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Short answer The relative large surface area of the white sclera in humans has been linked to an enhanced ability to detect eye gaze. Background The white of the eye is caused by the sclera. Human eyes indeed have the highest relative amount of visibly exposed white sclera. The amount of visible sclera provides information about the orientation of the ...


6

In short, without direct physical evidence (forensic or medical examination), testimony, or documentation to act as proof, you are left up to the discretion of the court to determine whether evidence is admissible and up to a jury to decide if it is reasonable to presume that a person depicted is of a certain age if no other evidence to the contrary is ...


5

"Position of the pelvis" is pretty vague, but there are very clear differences in pelvic morphology between females and males. This sexual dimorphism looks like: Female pelves are wider and flatter, which I think you could tell from surface anatomy. Of course if you could palpate, then you could tell for sure.


5

There is quite a lot of misunderstanding about alcohol (and caffeine) as a diuretic. It's not nearly as cut and dry as you're presenting. There is no answer to your question. Sodium and water are very tightly regulated, and a lot has to go wrong before they fail. If alcohol could easily derail water regulation, there would be far, far fewer alcoholics in ...


5

In general, no. Car batteries are designed to provide a large amount of Amperage, to turn the starter with a high amount of torque via an electric motor. Generally this is done at 12 or 24 volts. The current recommendations for a defibrillator requires 200v, and a very small amount of amperage. This is one of three settings in a standard defib procedure. ...


4

Short answer There are no functional nociceptors present in the umbilical cord. Background Having had the opportunity to cut the umbilical cord of one of my kids, I can anecdotally confirm neither newborn nor mother gave any sign of pain during the procedure. That is, when cutting the umbilical after the birth of a full-term baby. The only person clenching ...


4

I would strongly question whether the underlying claim that testicular asymmetry is generally true. While there is no known clinical significance of testicular asymmetry, most men probably have no noticable difference in testicular size. There have been a number of studies over several decades, and findings have been inconsistent. Braus (1956) stated that ...


4

It is something of a misnomer to speak of CSF “circulation,” particularly in the spinal canal, as there is no continuous loop circulation of CSF as there is in the cardiovascular system. For quite some time, it has been known that CSF movement results from the formation of new CSF and motion of cilia on the surface of the choroid plexus and ependyma ...


4

There's really two answers to the question. The first is overall symmetry: mammals, like all tetrapods, are bilaterally symmetric. This comes from a distant common origin with other bilaterally symmetric organisms. Organisms which evolved from this common ancestor often have organs in pairs, probably evolving as a re-use of regulatory genes. The other ...


4

The female mammary gland tissue contains androgen receptors (testosterone is an androgen). So this tissue is sensitive to androgens, and they inhibit the estrogen-induced proliferation. The inactivation of the androgen receptor on the other hand leads to an accelerated growth of the pubertal mammary gland and to the upregulation of estrogen receptor α ...


4

Based on the location of that cross section in the upper arm the vein in question appears to be the basilic vein. The basilic and cephalic veins are the largest veins (most of the time) in the upper arm. Here is a nice diagram from wikipedia that shows both. The cephalic vein is much more superficial than the basilic vein, as you can somewhat appreciate in ...


4

According to this article appearing on the website of the American Association of Neurological Surgeons, gunshot injuries to the head are fatal in 90 per cent of cases. Many victims die before reaching the ER, and the 50 per cent who survive the initial trauma die in the ER.


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In the vertical plane, bending of the fingers is indeed referred to as flexion, while straightening is called extension. In the horizontal plane, spreading the fingers is called abduction, and approximation is called adduction (Fig. 1). Fig. 1. Finger movements and terminology. source: US Dept. of Veteran Affairs


4

I am no expert on comparative anatomy, but I will give this a shot. Please edit if you know more about this subject! The configuration of opposing elbow and knee joints is a feature we humans share with large group of mammals. For example, below is an image of a shrew skeleton. Opposing joints are course a major feature of mammalian anatomy, and there ...


3

This appears to be the sternalis muscle. The reason it is not mentioned may because it is not present in all individuals, and is therefore relatively poorly characterised. The image is from An Atlas of anatomy by regions by John Charles Boileau Grant. Another image of the muscle can be found in Pocket Atlas of Human Anatomy by Thieme:


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There is a model of an adult, male, real human brain here: http://brainder.org/download/brain-for-blender/ It can be imported into Blender or any other 3D application that can read Wavefront OBJ or Stanford PLY formats.


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The vertebral column is a bony, segmented structure that supports the torso/head and thorax. The spinal cord is a bundle of nerves that runs inside the structure of the vertebral column. So - they run together, but are completely separate.


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The vertebral foramen What is it, and what passes through it? A number of structures pass through the foramen. These are the root of each spinal nerve, dorsal root ganglion, the spinal artery of the segmental artery, communicating veins between the internal and external plexuses, recurrent meningeal (sinu-vertebral) nerves, and transforaminal ligaments. ...


3

According to this article female ejaculate is produced by the Skene glands.


2

CSF is actively pumped in an ebb and flow manner by the pressure with our respiratory mechanism transmitted through the pelvic diaphram onto the sacral bone that pulls on the spinal dural membranes attached at S2. Think about it: the pelvic and thoracic diaphragm are linked in a respiratory phasic contraction (confirmed with MRI). The pulling on the sacral ...


2

Blood pressure is mostly dependent on the height from the heart. Therefore, if it is below the heart it will have higher blood pressure and if it is above the heart it will have lower blood pressure. Here you are asking from two parts of body that have same height as the heart, so they will have approximately the same blood pressure. For more see: Netter'...


2

I don't think this is a complete answer, but I know that historically hair, like horse tail has been used as a part of armor, because it is flexible and difficult to cut through (see dragoon helmet picture). Protection could be one of the primary purposes of facial hair in human males, who are more likely to experience aggression or be hunters.


2

This is called achalasia. According to UpToDate, the mechanism for this diseases are generally unknown. What is known, however, is that the esophagus has a neural system called the myenteric plexus and if these ganglion cells in the esophagus are damaged in any way (e.g. physically, followed by Wallerian degeneration, or the primary process of degeneration ...


2

It is, of course, not just mammals, but nearly all animal life is symmetric. Even plants are usually symmetric in some degree. There are exceptions here and there. For example, one interesting exception is that of the fiddler crab which has one claw larger than another. In general, when a single appendage is present on an animal it is nearly always on the ...


2

It appears that the invagination of the renal kidney is vestigial from development and unlike human and other mammals, the bovine kidney does not form a smooth outer cortex. The kidneys of the bovine do not lose their foetal lobulation. -Renal Anatomy - Anatomy & Physiology en.wikivet.net However this is not related to its function. Despite ...


2

The comments on this question have pretty much covered everything I had to say. Generally, you're more likely to cause brain damage than an instant kill by shooting someone in the head, though it does depend on what part of the brain is hit and the kind of projectile being used. Normal small-caliber weapons pierce bone and tissue and that's about it. Small ...


2

Actually, the body goes into the fasting state about eight hours or so after the last meal, usually when the guy finishes absorbing nutrients from the food. Normally, body glucose, which is stored in your liver and muscles, is your main source of energy. When in a fasting state, your body uses up the glucose that you have stored to provide energy. If you ...


1

Based on Figure 11 in the original publication (scale bar = 10 cm): The anteroposterior length of the skull should be about 16.3 cm. I just printed out the figure and did the conversion. So check that your 3D printing software estimates a little over 16 cm for the length from brow ridge to occipital. The full reconstructed skull will be longer of course, ...


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From my research, I can deduce that the cranial volume for males is 560 cm3 (34 cu in) and 465 cm3 (28.4 cu in) for females Note: These skulls are approximately half the volume of modern human skulls average Homo erectus skulls are 900 cm3 (55 cu in) I don't think you would need the area for 3-D printing, but you can use the volume!


1

Since the argument with my girlfriend was finished days after this was posted(sadly we were waiting for this but it took so long, we posted this question to have an answer right away) I'll just post here what I conclude about the "big-boned theory" based on searching through internet. Let me site this link; that says, "However, the initial findings of ...



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