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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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220 views

Are there any place in human body that safe to implant things and have large amount of blood run through?

Suppose there was a fuel cell in the size of AAA battery that could convert human blood sugar into electricity. Assume it safe and efficient without causing allergic reaction. But to avoid the risk of ...
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0answers
15 views

Muscle layers of pharynx and gi tract

Why does pharynx have an internal longitudinal muscle layer and external circular muscle layer, while oesophagus and the rest of gastrointestinal tract have inner circular and outer longitudinal ...
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0answers
16 views

Tensile strength of collagen?

Really specific question, but what is the average tensile strength of human collagen, type I? I've tried looking for it online, and either my google-fu skills are weak, or I'm just unlucky. Also, is ...
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0answers
16 views

In endochondral bone formation, why does only hyaline cartilage get ossified to form bone?

There are three types of cartilage: hyaline, fibro cartilage and elastic. Fibro cartilage does not have perichondrium...so it does not take part in ossification because perichondrium needs to develop ...
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0answers
26 views

Why are oil glands next to hairs in skin?

today I saw this picture and I saw an oil gland next to a hair. I was wondering what is the use, it came to my mind that it's to make the skin slide over the hairs while they were growing outwards. ...
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0answers
4 views

Lacrimal caruncle

What anatomical structre sits behind the lacrimal caruncle? Is there also part of the eye or something different like conjunctive tissue? In short: Does the lacrimal caruncle also covers parts of the ...
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0answers
23 views

Why do humans lose subcutaneous fat from the extremities with age?

Why does fat tissue die and shrink on the hands, knees, and lower legs of most people as they age, even when they are overweight? In most people, their bone definition becomes much more visible around ...
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2answers
158 views

Can a brain dead person recover?

Many times I have heard someone having to pull the plug because the patient was declared brain dead before the body healed fully? Why do they pull the plug without first waiting till the body/brain ...
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0answers
21 views

Why are there sporadic lightly pigmented hairs in facial hair?

My body and scalp hair are entirely black. Until recently, I thought this was the case with my facial hair also, until I noticed a small handful of hairs that were anywhere from light brown to copper-...
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0answers
316 views

What is the occipital bun, precisely (in Neanderthals and Homo Sapiens)?

I've read that the occipital bun is an anatomical feature of the Neanderthals, and only because modern humans (except sub-Saharan Africans) carry a few percent of Neanderthal DNA due to ...
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1answer
34 views

Viral susceptiility of Nose and eyes

I read that opening in our face like nose and eyes are one which get us infected with numerous communicable diseases like cold , flu ebola etc. Both these organs have preventive mechanism like nose ...
4
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1answer
60 views

Why is the hippocampus considered to be a cortical structure but not the amygdala?

I'm having some trouble understanding the anatomical differences that classify the hippocampus as a cortical structure but not the amygdala. I have included the screenshot of a diagram from Gray's ...
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1answer
37 views

Polar renal scarring in pyelonephritis?

Why does infection and scarring occurs at poles in Vesicoureteric reflux but not in Obstructive pyelonephritis? It is said in Robbins that, it is due to polar papillae being flattened or concave ...
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1answer
125 views

Do breasts size depend solely on fat amounts?

I've read the first answer here on quora and it suggests that (not during pregnancy and breastfeeding) breasts differ in size only due to the amount of fats. However, there can be firm or soft breasts ...
3
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1answer
51 views

Do decibels matter if the sound is outside human hearing?

I bought a dog training device that emits sound at 25K hertz and 130 dB. Can this damage anyone’s hearing since they can’t hear it? Also is it possible for an infant to hear in the 25K hertz range? ...
3
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1answer
50 views

What parts of the visual system could be responsible for a fixed, monocular scotoma?

Light enters the cornea, crosses the lens, hits the retina. Electric sinal travels from retina through the optic nerve, reaches the chiasma, crosses and makes its way to the visual cortex. My ...
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1answer
26 views

Normal value range for Hematocrit

Normal hematocrit value 47% +-5% for men and women 42% +-5% what does this mean? Does this mean a deduction or addition of 5 from the main value is normal? I’m so confused thanks for any help.
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0answers
18 views

Why crackling the limbs in stretching?

In severel times I hear crackle nois when I stretch my limbs after a long time immobility. What cause this noise? Is there any connection with immobility or other (un)activities?
3
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1answer
252 views

Ligaments at the posterior superior iliac spine

In Causes of Back Dimples, it was determined that these 'Dimples of Venus' are created by a short ligament stretching between the posterior superior iliac spine and the skin. They are thought to be ...
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1answer
24 views

Why does the right bundle branch not have any terminal filaments in the IVS of the human heart?

Dubin's "Rapid Interpretation of EKG's" briefly describes this part of human physiology but doesn't explain the reason behind it. Is there a specific advantage of the human heart having this ...
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0answers
57 views

Where does the human brain drain to?

When a brain has a aneurysm and the patient survives untreated then where does that blood drain to or how is it absorbed? How is the pain perceived?
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0answers
38 views

Why do humans have digestive system present at front and kidneys back?

Outlet of digestive system is present at back of the body but its digestive system at front. Outlet of urinary system is present at front of the body but its system present at back. Why do humans ...
0
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1answer
40 views

Why do scabs itch?

I have noticed that scabs formed over wounds itch a lot. And if the scab comes off then the skin rarely completely heals and a scar is left. Assuming scabs are important for the healing of skin ,...
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0answers
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Describing the location of the thalamic adhesion in simple English

I'm trying to describe the location of the thalamic adhesion as part of a personal project. I can't reference pictures, and I need to be as precise as possible without using convenient anatomical ...
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1answer
166 views

Ventricular Filling : Systole or Diastole?

As the Blood goes down from the Atrium to the Ventricles: The Tricuspid Valve ( Right Atrioventricular Valve) Bicuspid Valve (Mitral Valve ) The atrial pressure is INCREASES WHEN ATRIA ( THE ATRIA ...
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0answers
17 views

Exhaustion of skeletal muscle and ligaments

I read somewhere that while doing lifting back should be straight(means normal curve), so that erectors muscle in back do the work but it gets tired easily. Hence we form curve on our back like when ...
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0answers
18 views

Why do we feel numbness and an electric sensation in our legs after standing for too long?

We have all felt that numbness while standing immobile for a while.It gets difficult to walk.It can also happen if we are just putting some pressure on our legs Why does this happen? I'd like to ...
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1answer
46 views

does the amount of blood circulate in a body is same before and after amputation?

if a person loose his hand in an accident do the blood flows through his body is equal to the volume of blood before accident? how human body manage with that blood which is deserved by the missed ...
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2answers
4k views

Many black people I've met have bigger lips than white people, why? [duplicate]

I noticed that many black-ish people I've met have bigger lips than the white-ish people I've met. However, not all black-ish people have big lips. Is there any explanations in terms of natural ...
2
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2answers
75 views

Why do I have two kinds of pubic hair? [closed]

I feel silly even asking this question, but there's a quirk of my anatomy that I find interesting, and I can find nothing about it online. I am looking for information on whether this quirk is ...
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1answer
33 views

Are releasing-hormones and release-inhibiting hormones from the hypothalamus ever present in the blood?

Our teacher said that these two hormones are normally never present in the blood stream, and to be carfeul of it if it comes as a question. I'm not conviced to be honest, is this true?
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0answers
26 views

Are asian eyes better at sun protection?

Today I have visited a very popular tourist place in Tokyo. It was a very sunny weather and there were HUGE crowds of Japanese tourists and I was one of very few Europeans. I have noticed a surprising ...
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0answers
38 views

What secretes the pericardial fluid that protects the heart from the contraction's friction?

As you guys know, the membrane that protect the heart is the pericardium, which consists of 1) The serous pericardium, which is divided into visceral pericardium and parietal pericardium, secretes ...
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0answers
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Understanding hyper- vs hypokalemia

After searching the web for a while, I found that: Hypokalemia results in a prolonged Q-T wave interval Hyperkalemia results in a peaked T wave and a wide QRS complex Now, I'm trying to understand ...
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0answers
11 views

How far into the periphery does the dura mater extend and how does it terminate?

The dura mater surrounds the central nervous system, but it does not surround peripheral nerves. Where does the dura mater "stop" and how is the CSF kept from leaking out in the periphery? Where is ...
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1answer
51 views

Anatomy of joints of human hand

Q) A girl slipped and is falling. She puts out her arms to prevent falling. Which joints are most affected by her fall? Fibrous and Synovial joints. Cartilagenous and Synovial joints. Fibrous and ...
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1answer
24 views

Using formulas to explain why contraction of blood vessels leads to increased blood pressure

I know, I know this is probably a question too simple to be asked on a forum like biology stack exchange. Problem is, I looked many places and can't seem to find a more mathematical approach to ...
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2answers
59 views

Are all of our hormones synthesized in the same gland that they are secreted from?

For example, growth hormone is secreted from the anterior pituitary; is it also synthesized there?
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1answer
95 views

Why hasn't evolution gotten rid of the appendix yet?

A figure I have recently stumbled upon suggests that about 7% of the world population will, or have, had appendicitis in their lifetime. Cutting out the appendix was impossible until very recently. ...
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0answers
32 views

Are there examples of sexual selection effecting traits in both sexes equally?

I've had an ongoing interest in the evolution of human furlessness and this appears to be a notable example of attributing a trait that effects both sexes to sexual selection. Darwin suggested it was ...
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1answer
47 views

What is the difference between how motor function is controlled in cerebrum vs frontal lobe?

At least according to wikipedia, the frontal lobe houses the primary motor cortex, but in a different article about the cerebellum, it says the cerebellum controls motor function. So, do both parts ...
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1answer
70 views

How can I verify my true genetic relationship with my close relatives with simple physical traits?

Question I don't know if it is ethical to ask a question like that, but I would like to know every simple physical trait that I can observe on me, my parents and my siblings which are regulated by a ...
2
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1answer
44 views

Is there human Anatomy software that provides great detail?

Is there Anatomy software that is exact representation of human body, like let's say virtual reality tour inside human body from head to foot, detailing all organs even small, covering all systems, ...
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0answers
50 views

Are there wounds which never completely heal?

I have a cut on a knuckle which occasionally opens (usually during winter), to disappear after some time (it is usually fine during the summer). This is going on for years now and yes, I will show ...
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0answers
15 views

Ingestion of cellulose digesting prokaryotes? [duplicate]

If humans digest cellulose digesting prokaryotes, can we start digesting cellulose like cows?
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1answer
190 views

HOW is the Gallbladder attached to the liver

The gallbladder’s function is to store bile from the liver which is delivered through the cystic (bile) duct. The cystic artery is also connected to the gallbladder to deliver blood. (Correct me if ...
0
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1answer
579 views

Why can't we move our toes and some fingers separately? [duplicate]

In our feet, other than the large toe, the other toes cannot be moved separately. If we try to move them, then all the four toes move together. We cannot move each toe by itself. Same thing occurs in ...
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2answers
43 views

Why do we have only one elbow per arm and one knee per leg, not multiple elbows or knees? [closed]

I was surfing on the internet for a long time, but I couldn't find the answer to my question: Why do we have only one elbow per arm and one knee per leg, not multiple elbows or multiple knees per limb?...
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1answer
4k views

Do women tend to have longer legs and shorter torsos than men?

I've always heard that women tend to have a greater leg length to torso length ration than men, and I think that my anecdotal observations of pedestrians of both sexes tend to confirm that. However, ...
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0answers
32 views

Why is the head/neck of the femur at that 120-150 degree angle?

I'm just wondering why the femur is such that there is that head and neck sticking out of the top at an angle, why it isn't just straight up into the hips?