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2

It is yet to be discovered by scientists. But there is a new study that finds that brain cells called astrocytes supply the urge to sleep by releasing adenosine a chemical known to have sleep-inducing effects. The chemical accumulates in the brain during waking hours, eventually helping to stimulate the unique patterns of brain activity that occur during ...


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Let's go step my step here. Going by your notation I'll call the square as Male and Circle as female. So from this information I can confidently say that you disease is not X linked dominant. Why? Because Females carry XX, that would mean to be X linked dominant she had to be X'X' for the disease allele to manifest it's phenotype. But if it were X'X, it ...


1

The concentration of K+ inside the cell is 30 time more than outside. Hypoxia causes loss of this intracellular Kalium and consequent/premature repolarization when measuring the potential of action. As the all the ECG theory is Vector based, any abnormality in the electric pathways and myocytes will result in changes of ECG. This picture depicts the ST ...


4

The methodology behind homeopathy is scientific nonsense. If you dilute anything a billion times, it will have no chemical effect, not even if you shake it all the while. So no, homeopathy does nothing for cancer, or any medical condition at all. Of course plants can have active compounds in them, once scientists have identified those compounds, they can ...


5

Sexual arousal is a very complex response, that includes a whole range of physiological changes, firing of lots of neural pathways, increased muscle tension, elevated heart rate with increased blood flow to the skin, primary and secondary sexual organs and a whole lot of hormonal spikes. Sexual desire is defined as the behavioural drive that motivates ...


1

I am not an ENT doctor, but I think the following diagnoses would suffice to determine each of the conditions: Blocked Eustachian tube: Complaints would be of sudden onset and likely associated with a common cold, or ear infection. Providing the patient with standard decongestant should provide quick relief. Ruptured eardrum: Patient should have subtle ...


6

Short answer Image blur on the retina is the most important monocular cue for lens accommodation. Background Focussing of an image on the retina is mediated by the lens. Re-shaping of the lens to focus the image on the retina is called accommodation. In general , the main cues for focussing are retinal disparity and blur, and to a lesser extent proximal ...


1

No not necessarily. Cancer can also be caused by bacteria and viruses in your body The regulation of cancerous tumor development is converged upon by multiple pathways and factors. Besides environmental factors, gastrointestinal (GI) tract cancer can be caused by chronic inflammation, which is generally induced by bacteria, viruses, and parasites. The ...


2

Often genes or other DNA fragments are inserted into an expression vector and used to transform bacteria or other cells. When a mixture of vectors is used containing various DNA fragments (e.g. a chopped-up genome), then individual (bacterial) colonies need to be isolated to make sure they carry only one insert. This can be done, e.g., by plating the ...


0

The problem is the glucosepane bond is very strong, hence the molecules which would break this bond need be necessarily toxic and damaging to other molecules in the body. Glucosepane breakers already exist, but they are too toxic, and perhaps all will necessarily be that way. All hope is not lost however. Other very effective medical drugs (like clot ...


4

Yes, such a conditions exists. It is called "situs inversus" (literally "inverted sites"). All major organs are placed on the opposite site, the condition is relatively rare with an incidence rate of 1:10.000. There are some even rarer forms occuring, when the organs are flipped, but the heart is still on the left side (levocardia) as opposed to the case ...


2

Glucose is the only fuel normally used by brain cells. Because neurons cannot store glucose, they depend on the bloodstream to deliver a constant supply of this fuel. Fatty acids do not serve as fuel for the brain, because they are bound to albumin in plasma and so do not traverse the blood-brain barrier. In starvation, ketone bodies generated by the liver ...


1

The reason for the decay are ever evolving bacteria, which happen to be very hard to overcome, even nowdays. There is a lot of research centered towards protein interactions, even mapping whole interactomes, which would help us get rid of decay, yet naturally our system wasn't able to evolve as fast as technological advances, but bacteria did.


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No, it wouldn't. In order to understand why, you must understand that Genes are translated independently of one another. The ribosome starts translating at a start codon (ATG) and stops at one of the three stop codons (TAG,TAA and TGA). Whether another gene has a frameshift mutation or not, does not affect the current gene in any way. The ribosome will ...


3

For transcription, the cell uses different signals from start- or stop- codons to determine the start and end of a transcript (see this wiki page). Codons (and hence frameshifts) are only relevant at translation of the mRNA to protein. Frameshift mutations occur in coding sequence, so the promoter and termination signals for transcription are unaffected. ...


3

First of all, for a frame shift mutation to occur nucleotides (not amino acids) are either deleted or inserted into the sequence. Read about details on this wiki page. Here's an image about frame shifts. On panel A a new stop codon is formed (TAG is trasncribed to UAG that is serves as stop codon during translation) thus the result is an abnormally short ...


-1

Here is a simple answer, if you want it. Eating salt raises the amount of sodium in your bloodstream and wrecks the delicate balance, reducing the ability of your kidneys to remove the water. The result is a higher blood pressure due to the extra fluid and extra strain on the delicate blood vessels leading to the kidneys.


1

National censuses are collected, published and disseminated primarily by each country's census or national statistical office (NSO) or its equivalent. Census data are published in each country's vernacular, and as appropriate, many offer English as well as other language versions. Statistical offices of international agencies (e.g. United Nations, ...


0

According to wikipedia and MedlinePlus muscle cramps can be caused by muscle overuse or injury or dehydration and lack of minerals (eg. potassium or calcium). In this wikipedia page you can read about the mechanism of muscle contraction. I'd emphasize and quote the most important parts here: ATP binds to myosin, allowing it to release actin and be in the ...


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According to this website: http://www.spirometry.guru/fvc.html it causes difficulty with inhalation but exhalation is normal... "Typically the expiratory part of the F/V-loop is normal: the obstruction is pushed outwards by the force of the expiration." "During inspiration the obstruction is sucked into the trachea with partial obstruction and ...


3

The spicy feeling essentially is the feeling of pain. It is caused by the molecule Capsaicin (https://en.wikipedia.org/wiki/Capsaicin) binding to the ion channel TRPV1 (https://en.wikipedia.org/wiki/TRPV1), activating it. You can temporarily get rid of the pain by cooling (as you would with any other injury) - hence the effect of ice. Unfortunately, this ...


4

I don't understand your calculations and I don't understand why you're trying to use Bayes formula. I don't know the $\frac{1-p}{2-p}$ formula and I don't understand what it is supposed to calculate. It seems to me that you're overthinking a simple problem. We don't have all the information and need to make a bunch of assumptions but if I understand the ...


1

Short answer: Due to habituation. You do something enough number of times, then that event ceases to be something new, and your body adapts to it. In this case, you train your body to accept more risks allowing greater lengthening, before it begins to internally signal the muscles that an injury is incoming. Read below for the slightly longer version: ...


0

It is not possible that one of the valve is completely closed and the person is still alive without being in ICU. I think what the doctor was trying to communicate to the patient was that one of the valves is in the process of complete closure. There are three main types of diseases associated with heart valves :- 1- Blood flows backwards 2- Heart valve ...


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Genetic view of adaptation: Do note that this is looking at the view from the POV of a gene. Please read the comments below this answer, for a small discussion on the kin selection hypothesis. Do note that I do not study evolutionary psychology, or work on the level of the population. This is a bit of a misconception, as nature really doesn't work like ...


2

Its down to the structure of your eyes. The eyes are made of rods and cones, which have difefrences in detecting light. Now, compare the images below. As you can probably see, the peripherl vision is predominatlty due to your rods, and your central vision made of cones. Measured density curves for the rods and cones on the retina show an enormous ...


0

Because peripheral vision uses the peripheral retina,which has mostly rods as photoreceptor,while central vision uses the foveola,a central part of the retina which mostly has cones as photoreceptors. Rods are more sensitive to light. That is why they are more efficient in the dark.


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Although this question sounds easy to answer in the first place, it is not. The main problem between humans and the apes we are most closely related to is that we have 46 chromosomes, while the apes all have 48. At some point in the evolution of the humans the ancestral chromosomes 2 and 4 fused together to form our chromosome 2, leaving us with only 46 ...



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