This tag is for questions about the general anatomical features of human beings as opposed to the anatomy of non-human animals.

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5
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1answer
42 views

Does the anatomy of our hand result in (computer) mouse-accuracy that varies by direction of movement?

First off, I apologize if this isn't the right stackexchange sub-site for asking thsi question. I was torn as to where I should post this question: it could plausibly belong in Biology, User ...
-2
votes
0answers
56 views

Why does human hair grow over our eyes [duplicate]

As many people who are overdue for a haircut will know healthy human hair will eventually grow to cover your eyes. I wonder- why is this so? In the modern world it is not a problem. We have invented ...
6
votes
2answers
101 views

Which part of human body sustains most pressure when standing up straight?

Let's suppose a healthy fit barefoot young adult standing comfortably on a flat solid surface. A reasonable guess is somewhere around the foot. But is it the ankle, the heel, or the Metatarsus?
8
votes
3answers
164 views

Why are the organs for reproduction and urinary excretion combined?

We eat food for getting energy to our body parts, and we excrete the wastes through urine, feces, and perspiration. Why has nature combined the urinary tract with the genital system (urogenital ...
2
votes
1answer
46 views

Is the golden ratio of anatomic measurements universally beneficial for sexual reproduction? [closed]

It is often claimed, in popular media, that the golden ratio (Fibonacci series) in for example some face measurements is aesthetically (and hence reproductively) attractive with respect to the humans. ...
3
votes
1answer
61 views

Do humans have skin cells that trigger oxytocin release in the brain?

I was reading an article by Montgomery on the therapeutic effect of pets (Boston Globe, January 12, 2015), and I found this quote: All animals appear to have cells directly under the skin that ...
2
votes
1answer
21 views

How many smaller muscles compose the interosseus muscle in the human hand?

When looking at Wikipedia, I read that the interosseus muscle is actually composed of 3 muscles, but on the French Wikipedia, they talk about a 4th muscle. So how many interosseus muscle components ...
3
votes
1answer
34 views

Why is it difficult to bend the waist while keeping the knees straight?

It's easy to keep your legs straight when you're standing up or laying flat on your back, but as soon as you try to sit up or bend down, you need to bend your knees as well as your waist. (Try it. ...
2
votes
1answer
37 views

What is the distance between the sciatic nerve and the colon at the closest point?

Is it possible that a full colon impinges on the sciatic nerve? Is there anything that physically separates the sciatic nerve from the colon?
2
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0answers
21 views

Hypoglossal nerve location

I kind of know where the hypoglossal nerve is located when I look at the diagram but I'd like to know how far is the nerve from the skin and where is the closest area to the skin before and right ...
1
vote
1answer
61 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.
0
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1answer
30 views

Does the term “upper extremity” include hands?

I see on http://en.wikipedia.org/wiki/Upper_limb that the term "upper extremity" seem to include hands. However, in many hospitals, there is a "Hand & Upper Extremity Service", which would tend to ...
3
votes
1answer
23 views

Does the palate truly house the sense of taste?

Source: Your “palate” is the roof of your mouth, and by extension, your sense of taste. I was reading Etymonline's entry for palatable {adj.}, which cites and derives from palate {noun}: ... ...
0
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0answers
57 views

Does ale give less of a hangover than a lager?

I got into an argument surrounding beer type and hangover. Apparently there is a opinion that ales give you less hangover than lagers do (considering same alcohol content consumed). My understanding ...
1
vote
0answers
81 views

How can I see that the human hand has 27 degrees of freedom?

I have counted the degrees of freedom in my hand over and over and I keep getting the number 19. Suppose each finger has 3 degrees of freedom. Then 5 * 3 = 15. The wrist can rotate around or back and ...
4
votes
1answer
75 views

How pain can stimulate the vagus nerve

I'm trying to find out why a prompt, severe, short pain is causing a stimulation of the vagus nerve. What could the physiological explanation be? Is that because the pain is triggering the ...
8
votes
4answers
887 views

Is there any way a human could whistle and be unable to speak?

Is there any situation anatomically, where a human could understand the speech of others perfectly, without any capabilities of speech themselves, but would retain the ability to whistle with a tune? ...
2
votes
1answer
197 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.
5
votes
2answers
228 views

Can someone who cannot talk still whistle?

Can someone who has a damaged larynx, which does not allow them to talk, still create a tune when they whistle? I know that the larynx is what allows a person to manipulate their pitch and volume, ...
5
votes
1answer
41 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 ...
6
votes
2answers
383 views

Why is the opposite of plantar flexion called “dorsiflexion”?

Why is the action of flexing the foot so that the toes move anteriorly/superiorly (i.e. in the direction opposite that which they move during plantar flexion) described as "dorsiflexion"? In the same ...
3
votes
1answer
82 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?
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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 ...
0
votes
1answer
52 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 ...
5
votes
2answers
77 views

Why are there no artificial wombs yet?

If the conditions within the womb are mimicked, and proper amniotic fluid with constantly recycling nutrients is maintained, is it not possible to obtain an artificial womb? Is there anything missing? ...
7
votes
1answer
114 views

What creates the feeling of 'excess' blood pressure to an area of the body?

If I hang upside down, and feel blood rushing to my head, what structures are actually responsible for me "feeling" this excess flow of blood? Baroreceptors? Mechanoreceptors? Something else? ...
4
votes
1answer
108 views

How does aging affect fingerprint?

Do fingerprints change as we grow from child to adult? Most notably, what is the effect of the increase in surface area of palms and fingers on the finger print? Does the finger print simply increases ...
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
votes
1answer
118 views

What happens to our umbilical cord internally as we age?

I was always curious as to if or how much of the internal structure or workings of the umbilical cord are still in existence as we age. What happens to it over time? The wikipedia article naval ...
6
votes
1answer
98 views

Do people that don't feel pain shiver in the 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 ...
12
votes
1answer
203 views

Average dimensions of the human back (anthropometry)

I am wondering if anyone can point me to (a scientific source that provides) the estimates of the dimensions (length x width) of the human back? I am specifically interested in the dimensions ...
0
votes
1answer
2k views

why male penis not considered as cartilage? [closed]

Penis don't have bone like ears & nose, then why why male penis not considered as cartilage? en.wikipedia.org/wiki/Cartilage
2
votes
1answer
42 views

Can an upper forearm amputee correctly control the Median and Ulnar nerves

I'm an engineer who is looking to build a robotic hand for people without their upper forearm(from center of forearm in direction of hand), controlled by the Thalmic Myo(an EMG sensor). I am first ...
1
vote
1answer
131 views

How do you call that part of the muscle that connects directly to the bone?

When you open up a chicken leg or a clam and you remove the meat, there is this little part that is connected to the bone and is not easily scraped off. What is this part called and what mechanism ...
0
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1answer
34 views

Does the size or mass of a body affect the time it takes for rigor mortis to sets in?

Does the size or mass of a body affect the time it takes for rigor mortis to sets in? For example: compare a 300 pound man to 100 pound girl to 5 pound animal.
3
votes
2answers
84 views

Is it possible to move your arms above your head when handcuffed in the back?

This move was seen in Pitch Black and i wonder if it is possible at all. Say you are handcuffed to a pole, hands in the back, and the pôle is a little higher than your head. You just want to do a ...
0
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0answers
52 views

Why do we have butt hair? [duplicate]

Why do we have hair on our butts? From what I understand, hair is generally used for warmth, but it seems like our buttox would be one of the last places on our body that would need warmth. Moreover, ...
4
votes
1answer
79 views

Miscarriage in early humans

Today, about 10 to 20 percent of known pregnancy end in miscarriage. Pregnancy is a biological process that has been very well studied by medicine. As a result, modern medicine helps a lot to prevent ...
-3
votes
1answer
289 views

Are transgenders born physically different from others?

Are all children born with only either male or female body parts (other than exceptions), or is there actually a natural third gender with the physical characteristics of both genders, e.g. the child ...
3
votes
1answer
283 views

Names of nerves in hands, shins and face

I am looking for the names of the nerves in 3 specific locations of the human body: The nerve running along the "top" (opposite side of the palm) portion of the thumb, from knuckle to fingernail ...
0
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0answers
278 views

Physiologically, how can stress/anxiety cause neuropathy?

According to the Mayo Clinic, stress/anxiety can cause "pins and needles" (neuropathy) sensations all over the body. But how can this be? My understanding of the sensory pathway is that sensory ...
1
vote
1answer
81 views

Can signals travel “backwards” in the sensory pathway?

My understanding of the "sensory pathway" is that its a linear, directional pipeline as follows: Nerves (fire various signals depending on the type of sensors they are) Fibers (transmit signals from ...
2
votes
1answer
61 views

Anatomy of nervous system's sensory pathways

When I touch my hand on a hot stove, I feel pain. I'm interested in knowing all the main "endpoints" (components/parts of the body) that are involved in relaying this pain signal. As I understand it ...
1
vote
1answer
51 views

How and where do nerves share pathways to the brain?

I am interested in understanding how pain receptors send signals to the somatosensory cortex (the part of the brain that registers various nerve signals such as pain, presure, temperatures, etc). ...
1
vote
1answer
67 views

What specific sensory nerves act as receptors for “pins and needles” (neuropathy)?

According to this excellent answer, the difference between "pain" and "pins and needles" (neuropathy) is that different receptors (sensory nerves) trigger in reaction to different stimuli. Different ...
3
votes
2answers
327 views

Why do we have to exhale (or inhale) in order to speak?

Every time we speak, sing, or make any other kind of advanced noise with our throats, we exhale, or to put it that way, blow air through our throats. Why is this required? After all, speakers do not ...
8
votes
1answer
549 views

Do the right-handed people tend to use the right side teeth of their jaw to chew food more often than the left-handed people?

And vice versa, do the left-handed people tend to use the left side teeth of their jaw to chew food more often than the right-handed people?Or the frequency of food chewing distribute fairly to both ...
3
votes
1answer
89 views

Why do we have two of some organs, but not all?

We have two eyes, but we don't have two hearts. Why do humans have two of some organs, but not all?
2
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1answer
131 views

Why can't people talk while inhaling?

Why do we have to exhale in order to talk? From looking on Wikipedia, it seems like it has something to do with the glottis, but I'm not clear on the mechanism that makes speech sound so different ...
3
votes
2answers
356 views

Why do humans have only two nipples?

If other animals have more than 2 nipples, then why do humans have only 2 nipples? Even my pet dog has more than 2 nipples.