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.
494
questions
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1answer
34 views
Question about the anatomy of the human eye [closed]
Is there any part in the human eye that is responsible for keeping light out, or are all the parts of the eye involved in absorbing the light and allowing it in.
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20 views
What causes your 2 eyes to move in sync?
When you look left to right or up to down, youre 2 eyes move in perfect harmony. What nerve/system causes this coordination? I.e. could you tell me more about this system?
Thanks
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1answer
67 views
Why is the thyroid gland in the neck?
The neck seems like an odd place for it. All other neck anatomy must interface between the head and abdomen (trachea, esophagus, circulation, spine etc).
Surprisingly I have not been able to find ...
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0answers
29 views
Origins of the body mechanics theory
In physical therapy and occasionally in sports coaching, there's often a precise description of the mechanics of what happens during the movement (which muscles are engaged, which joint moves where ...
0
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1answer
47 views
Is the backward positioning of photoreceptors bad design?
(Several questions have been asked about this topic but most are quite old and there has been at least one study since then that has attempted to answer this in a new way)
Since photoreceptors are ...
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1answer
76 views
Genes associated with human female breast size
What are the genes associated with female breast size and natural variation thereof in human beings?
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60 views
What are the differences between internal organs between sub-saharan Africans and Northern Europeans
Lets take as examples a typical Norwegian and a typical Nigerian.
In terms of human anatonomy the outer differences are more obvious e.g. (on average)
White skin vs dark skin
Pointy nose vs broad ...
1
vote
1answer
33 views
Does cartilage connect to other cartilage?
In the definition of a Ligament in Oxford states:
A short band of tough, flexible fibrous connective tissue which
connects two bones or cartilages or holds together a joint.
the wording of "two" ...
3
votes
1answer
70 views
True anatomical/physiological explanation for “metaphysis” etymology
The anatomy textbook1 I use for my students states that the prefix meta- means "between:"
The metaphyses (me-TAF-i-sez; meta = between; singular is metaphysis) are the regions between the diaphysis ...
1
vote
1answer
57 views
Why is there disagreement on the number of surfaces of the human heart?
I am finding that some state that there are 5 and some that say that there are 3.
For example, "Cardiology: An Integrated Approach" that was published in 2018 states that
There are 3 surfaces of ...
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0answers
17 views
What's the function of vitelline circulation in human embryo?
Why do we need a vitelline circulation if we already develop a placenta to gather all the nutrients we need?
Is it an evolutionary remain?
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0answers
30 views
How much blood do we have when the heart first starts to beat?
How much blood do we have when the heart beats for the first time?
It should be between the third and fourth week of embryonic life.
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0answers
18 views
Reflex muscular activity in three months old fetus
At the end of the third month, reflex activity can be evoked in
aborted fetuses, indicating muscular activity
This quote is from Langman's Medical Embriology.
Have I misunderstood it or it is ...
7
votes
1answer
180 views
What does lymph actually look like?
I have scoured Google and a number of my anatomy textbooks for a picture of lymph. However, I cannot find any such photo (or video) showing its actual appearance.
Can someone provide a reputable ...
1
vote
1answer
70 views
Why does smoking change the human voice?
What happens to the biology of the voicebox of smokers?
Women's voices can change to croaky men's voices, and vaper's voices develop "white noise" content, like a TV set to static, compared to their ...
0
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0answers
15 views
pH on skin penetration of salicylic acid
I have found that at lower pH, there is more free salicylic acid (due to pKa of roughly 3), which is neutral/uncharged and then can penetrate the skin's oils which are non-polar.
At higher pH, more ...
5
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0answers
45 views
How does salicylic acid (2-hydroxybenzoic acid) break down desmosomal proteins to exfoliate skin?
I've been searching for an explanation to salicylic acid's property of being able to break down desmosomal proteins, such as desmogleins in order to disrupt the outer layer of skin.
Can someone ...
2
votes
1answer
39 views
What are the differences between the margins of the lateral and medial condyles of the tibia?
During an osteology lecture about the bones of the leg, the professor mentioned that the posterior (i think it was the posterior at least, I didn't write my notes down very well) margins of the ...
1
vote
1answer
59 views
Does the cranial dura consist of the periosteum? and if not, then is there a mistake in my textbook?
My textbook (Neuroanatomy an illustrated colour text) states that:
The spinal dura and much of the cranial dura are separate from the periosteum, which forms the inner lining of the surrounding ...
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0answers
30 views
Biological & Evolutionary Reasons for Palm (Bi)Symmetry
The fingers of the human palm exhibit a (bi)symmetrical pattern with regards to their size, in the sense that the thumb and the pinky are almost the same size, and the same holds for the index and ...
0
votes
1answer
53 views
How does energy conversion happen (chemical to mechanical?) in moving body muscles?
From my understanding, the brain sends electrical pulses through neurons to different part of the body to initiate a movement. My question is, how is the movement realized? For example, in a train, ...
3
votes
2answers
83 views
Why do red muscle fibres have more mitochondria than white muscle fibre but less ATP than White muscle fibres?
This is a question given in my Anatomy book and I am really confused because logically the substance which have more mitochondria should have more ATP as mitochondria is the power house of cell.But ...
1
vote
1answer
34 views
Human Anatomy and Physiology - The Muscoskeletal System
In the human limb skeleton can you identify a bone which is rather feeble and does not have much role in supporting body weight or maintain posture, and doctors use pieces of it to transplant to other ...
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0answers
20 views
Does any tendon in humans receive a high amount of blood supply? Or is the property of not receiving a large blood supply a constant across tendons?
I read on https://www.physiocomestoyou.co.uk/blog/all-you-need-to-know-about-tendons/ (mirror):
[Tendons] do not have a large blood supply.
Does any tendon in the human body receive a high amount ...
1
vote
1answer
30 views
Can the word phalanx also be used to describe the finger bone plus the soft parts around the bone?
I was talking in an SE chatroom about fingers, and not being a native English speaker, I had to look up the word used for the part of a finger from the tip to the closest knuckle. I came across the ...
0
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1answer
151 views
What are the coverings of femoral hernia?
It was my Viva question and I was really puzzled.I know what is femoral hernia and it route like the abdominal content moves down the femoral canal and further through the saphenous opening and all ...
0
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0answers
52 views
Human femur maximum strength
In this video https://www.youtube.com/watch?v=os98s9kBlOI it is demonstrated that a moose leg bone can support until nearly 10 tonne before break. Is there any similar demonstration on human femurs? ...
1
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1answer
82 views
Are there any benefits/disadvantages/traits from having a permanent lower core temperature?
My body temperature as far as I remember has always been around 35.6 degrees Celsius, that's a degree less than what is the usually quoted as the average temperature for humans.
Are there any known ...
2
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0answers
44 views
Medical terminology for asymmetrically-shaped paired body parts?
Some people have different sized feet [source], a limb that is slightly longer than the contralateral (on other side of the body) limb [source], or other instances of paired body parts being different ...
2
votes
1answer
33 views
can auditory/ocular reflexes exist?
In the same way the knee-jerk reflex is a thing (I think the nerve signal doesn't go through the brain?), can stimuli received by the eyes or ears trigger "instantaneous" (faster than the brain can ...
1
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0answers
33 views
Can we “learn” reflexes?
Can we force our bodies to react to situations faster than our brain can think about them?
Some reflexes I can think of off the top of my head:
knee jerk reflex
retracting hand when touching a hot ...
0
votes
0answers
23 views
Is medullary cavity totally absent in clavicle?
In one of my books it said that medullary cavity is totally absent in clavicle but is it completely true ? One of my teachers said only the medial 2/3 of clavicle has a medullary cavity.
2
votes
1answer
75 views
What forms this pad on the side of the face?
I've been trying to figure out this for the best portion of this morning, but what structures are responsible for the pad highlighted in red? (sorry for low quality of picture, was just watching the ...
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0answers
41 views
Where would I point to if I wanted to indicate the location of the anterior insular cortex?
I understand research suggests the anterior insular cortex is where human empathy originates. The images I found researching the location of the AIC
do not give me a clear sense of where it is in ...
1
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0answers
71 views
What are the sufficient criteria that make an entity a living homo sapiens? [closed]
When I say criteria I mean like x biological functions or y genetics.
If it were to be appearance,anatomy. A corpse completely looks like a man.
Moreover a person who has had their 4 limbs amputated, ...
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2answers
162 views
Why does flicking a finger generate so much more force than extending it quickly?
Flicking a finger (holding it back with e.g. the thumb while building up "pressure" against the thumb, then releasing) is much more powerful than just uncurling the finger quickly.
I tried to do the ...
2
votes
1answer
304 views
Why are human bones usually curved?
Is there any simple explanation as to why human bones are more curved than straight and are thicker at ends and thinner in the middle?
2
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2answers
170 views
Why don't we speak of medial and lateral rotation of the forearm? And pronation and supination of the upper arm?
Why don't we speak of medial and lateral rotation of the forearm?
I notice we speak of forearm supination and forearm pronation, but why not medial and lateral rotation.
It seems to me that if we ...
3
votes
1answer
40 views
Surface perception
I'm looking for research studying:
How small and compressed together do particles of a surface need to be to be perceived as solid surface to human touch? E.g. sand still feels grainy. Has there been ...
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0answers
33 views
Are your finger muscles and tendons interconnected?
Are finger muscles and tendons interconnected? If they are interconnected, then if i exercise one finger will it train the other fingers since they are interconnected and share the same muscles in the ...
1
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0answers
54 views
ATP and Muscle Contraction
I have a question regarding how molecular interactions manifest in physical actions - such as hanging from a bar. To the best of my understanding, when it comes to the contraction of muscles, ATP is ...
1
vote
0answers
130 views
Movement of the Thoracic Cage During Movements of the Thoracic Spine
Just for a bit of context: I am trying to create a 3D digital model of the human skeleton as the first step towards computer generated muscle simulation, and as such I want the skeleton to be as ...
0
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0answers
32 views
For how long can the heart be in asystole and then restart itself?
The medication Adenosine is used for the treatment of some abnormal heart rhythms. However, according to Wikipedia, it can cause asystole for a few seconds:
Because of the effects of adenosine on ...
1
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1answer
140 views
Passing out from drowning [closed]
How long does it take to pass out from oxygen deprivation? The person is panicked and screaming so they accidentally breathe water into the lungs. So how long would it take for them to pass out? After ...
1
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0answers
29 views
For each movement performed by both the gluteus minimus and medius, what percentage of the movement do the gluteus minimus and medius account for?
From what I read on Wikipedia, all functions of the gluteus minimus are mirrored by the gluteus medius. Additionally, the gluteus medius is larger than the gluteus minimus (see comparative images here)...
1
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1answer
42 views
Does a full tear of the gluteus minimus tendon result in a long-lasting inflammatory response?
Does a full tear of the gluteus minimus tendon result in a long-lasting inflammatory response?
This answer mentions:
An isolated gluteus minimus tear still causes functional problems because of ...
1
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1answer
44 views
Does a full tear of the gluteus minimus tendon has any functional implications?
From what I read on Wikipedia, all functions of the gluteus minimus are mirrored by the gluteus medius. Additionally, the gluteus medius is larger than the gluteus minimus (see comparative images here)...
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1answer
52 views
How many different states can the femur and lower limb be in?
Often the knee can be thought of as a hinge joint. However, when it flexes, the knee permits the lower leg to rotate. So it is not a pure hinge joint in absolute sense because it permits more range of ...
11
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2answers
3k views
Where can I find the list of all tendons in the human body?
https://www.healthcentral.com/article/aging-can-take-major-toll-on-womens-tendons (mirror) claims that:
There are about 4,000 tendons throughout the body.
This claim is echoed by a fair amount of ...
0
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0answers
136 views
What is the significance of different types of papillae present on tongue?
Fungiform, Circumvallate, Filiform, Foliate Papillae are present on the surface of the tongue. They have a role in increasing surface area for taste buds that can be accommodated on the tongue. Each ...
