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

learn more… | top users | synonyms

3
votes
2answers
6k views

What could cause hairs to gray at the tips but not the roots?

I have noticed that some of my sporadic gray hairs are gray at the tip side but oddly, not near the roots. Some are even only gray in the middle. I find all of this very counter intuitive, and I ...
3
votes
1answer
202 views

what are the mechanics of sweating?

The causes of sweating aside, i.e. I'm not interested in which and how nerve signals are transmitted to sweat glands. But I would like to read a detailed account on what a sweat gland consists of, ...
3
votes
2answers
97 views

Could humans theoretically see infrared better than regular light?

I have noticed that in infrared film, people's eyes reflect that light within their eyes much like nocturnal animals (and many other animals for that matter) do with regular light. I know that this is ...
3
votes
3answers
1k views

Why does the apex of the human heart usually point to the left?

In the majority of human beings, the apex of the heart (left ventricle) points towards the left side of the body. Sometimes however (approx. 1/12000 births), a person is born with a condition known ...
3
votes
1answer
98 views

Cucumber on the eyes

In many spas and salons I have seen people place a cold cucumber on their eyes. I think this might be for coolness, but why a cucumber? And Is it actually for coolness or for something else (like ...
3
votes
0answers
57 views

How do duplicate brain regions (ex: left/right amygdaloid body) operate together?

I frequently hear talk about parts of the brain like "Amygdala" or "Hypothalamus", so I looked them up in an app called "essential anatomy". What I see is that there's mirror symmetry, and most of ...
2
votes
2answers
516 views

What happens if a person has the right side of the body totally removed (including the brain)? [closed]

I guess humans could live without just the right lobe of the liver or the right brain. Could a person without the whole right side of body survive? The left brain controls the right side of the ...
2
votes
2answers
1k views

Why does the sweat of children not smell like adults?

My kids sweat plenty in this hot heat, but they don't smell afterward. I on the other hand need all kinds of deodorant. Why doesn't kid sweat smell?
2
votes
1answer
119 views

Difference between flexion and contraction?

i asked this to my anatomy teacher and he said there is no difference but when it comes to specialy in body building when you say to flex their bicep they freeze their upper limb in order to do that ...
2
votes
1answer
90 views

What is the evolutionary cause for various finger lengths?

Why are the lengths the way they are with middle finger the longest?
2
votes
3answers
168 views

Mechanical cause of loss of consciousness

Consciousness is an electrical and chemical interaction in the brain, caused by neurons firing and chemical interactions. How does a mechanical "force" cause this to stop working? i.e. How does a ...
2
votes
1answer
2k views

Which blood vessel carries the most impure blood?

There is a question in my Biology textbook: "Which blood vessel in the human body carries most impure blood after few hours of meal." The answer is given as Renal artery. But I think the ...
2
votes
1answer
54 views

Biology Analogy

In my book are given several paired analogies with me being asked to give reason for them. I could solve all of them except this: liver = thrifty house-keeper I mean, I do not understand why the ...
2
votes
1answer
96 views

Scrotal temperature and vascularization

The testes (at least in human males) are vascular organs, the vascularization extending even o the interstitial spaces of the seminiferous tubules. The function of the scrotal sac, is to isolate the ...
2
votes
1answer
54 views

How do cells figure out the big-picture shape?

I'm wondering what makes cells to divide (and stop) in such a way that they make our hands the shape that our hands are...
2
votes
1answer
487 views

Circulation through the liver in light of drug metabolism

I have a lingering question which stems from an answer that I gave to What hydrolyses aspirin within the digestive tract and blood stream? When a drug or any other substance is absorbed into the ...
2
votes
1answer
520 views

Function of the Auricle in heart

What is the function of the auricles (conical appendages through the atria) present in the heart? Do they have any other function than increasing the volume of blood the heart can hold?
2
votes
1answer
71 views

Development of vitreous humor

I have tried reading about development of vitreous humor but it is all very confusing. When does it first developed ? Does it renew itself ? Please provide reliable sources..
2
votes
1answer
134 views

Do people of the same height walk at the same speed?

I'm working on a project that concerns movement and the human body. Before I begin to experiment, I need an answer to a question I'm sure has an answer, but doesn't Google well. What I need to know ...
2
votes
1answer
102 views

Why do genitals feel frozen when freefalling?

I don't want to add much more about that. Since childhood I noticed a chilling effect, even when doing rollercoaster-type activities.
2
votes
1answer
156 views

Why do I breathe out of BOTH nostrils?

After reading the question why do I only breathe out of one nostril I realized that breathing out of both isn't common. I have always breathed out of both, and when I get a stuffy nose, or a runny ...
2
votes
1answer
147 views

Are Asian people shorter than Europeans?

People in different countries have different average heights. For example, Wikipedia's article on human height states that Australian men have an average height of 177.8 cm, and Australian women 163.8 ...
2
votes
1answer
29 views

Does digit 1 have an extensor sheath?

Extensor digitorum and extensor digiti minimi both insert into the extensor hoods of digits 2-5 (or just 5 in the case of e. digiti minimi). In every source that I can find, extensor pollicis longus ...
2
votes
1answer
33 views

What are the criteria for determining the origin and end of muscle anatomically?

For example the pectoralis muscle starts from sternum region and ends on the acromion or coracoid process. Why you can't say that it starts acromion process and ends on the sternum?
2
votes
1answer
69 views

Average face shape

I am doing face detection application where every face detected is inside a rectangle. The rectangle always contains some background behind the face and now I need to extract as much of the face as ...
2
votes
1answer
119 views

Why don't we have more cone cells (bigger fovea)?

Background Apart from being able to sense color, cone cells are able to perceive finer detail and more rapid changes in images, because their response times to stimuli are faster than those of rods. ...
2
votes
1answer
2k views

What negative effects can pinhole glasses have on the body?

While shopping in the local supermarket yesterday, I was surprised to find this display on one of the shelves. I also realize that I should have taken a pamphlet with me, as well as a picture of ...
2
votes
0answers
45 views

What causes headaches (biologically)? What does it mean directly? [closed]

Even though your brain can't feel pain, thingies in your head are installed to compensate for that. Once I thought your head starts to hurt when your brain is tired. I can't believe this any more. ...
2
votes
0answers
29 views

Questions regarding Scapulohumeral Rhythm

I'm actually an artist, but I wanted to ask this because it will help a lot in my figure drawings. My artistic anatomy teacher taught me about the Scapulohumeral Rhythm. He said that in during the ...
2
votes
0answers
102 views

Human female chest model or data representation?

I am looking for professionally used representation of female chest (I know how it sounds ;). Generally - a model comprehensive enough to effectively represent human chest, with focus on breasts. ...
2
votes
0answers
373 views

What is a lip? (upper lip and lower lip)

Everyone knows what a lip is but I'm asking from a technical and anatomical standpoint. Actually what we call "lip" is "vermilion" in medical terminology. But I want to ask if my understanding is ...
2
votes
0answers
39 views

How much does a human brain's metabolic rate vary? [duplicate]

Possible Duplicate: How does brain energy consumption depend on mental activity? Our brains consume about 20% of our energy when we're at rest. How variable is a human brain's energy ...
1
vote
3answers
165 views

What does orbital mean in orbital frontal cortex?

Orbital frontal cortex is where decisions are made. What does the word orbital there mean? I looked around in wikipedia and never find it.
1
vote
1answer
2k views

How are the paranasal sinuses linked with the capillaries in the ear canals?

Sinus congestion often seems to be accompanied by excess pressure on the outer ears (as anyone who has shared a transcontinental flight with an infant can attest to) or fluid buildup in the canals. ...
1
vote
1answer
55 views

Is the human collarbone supposed to break?

I've read it in a book and have heard people mention it, but I can't find any documentation about it. But the point being made is this: The human collarbone acts as a shock absorber for impact on ...
1
vote
1answer
12k views

I'm 20. Can I still grow taller? [closed]

I'm 20, in about 6 months I turn 21. For some time I've been wondering whether there are natural, non-surgical and non-pharmaceutical ways that humans can continue to grow after reaching adulthood. ...
1
vote
1answer
130 views

Why do we suffer abdominal pain after we get very angry or stress?

You also realize probably, when we get so much anger or high levels of stress, after some point we have terrible stomach ache, like really heavy pain. Why is that? How stress or anger can effect our ...
1
vote
1answer
56 views

Why are new vessels more permeable in microvasculature?

I know for microvasculature New microvasculature (arterioles, venules) are always more permeable as they lack pericytes. and then I have this sentence about new blood vessels (not specific) ...
1
vote
1answer
105 views

Breathing in and out

I was reading my textbook and it says that breathing involves inhaling and exhaling but it doesn't say whether they happen simultaneously or sequentially. Also is my overall understanding of ...
1
vote
1answer
58 views

Does a woman's G-spot actually exist? [closed]

Does a woman's G-spot actually exist? Are there any research studies? Links: G-spot (Gräfenberg spot) at Wikipedia U.S. gynaecologist says he has found the G-spot
1
vote
1answer
404 views

If penis reconstruction from a clitoris is possible why isn't penis enlargement possible?

I don't understand why, if a penis can be reconstructed from a clitoris for sex change, surgical penis enlargement is not possible.
1
vote
1answer
41 views

Anatomy suffixes?

Here are some suffixes I want to know their meaning: -ium: trapezium (carpal bone) -ius: trapezius (column muscle) -ous: Talous and calcanous (tarsal bone) -alis: Acromialis, Ulnaris (shoulder ...
1
vote
1answer
22 views

Specifics of decussation

Beginner question here: The definition of decussation I see is the crossing through the midline of a bunch of neurons. But I was wondering if there was a little more to it than this, because I'm ...
1
vote
1answer
51 views

People say the cardiac cycle depends on blood pressure? How so?

I know what the cardiac cycle is. There are two phases diastole and systole. One is the relaxed, and the other is the contracted form of the heart. The diastole is where blood is pumped to the ...
1
vote
2answers
92 views

What does ophthalmologist see in your eye?

I always wondered what ophthalmologists see inside someone's eye and what they're looking for. The whole thing is a mystery to me. Are there any photos of what the eye of a patient looks like from the ...
1
vote
1answer
432 views

Why does shaving dehydrate the skin? Is there an hormonal effect involved?

I want to understand why the face becomes dry after shaving and if shaving affects hormones? I've heard that after shaving, hair grows back faster, why? Shaving damages hair follicles and they become ...
1
vote
1answer
60 views

In a human, what non-germline cells have the highest/lowest mass?

I'm just curious which cells are largest/smallest in the human body other than sperm/ova.
1
vote
1answer
105 views

Why has our nose evolved with the nostrils facing down?

For most animals, the whole bottom of their face sticks out and they have a snout with a mouth and nose at the end. But humans have a flat face and just a nose that sticks out. We used to have the ...
1
vote
1answer
31 views

Are bronchioles and alveoli covered by respiratory epithelium?

Which parts of respiratory apparatus are covered by respiratory epithelium and which are covered by other kinds of epithelium?
1
vote
1answer
237 views

Near point and far point of myopic eye

Suppose a person wears the specs of power -6D, the far point for that person is 16cm. But the near point of normal eye is 25cm. So, is the near point of a person with myopia (having far point less ...