Questions tagged [human-anatomy]
This tag is for questions about the general anatomical features of human beings as opposed to the anatomy of non-human animals.
536
questions
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How do tapeworms aid weightloss?
The 5 second answer people come up with is, "well they consume calories you otherwise would have". This logic works great if we're discussing the impact of my brother consuming part of my ...
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0answers
17 views
Is there any meaningful ratio between the width of a vertebra and its height and depth?
Given the location (i.e. their entry points, but not their trajectories) of two pedicle screws, we are trying to come up with a way to approximate the sagittal distance of the vertebral foramen to the ...
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61 views
Is there a functional reason why the right side of the heart has a tricuspid valve while the left has a bicuspid one?
Is there a functional reason why the right side of the heart has a tricuspid valve while the left has a bicuspid one? Why is it necessary that the right atrioventricular valve be 3-cusped?
2
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1answer
142 views
What is inside digestive system while it's empty?
Up to this point, all my life I assumed that stomach and intestines are filled with air. I got this impression from all the anatomic drawings in schoolbooks and encyclopedias that show empty stomach ...
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0answers
24 views
Which of dB or dBA are more useful for predicting damage to hearing?
With no information about noise other than its loudness measured in decibels or in A-weighted decibels, which can be used to more accurately predict how much hearing damage may be caused?
Even though ...
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0answers
64 views
Can the effect of an allele on height be context-dependent?
Some data is available on the effect alleles have on height. For example Common DNA Variants Accurately Rank an Individual of Extreme Height
However after browsing the literature I was not able to ...
0
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1answer
120 views
What is the proper anatomical name of the "band of Richer" that wraps around the quadriceps femoris?
There's this fascial band called the band of Richer that wraps around the quadriceps femoris muscle above the knee (in this illustration, look for it near the left knee). It seems to stem from the ...
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1answer
114 views
What is the difference between the cheeks and the near parts?
Linguistically, there should be the different property or feature between cheeks and the parts right near them for us to call cheeks “cheeks.” What is the main difference between cheeks and the other ...
1
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1answer
59 views
Is human skull size related to brain size?
Me and my dad have a disagreement about this. He thinks that if a person had a larger skull they would naturally have a larger brain. I think that he is assuming the evolutionary trend holds on an ...
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0answers
23 views
Are there any congenital anomalies that cause a lack of epicanthic folds in a child who would normally have them?
Wikipedia lists several medical conditions associated with epicanthic folds. Mount Sinai says that epicanthic folds in a baby who would not be expected to have them is a diagnostic tool that indicates ...
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0answers
14 views
In what layers of skin are free nerve endings found?
I found online that free nerve endings are found in the epidermis and dermis, but I couldn't find information on what specific layers of the epidermis these free nerve endings are found in like the ...
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1answer
63 views
Why can't I swallow the entire (liquid) contents of my mouth at once?
I've tested this out using water - I manage to fit a certain amount of water in my mouth, but if I try to gulp it all at once, I fail: I feel like spitting the water out (gag reflex?) There's a ...
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0answers
33 views
The location of pulmonary valve in comparison with the aortic valve
According to most transverse diagrams of heart, the pulmonary valve, in comparison to the aortic valve, angles towards the left side a little bit. Take, for instance, the pulmonary valve is more ...
1
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1answer
72 views
Is it possible to see some renal pyramids in a transverse section those which cannot possibly be viewed in one longitudinal section at the same time?
This is just a random image I found on Google.
It is showing that, in cross-section, several renal pyramids can be viewed. Is it so?
According to the following longitudinal section of the kidney, I ...
0
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0answers
29 views
What is seperating one muscle from another in body?
I have been learning about gross anatomy and have been watching a lot of dissection videos online and this question has me a bit confused. I know that the human body have about 600 muscles. I know the ...
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0answers
17 views
Cell location co-ordinates [closed]
I have just had the nails on both my big toes removed. I am much happier. But it got me to thinking, as there is no 'root structure' from which the nail grows, is there an x,y,z, type co-ordinate ...
38
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2answers
5k views
Why do we have two kidneys but one liver?
Both the liver and the kidneys are involved in "cleaning" our blood. But why we have one liver and two kidneys? I can just as well imagine that we have two livers and one kidney. Is this ...
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39 views
Does Vasa deferens produce any secretion in the Human Body?
I got this doubt while attempting the following question:
...
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0answers
25 views
Motion of Fallopian tube fimbriae
The fimbriae at the ovary end of Fallopian tubes are described as "sweeping" eggs from ovaries into the tubes:
When ovulation is about to occur, the sex hormones activate the fimbriae, ...
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0answers
40 views
Why does bicep activate during dead hang?
Hanging from a bar causes my bicep to feel much harder than when simply holding my arm straight above my head relaxed, without a bar.
This was slightly surprising to me: I used to assume that since ...
1
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0answers
36 views
Brain centers vs areas (and how they relate to nuclei)
I'm looking for a reputable source that can provide succinct definitions differentiating the following terms in the central nervous system (CNS; particularly in the brain):
Area
Center
Nucleus
...
2
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0answers
57 views
What determines walking direction in humans?
I've wondered about this for a while, without being able to come up with an answer.
Is there a body part that single-handedly determines the direction we're walking in? Is it a group of body parts ...
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1answer
52 views
Can a person survive without platlets in the bloodstream? [closed]
Can a person survive without platlets or thrombocytes in the bloodstream, if I guarentee that the person is isolated and won't injure?
Any help will be appreciated. Thank you!
0
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1answer
161 views
What type of epithelium are the pancreatic Islets of Langerhans?
The human pancreas contains exocrine acinus cells (simple cuboidal epithelium) and Islets of Langerhans. Despite looking online I cannot identify what type of epithelium the Islets of Langerhans ...
0
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3answers
94 views
Why aren't the twin organs like both the eyes, ears, hands and legs lying both sides of a human body identical?
Both the eyes are not identical in geometrical shape and size i.e. physical appearances of both the eyes of a person are different from each other. The same difference is observable in both the hands, ...
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0answers
30 views
Are the foramina of Magendie and Luschka genuine defects of the ependymal epithelium?
Question:
Are the foramen Magendie (or the median aperture) and the two foramina Luschka (or the lateral apertures) genuine defects of the ependymal epithelium? So the ventricular lumen truly ...
0
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1answer
105 views
Evolutionary selection pressure for human hair patterns?
Are there hypotheses or conjectures that postulate any selection pressures or benefits that account for the patterns of non-pubic human hair? Particularly:
Humans do not grow notable (i.e., non-...
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2answers
32 views
In human anatomy / biomechanics, what is the motion called when the arm swings sideways so the elbow moves in an arc of 90 degrees?
In human anatomy / biomechanics, what is the motion called when the arm swings sideways so the elbow moves in an arc of 90 degrees?
So e.g. if a person was to elbow somebody behind them , or if ...
2
votes
0answers
20 views
The exact points of muscle attachment and the "equal and opposite force" that skeletal muscles apply
I've been trying to make a simple simulation of the human body executing some motions in Mathematica (the details are irrelevant), but I need to know some more information about muscles and how they ...
1
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0answers
10 views
Flexor/extensor group in lower arm and limb bud rotation
Have the flexor and extensor groups in the lower arm have rotated laterally 90° towards the humerus epicondyles independently of the rest of the lower arm? The pre-axial and post-axial veins are still ...
1
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0answers
35 views
What is the thinnest spot on the ilium called?
Is there a specific name for the spot on the human iliac fossa where the bone is the thinnest? (Or, is there a name for the thickness measurement of that spot, e.g. the left/right _________ is 2.1mm?)
...
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0answers
35 views
The position of the macula in comparison to the blind spot
Which is located in a higher postion? Macula or blind spot?
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1answer
70 views
Animal species anatomy [closed]
https://en.wikipedia.org/wiki/Animal
Do all animal species have two lungs and two kidneys similar to human beings?
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1answer
133 views
Can a hinge joint technically allow rotatory motion?
Let's use a hinge joint and pivot joint as examples.
When talking about the difference between them in terms of movements permitted, I see that on any websites and textbooks, the term 'rotation' is ...
0
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0answers
90 views
Is there any ethnicity difference in average pupil size?
I have seen some articles claim African Americans have smaller average pupils than whites while Asians have larger pupils. Is it true?
link:
Y. Li, D. Huang; Pupil Size and Iris Thickness Difference ...
14
votes
1answer
152 views
Do patella bones form in people born with the inability to walk?
The patella is a sesamoid bone that typically doesn't completely from and ossify until ~3-6 years of age (e.g., Source). My long-standing understanding (supported by a claim in Saladin's college A&...
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0answers
41 views
Is the diaphragm made of two muscles?
Is there a 'crural' and 'costal' parts of the diaphragm as suggested in this paper or is it just a single muscle?
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0answers
24 views
How do Human Skin Creases Vary?
I am studying human gross anatomy in order to produce an anatomically correct CGI model of the human body. As part of this, I'm attempting to understand the different features that define the ...
1
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1answer
44 views
Why proprioceptive fibres (of CN V) have their cell bodies in mesencephalic trigeminal nucleus?
It's seen that GSA (General Somatic Afferent) fibres (of CN V) have their cell bodies in trigeminal ganglion. But the proprioceptive fibres' peripheral processes terminate at mesencephalic trigeminal ...
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1answer
34 views
Pectoralis muscles as push muscles vs pull muscles
Pectoralis muscles are the adductors, flexors of arm in addition to medial rotators of arm. How does this action translate in to acting as helping in push ups or in bench press?
I am having trouble ...
2
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0answers
53 views
Clarification for the anatomical terminology of the cerebellum
I've been trying to find descriptions for some of the fissures found on the inferior surface of the cerebellum, and so far the only source I've been able to find that provides an adequate description ...
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0answers
47 views
Phantom Limb | Is that even possible?
I am fascinated by the fact that an amputee can control their robotic arm by thinking of the actions they would normally execute when the limb was present.
The mind sends signals to the nerve endings ...
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0answers
15 views
Can the eye determine which type of defocus is presented to it?
I have a question regarding myopic and hyperopic defocus.
My question is, is the eye able to determine which type of defocus is presented to it and if so what mechanisms allow it to distinguish ...
16
votes
1answer
3k views
Why are the pulmonary vein and artery not like the rest of circulatory system?
I'm learning anatomy. What I learnt is that we have arteries that have oxygenated blood which appears red in color, and branch blood to arterioles to deliver blood to cells via capillaries from where ...
2
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1answer
130 views
is there a limit to how much humans can taste?
kind of a weird question, sorry, but i was wondering--is there a threshold at which our taste buds become overwhelmed? if i, say, put some supersweet compound in my mouth, would there be a point at ...
2
votes
1answer
394 views
Can the human eye axial length decrease?
I just have a quick question regarding the axial length of the eyeball.
I understand that the axial length of the eyeball grows up until your around 20 years of age which is why hypermetropia ...
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2answers
123 views
What's the difference between the terms "muscle" and "muscle organ"?
Foundational Model of Anatomy distinguishes between Muscle organ and Muscle. What's the difference between the two?
0
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1answer
81 views
Can the shoulder bones grow after the growth plates have fused?
Body builders have broad shoulders. If one start lifting weights after one's growth plates have fused, can one still increase the width of one's shoulders? If yes, does that mean shoulder bones can ...
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2answers
75 views
If black absorbs light, then why did Africans evolve black skin? Wouldn't that make the heat worse? [duplicate]
Wouldn't it have been more adaptive to develop light skin and so reflect incoming light?
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0answers
43 views
Profile of a human foot
I am not sure if this is the right place to ask this question, so please let me know in case it is not. My question is just out of curiosity.
What is the reason for curved human foot profile?
First ...
