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16

No, it can't be done for a lot of reasons. Here are just a few. 1) Memories are stored in electrical pathways, not the the cells themselves. You don't have 1000 memories in a chunk of brain that contains 1000 neurons. If you don't get the entire pathway, you won't get the memory. 2) Once a nerve is cut, it won't fuse with another cut nerve. All you'll have ...


11

The need for birth control has been a concept for thousands of years and remains an important issue for men and women today, the need for contraception helped humans to achieve control over our population and healthy sexual relationships without having the fear of pregnancy. The medieval contraception methods mostly relies on plant based oral ...


7

Individuals have not only hand dominance but also a dominant foot, eye and ear. There has also been a belief that this sidedness applies to chewing as well. However, the short answer is that no one is sure, but that it may be related to handedness. I only looked at studies done after 2000. One large study[1] found a questionable to weak correlation, not ...


7

The developmental growth of bone tissue is hormonally controlled. It is, as far as I know, not under direct neuronal control. Before reaching adolescence, the long bones (mainly in the arms and legs) grow in the epiphyseal plate, the area of the bone where cartilage is formed and ossified on the diaphyseal side, thereby lengthening the bone. The longitudinal ...


6

This is an interesting question, which has not been answered yet. It is also questionable, if this protective effect is present at all. There are around 40 studies on the topic available which have subsequently undergone meta-analysis. In a meta-analysis all data from recent studies which meet certain quality criteria are analysed together. This gives a much ...


6

Hair does not grow back thicker when it is cut. This is somewhat of an optical illusion because when you shave with a razor it leaves the top of the hair flat rather than pointed so it appears thicker. For instance see this picture: As you can see the hair is tapered at the top and when cut loses this taper to leave a large cross-sectional area. I would ...


6

Gluten is a protein. The textbook answer is that protein is not stored in fat cells. Proteins are hydrolyzed into amino acids through digestion; some amino acids are ketogenic, and can contribute carbon towards fat biosynthesis. So some of the carbon that originates in gluten may be incorporated into a fatty acid. But the carbon has no 'memory' of its ...


6

Questions of the type, "why does organism X have feature A?" invite teleological (just so) explanations which are difficult to substantiate. For example, the number of teats on a cow are difficult to explain in terms of providing milk to humans! We should look to evolutionary history to explain human traits, not "just so" stories. The simple answer is that ...


5

Via deep scientific analysis (i.e. trying it myself 5 seconds ago), I have determined that you can in fact speak while breathing in, it just sounds funny. Think of the vocal chords as being like the body of a flute. As air passes by them, they vibrate and make sounds. Through careful modulation of their shape, specific sounds can be reproducibly made (this ...


5

As you noted, the cornea needs oxygen, yet it's not vascular. It needs to get it's oxygen supply from diffusion. In the daytime, diffusion occurs from air through the tear film covering the cornea. The cornea spends about a third of it's lifetime under closed lids. At night, the tear film remains intact and is continuously replenished. The inner aspect of ...


5

Oocytes, or immature female eggs, develop in the fetus's ovaries during pregnancy. This graph (U. New South Wales) shows the oocyte population over time in a human female: Although the x-scale is kind of confusing (months when negative, years when positive), you can see that the fetus has all the oocytes it will ever have at the peak 18-22 weeks after ...


4

Limb lengthening surgery is usually used to treat sequelae caused by bone disease, trauma, pygmyism or inflammation. I personally do not recommend to use surgical methods to increase height. Typically Limb Lengthening requires Achilles pre-lengthening surgery and a lot of postoperative rehabilitation. Moreover, Limb lengthening surgery may cause pain, ...


4

First of all, this observation is the norm across human perception. While humans react in roughly the same way to similar stimuli (e.g. both a cranberry and a tomato are seen as red, the destruction of tissue is felt as painful), the intensity tends to be different. Also, many stimuli elicit not just a knowledge of the state of the world or one's body, but ...


3

The following is one of the many elegant statements in General Anesthetic Actions on GABAA Receptors: It is the fervent view of the authors that general anesthesia is no different from any other pharmacological process: exogenously administered drugs interact with key sites on cellular proteins in the body which results directly in the alteration in the ...


3

Clonidine is an agonist on the α2 receptor... but then again norepinephrine is also an agonist on the α2 receptor. Then the physiologic ligand of the a2 receptor, norepinephrine is autocrine (meaning it is released from a cell then binds on a receptor on the same cell) causing negative feed back and it inhibits further release of norepinephrine from the ...


3

In doing search into muscle stem cells, I found some articles which discuss roles of satellite stem cells and non satellite cells involved in muscle regeneration: (Yin, Price and Rudnicki, 2013,Seale and Rudnicki, 2000, and Mitchell et al, 2010). Other articles, that I found discussed the splicing of insulin-like growth factors (IGF-1) into the satellite ...


3

This is a myth which most likely came from methological flaws in the original study. It could never be reproduced. This paper ("Darwin’s Legacy: An Evolutionary View of Women’s Reproductive and Sexual Functioning") deals with it. The interesting part starts from page 30 and says (the references can be ressolved in the article): Critiques of MSH Studies ...


3

Balance is tricky and depends on a lot of things, including, to some degree, your sight. Balance is achieved and maintained by a complex set of sensorimotor control systems that include sensory input from vision (sight), proprioception (touch), and the vestibular system (motion, equilibrium, spatial orientation); integration of that sensory input; and motor ...


3

Skin is safe to chew, and digestible. Fingernails are not digestible, so really shouldn't be swallowed if avoidable. In the medical literature, there are at lease 225 cases of foreign bodies in the appendix. They include: a metal drill bit that was ingested unintentionally 3 months earlier pins (81 cases) lead shot (81 cases) seeds (34 cases) bones (16 ...


3

The reason for this worry is chemical--as water warms up, more contaminants can dissolve in the water. With water pipes specifically, people worry about lead contamination. Modern pipes are not as likely to corrode (or even be made of lead) as old pipes, so this is more of a concern in older buildings. See this NYT article for more information.


3

This actually depends on how your tap water is warmed. If you have a personal water heater, which is connected to your tap with non-corrodable pipes, then there is essentially no difference. However, if the heating comes from a common source, then it would be very difficult to verify that the heater-tap connection does not contain any corrodable pipes. In ...


2

Interesting question! There has been at least one study that bypassed a spinal lesion site with autografted neuronal tissue (Tadie et al., 2004 - doi:10.1089/089771502320317069). The study participant regained voluntary motor skills 8 months after bypass surgery. The surgery involved the implantation of nerve autografts between the rostral spinal ventral ...


2

Embryonic cells "know" where they are relative to each other by chemical signals, same as in adults. These molecules are known as morphogens (specific examples include the sonic hedgehog and β-catenin). The amount of morphogen in a region of cells determines which gene gets turned on and thus what it develops into. And the amount varies by how far they are ...


2

I wanted to add some helpful references. The 6th edition of the Gilbert Developmental Biology textbook is available on NCBI bookshelf. It's a bit old (2000), but much of the information is still relevant. You can search this textbook for specific terms but not browse. There is also a collaborative science/fashion project between the Storey sisters, called ...


2

It seems that just a Russian researcher named Dr Alexander Teplyashin has made any progress into using stem cells for LL (Limb lengthening). Conventional way to go about it would always be surgeries which are detailed in Wikipedia (reference). This is a relatively new development, so I could not find any relative publications to support the claim of this ...


2

Condoms have been around for a long long time. Supposedly, condoms made from such materials as fish bladders, linen sheaths, and animal intestines where in use around 3000 BC (reference). Coitus interruptus was tried before that which may or may not be successful. Infanticide was also practiced where an unwanted child was born in ancient societies ...


2

Pyridostigmine is an analog of neostigmine, so has the same basic mechanism of action. Please forgive me for repeating information you may already know. There are two main families of acetylcholine receptors: muscarinic and nicotinic. Acetylcholine receptors at the neuromuscular junction (NMJ) are exclusively nicotinic (N1 or NM), so that's the only ...


2

Anger is a common emotion in most animals and it is highly related to stress. At time of anger body usually releases stress hormones and the body's way to respond to stress is by sympathetic nervous system activation which results in the fight-or-flight response. Anger is an emotional response related to one's psychological interpretation of having been ...


2

This paper, while mainly dealing with chronic nerve compression, appears to explain the effects of nerve compression on the blocking the transmission of neural impulses (causing the "sleeping limb" syndrome). This paper describes how the application of pressure on a nerve causes a miniature case of compartment syndrome, where the pressure causes the ...


2

You are correct that hydrophobia is often considered pathognomonic of rabies. However, I offer for your consideration: Hydrophobia as a rare presentation of Cotard's syndrome: a case report.1 Cotard's syndrome itself is a bizarre psychiatric condition that the authors of the above paper define well: Cotard’s syndrome is a rare condition where the ...



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