have?

I have the following assignment where I am to look at the "tree" (not sure the english word) and assign whether or not they can be autosomal dominant or recessive as well whether they can be X-linked ...
3
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0answers
16 views

How pronounced is the difference if we would change the running direction for runners?

I was jogging when I asked myself this question: In running contests the standard running direction is counterclockwise; I also believe to remember that the regulation is very old (right back to the ...
-4
votes
1answer
58 views

How does visual sexual arousal work between the eyes, brain, and genitals/gonads?

When many people look at sexual images, they often can become sexually aroused, including full genital arousal, and feel urges, known more often used as "horny" as slang/urban usage. How does this ...
1
vote
1answer
43 views

Does homeopathic or herbal treatment of cancer have any scientific recognition?

Even though we have a very high tech society, cancer is still a serious issue. We humans still are not entirely capable of fighting cancer. Radiation and chemotherapy are still considered the best ...
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0answers
44 views

Why my right eye see warmer colors? [on hold]

As the title says, my right eye see warmer color than the left one. I've seen a few people talking about that thanks to google, but I was unable to find a proper answer. So, what cause this strange ...
4
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0answers
20 views

Is it possible that the vapour form of propylene glycol could lower a humans blood oxygen saturation by the manner in which N2O does?

My understanding is that by inhaling nitrous oxide leads to the body not being able to take in as much oxygen as it usually would. Is it possible that a heavier soluble gas such as the vapour form of ...
4
votes
0answers
35 views

Does anxiety about weight or eating cause people to become overweight?

A while ago I saw this TED talk about the futility of dieting. The speaker suggests that a body maintains a homeostatic weight point and returns to that weight after dieting has stopped: Turns out ...
2
votes
0answers
46 views

Can DNA test of my grandparent's brother reveal my heritage from that branch of the family?

I'm thinking about doing that DNA test on all my grandparents to know where their genes come from. They are getting very old and I don't want to let the opportunity pass to gather more knowledge about ...
2
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1answer
36 views

Explanation of ECG in MI using an electrostatic model

I found a paper presenting an electrostatic model to explain the ECG recorded in various leads. This model essentially calls for considering the depolarization wavefront to be the major contributing ...
0
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1answer
22 views

How is cancer associated with host pathogen interaction?

Does cancer by any chance fall under host pathogen interaction domain? What I mean to ask is that, is there pathogen interaction involved in cancer? I went through this article: ...
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0answers
11 views

Phytoestrogens from hops in beer and estrogenic activity in humans

There is a saying that phytoestrogens from hops can cause male boobs in male beer drinkers. Are there any reliable studies linking beer consumption to increased estrogenic activity? In males and ...
0
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1answer
25 views

What is meant by clonal isolates?

With respect to this website: http://horfdb.dfci.harvard.edu/ what does the term clonal isolates mean?
0
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1answer
49 views

Would somebody born 'reversed' (e.g. heart on their right side, etc.) be completely healthy?

By reversed I mean their body is a complete mirror image of a normal human's.
6
votes
1answer
70 views

Why is the brain dependent on glucose?

The strict dependence of the (human) brain on glucose has always been puzzling to me. While ketones can substitute for a portion of the brain's energy needs, it cannot substitute completely: blood ...
0
votes
1answer
42 views

Why do teeth decay of sugar?

Sugars is a common component in diet of mammals. Why then their teeth did not develop resistence to sugar decay?
0
votes
3answers
82 views

How does frame-shift mutation not absolutely ruin the organism?

I'm a bit curious as to how frame-shift mutation works. If you shift one amino acid towards another. How does this not affect the entire chromosome? Wouldn't this mean that the organism would be ...
0
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0answers
14 views

Over what range do Thyroid Stimulating Hormone (TSH) levels tend to fluctuate over the course of a day?

I understand that the majority of doctors consider the TSH test "the gold standard" for measuring thyroid function (examples stating that literally are here and here). The reference range for what is ...
-1
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0answers
22 views

Regarding benzoic acid and its effects

One of the users on the chemistry s.e. mentioned that when benzoic acid forms in the body in response to other chemicals it might have a mutating effect on one's DNA. Is this true?
1
vote
1answer
19 views

What causes muscle spasms?

What causes muscle spasms with muscles that are not in the heart ? Could it be some sort of stimulus overload that causes a massive contraction?
1
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1answer
20 views

Human population growth - where can I find the data?

Out of curiosity, I'd like play around with data of human global demography. Where can I find data that describe the "per region (per continent for example) population size" versus time since the ...
0
votes
1answer
29 views

How does cancer of the larynx (laryngeal cancer) affect the respiratory system?

The larynx is part of the respiratory system and is responsible for producing sound (our voices). My question is how cancer in the larynx (voice box) affect the respiratory system overall? I ...
1
vote
1answer
37 views

Feeling of spicy

I have done a survey on my friend When everytime they eat something spicy, They will eat ice or drink icy water. First, Mostly they feel nothing but a cool sensation. However when they finished, they ...
2
votes
1answer
44 views

What happens when we stretch?

From the wikipedia page on stretching: Stretching is a form of physical exercise in which a specific muscle or tendon (or muscle group) is deliberately flexed or stretched in order to improve the ...
3
votes
1answer
50 views

Bayes theorem for mutations

MEN 2A is a dominant inherited disease caused by a mutation in the RET proto-oncogene. The probability of being sick when you have the mutation of the RET proto-oncogene varies with age and is assumed ...
4
votes
1answer
35 views

How can a heart of human work if one of its valve is not working?

Yesterday I went to a hospital and heard a doctor say that one of the heart valves of a patient is not working. However, the patient was still alive and was healthy; the patient could walk and talk ...
2
votes
1answer
95 views

Is homosexuality an adaptation in humans?

Homo sapiens have menopause - as some other mammals (e.g. some Cetacea) - a phenomenon where older females live for decades after the end of their own reproduction. Perhaps homosexuality, that looks ...
0
votes
2answers
39 views

Why is my peripheral vision better for seeing in the dark? [duplicate]

I often walk around my house at night with the lights turned off and one night I noticed that looking straight at an object with very little light available made the object disappear from sight but if ...
4
votes
1answer
83 views

Do human-ape hybrids exist?

Since humans and apes share up to 99% of their DNA, can they interbreed? For example, a horse and a donkey seem to be just as distantly related and produce offspring. Mules, however, are sterile. ...
3
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0answers
48 views

Is there any biological support for the concept of “chakras”? [closed]

Is there any support in modern biology for the ancient concept of "Chakras"? I've seen the concept of 7 chakras linked to the major endocrine glands in the human body (pineal,thyroid, adrenal, ...
-1
votes
1answer
86 views

Does the DNA of a tadpole change after it becomes a frog?

Does the DNA of a tadpole change after it becomes a frog? In other words what changes take place as a tadpole becomes a frog, and does this metamorphosis affect the DNA in any way? I would appreciate ...
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0answers
42 views

How many mitotic divisions do haploid cells undergo before fertilization?

Background This question is about human physiology and gametogenesis. A spermatozoid is not necessarily the direct "offspring" of diploid cell. Stated differently, a spermatozoid cell can be the ...
-2
votes
1answer
79 views

Our muscles give us the ability to move our arms but…? [closed]

I have a strange question, but let me tell you something first. If you think of this carefully, then you realize something, please try this right now: Contract your muscles only so that your arms ...
1
vote
1answer
19 views

Difference between pulse and blood pressure

I'm a very naive and biologically illiterate person, and from what I've read on the internet I'm not really sure I understand the difference between pulse and ...
-6
votes
1answer
58 views

Why do fingers swell during cold winters?

When exercising, tissue in the hands may swell. This may be caused by the muscles generating heat, which leads to blood being pushed to the vessels closest to the surface of your body to dissipate the ...
3
votes
1answer
60 views

Human bone density and Brown Bear bone density?

It is stated on this website that the density of a Grizzly bear bone is ten times our own. And since I am not into biology at all, I am confused as I don't understand the meaning of bone density here. ...
2
votes
1answer
38 views

Help reading gene markers

I'm sorry if "gene markers" is not the correct word. An edit could be appreciated but I don't study in an English speaking country unfortunately. Question overview: In a family, there is a genetic, ...
2
votes
2answers
31 views

Help reading chromatogram

A genetic variation is found in this chromatogram: It says that the "reference sequence" is the top line and that I can use the general genetic code to find the reading frame. I can see that there ...
5
votes
1answer
66 views

Why do we get tired

At the end of a day full of work, it is general for people that their eyelids start to feel heavy. Laziness takes over and we begin to yawn. We all know that we're tired at that time, but why people ...
5
votes
1answer
59 views

What's a mouth ulcer/canker sore “made of”, and why do they develop?

Mouth ulcers are red/white rings with a crater. They are sore and last for 7-10 days. What I want to know is what they are 'made of' - i.e., what is the ring filled with, and why is the centre crater ...
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0answers
26 views

The ring formation of ringworm

I know ringworm is caused by a fungus on the skin, nails or scalp but what causes the rash to form as a ring instead of like a normal spread out rash?
4
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0answers
22 views

Do blood glucose “spikes” contribute to insulin resistance, or is prolonged elevation required?

There's increasing public discussion about the health risks of chronic insulin resistance* (IR). In many cases there's a focus on high glycemic index foods that "spike" your blood sugar, which implies ...
0
votes
1answer
97 views

Why should or shouldn't we allow the human body to take its natural course? [closed]

For example, when you are sick but don't feel thirsty, this could be due to baroreceptor reflex that is attempting to readjust salt and water balancing. Why shouldn't a patient be left thirsty and ...
7
votes
1answer
359 views

Why do people feel pleasure when using roller coasters / centrifuges?

The feeling when using an amusement park unit is usually a pleasure. Why is it not a pain instead? Are there advantages, from an evolutionary point of view, in loving this potentially dangerous ...
3
votes
1answer
106 views

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

Why is there the need to map these everyday words into another set of words, it seems to complicate matters. Is it done mostly out of tradition or is there some logical basis to it?
0
votes
1answer
40 views

Survival with only water but no food [duplicate]

How long can the average, healthy adult human survive with only water?
1
vote
2answers
46 views

Can leukopenia in a person with an otherwise normal immune system lead to non-infectious diseases in the long-term?

If a person has developed leukopenia as a side-effect of long-term use of anti-convulsant medications and his/her immune system appears normal otherwise (does not get infections any more often than a ...
4
votes
1answer
39 views

How can human infants express chymosin with only a pseudogene at their disposal?

I read on the Wikipedia article about Chymosin http://en.m.wikipedia.org/wiki/Chymosin It stated that chymosin is produced by gastric chief cell in human infants. But it also stated that human only ...
0
votes
1answer
18 views

Beta oxidation of saturated fats

In my text book there is an example of a 18 carbon long fat and it says that it can run 8 laps of oxidation. I don't understand why it doesn't run 9? 2 are removed each cycle? Thanks.
1
vote
1answer
39 views

Why use creatine phosphate?

We use creatine phosphate as an energy storage to resupply ADP with a phosphate group as our muscle cells only contain about 2-5 mM ATP. But why doesn't the muscle cells just keep 20-30 mM ATP instead ...
0
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0answers
30 views

Why doesn't the body optimize how many fatty acids it burns?

Ketone bodies are produced due to an excess of fatty acids being burned (accumulation of acetyl-CoA) so my question is: Why doesn't the body simply regulate how many fats it burns so it doesn't have ...