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10

Gluconeogenesis is not the reversal of the glycolysis, but the generation of glucose from non-carbohydrate precursors (like odd chain fatty acids and proteins). The reason why we have this process is because some organs and tissues can only use glucose as their energy source. These include the brain (although ketone bodies can be used here as well), ...


9

There's a very big difference between doing the calculations needed to simulate the human brain (or any animal brain FTM - we can do a fairly decent job on C. elegans.), and doing computations. While a basic leaky integrate & fire model is fairly simple, to ACCURATELY simulate a single neuron in real time takes a pretty fast computer. See e.g. these ...


7

When you travel to different time zones, your circadian clock will be off (incorrect). The reason your circadian clock will be off is because your body has adapted to the time zone you are from. When you enter a new time zone, your circadian clock will still be functioning on the old the time zone. If the time zone difference is $\pm 12$ hours, this is a ...


6

Riding roller-coasters usually (unless you are psycho) induces a release of adrenaline and other chemicals, like endorphin (your bodies pre-emptive effort to combat any possible pain and stress you may be about to experience), into your body. Endorphin is a strong chemical, specifically released to make you feel relaxed and confident. Obviously this explains ...


6

Medicine is not my field, but I want to point out two things: The former words have latin roots, and historically latin was the international language of science. Therefore, nomenclature in different scientific fields are often based on latin. The former words describe tissues and the related functions/processes (e.g. renal = kidney + related tissues + ...


6

So if you're reading the flowchart, understanding the notation of the arrows is important: We have rectangles around the gene products There's a circle, denoted by DNA, noting that the proteins are expressing the product that follows through interaction with DNA The solid line with an arrowhead means there's some sort of interaction The solid line with the ...


5

How do you define the biological limit? It very much depends on how you define a biological limit. If you prefer, it very much depends on how you define a human! Some women are completely sterile while others are highly fertile and there is genetic predisposition to that. How much "perfect" should the genotype of an individual be so that it is still ...


5

I did a quick search and found some research in this area. Sleep inertia is the technical term for feeling groggy for a while after waking up. In a review article by Patricia Tassi, Alain Muzet (Sleep inertia. Sleep Medicine Reviews. Volume 4, Issue 4, August 2000, Pages 341–353), they define sleep inertia as Sleep inertia is a transitional state of ...


4

Think this review from Nature can answer your question. A brief summary ( with slight simplification): The ascending activating system (that is responsible for wakefulness) has two branches: The first one ascends to the thalamus and activates the thalamic relay neurons - these transmit information to the cortex. They get their main input form two ...


4

It can be spread from human to human through urine but it is very rare seeing as we are relatively clean creatures (most of the time) and our excrement hardly ever comes into contact with other individuals without first being purified. Sources: Leptospirosis CDC: Leptospirosis infection


4

The redden area around the grayish-white indentation of the canker sore isn't filled with anything. This circular area is simply inflamed. The grayish-white area in the center is not filled with puss or anything else as well. This is an area of dead cells but underneath this layer of dead cells the tissue red [1],[2],[3]. Canker sores, Aphthous stomatitis, ...


4

TL;DR: Chymosin is similar to pepsin and I couldn't find any evidence of functional/expressed chymosin gene in human genome. It seems like a common misconception that chymosin is functional in humans. Already in 1940s it has been shown that rennin (aka chymosin) is absent from "gastric juice" in adult humans. Genetically there is only pseudo-gene for ...


4

The word density in the medical term bone density is used to quantify only the mineral content of the bone (bone mineral). It's not intended to describe the total mass density of the bone like we are used to from physics. This is all on wikipedia: http://en.wikipedia.org/wiki/Bone_density Thus, when one say that a Grizzly bear have 10 times the bone ...


3

First, there are three ketone bodies: Acetone (top), acetoacetic acid (middle), and beta-hydroxybutyric acid (bottom), see the illustration from the Wikipedia: The second and the third are taken up by heart and brain cells and then converted into Acetyl-CoA which is fed into the citric acid cycle where it is further metabolized. Acetone is mostly ...


3

Pathways in biology are very hard to interpret without being an expert in the subject. Here a link to The Standard Graphical Notation for Biological Networks that might help you understanding the notation used. Pathway are generally based on evidences of links between the players. These links do not require to be found using one particular technique. Those ...


3

Could it be beneficial to artificially induce fever in a person who has an illness if they are not already experiencing fever? No, not really. Pretty much the only use of hyperthermia in medicine is in the treatment of cancer. If you google "use of hyperthermia in medical treatment", you'll likely only find two kinds of hits: those for cancer treatment ...


2

Something I found: Jeffrey S. Dover,Clinical Associate Professor of Medicine at Yale University,said the exact reason for fingernails and toenails growth factor defference is still unclear. However, the growth rate of fingernails is indeed nearly 3 times to toenails'. Dover said that when the nails grow old, their growth rate may be slightly slower, but ...


2

Long-term exposure to excessive oxygen will lead to damage in pulmonary tissue. This damage resembles the same damage which is seen in patients with Acute Respiratory Distress Syndrome (ARDS). In these patients surfactant specific proteins are damaged by proteolysis. This proteolysis is caused by the neutrophil elastase enzyme, after a massive influx of ...


2

So, when they subjected "ready to drink" beetroot juice to thermal pasteurization, they found the betacyanin and betaxanthin (our major antioxidants, and pigment molecules) content to be 39.9 and 42.28% degraded, respectively (1). Their conclusion was as follows: Standardization of process condition and quality degradation of beetroot juice due to ...


2

The electrons for shuttling are mainly generated in the cytosol from glycolysis. NADH can easily pass the outer membrane, but must be shuttled over the inner membrane. It is important to consider that the electrons must be fed to oxidative phosphorylation from the matrix of the mitochondrion, and not the intermembrane space.


2

I am assuming that your question is: "why can a human intervention improve health?". Let me know if I misunderstood your question. Why can a human intervention improve health? Let's first avoid going into the details of your example. It is quite obvious that human intervention can often improve health in a way that your body alone cannot. To me, an ...


1

The traces you have come from Sanger sequencing. N in genetics means nucleotide (surprising right?). N is used when the base at a given location is unknown (or could be any base pairs). In your case you have Ns because the base-calling software is unable to determine the nucleotide. The first N is due to two peaks overlapping (G and A signals) and the ...


1

So the two Ns that you see are not necessarily variants, but rather likely just poor quality reads. Essentially when you sequence DNA and the sequencer can't make a call as to what the base is, it will just designate it N meaning that the base could be any of the four DNA bases. As for finding the reading from, if you know this sequence contains a stop ...


1

Leukopenia is just a definition. In medicine, there's a saying: Treat the patient, not the numbers. Numbers can mislead people, sometimes quite seriously. Definitions of leukopenia vary: some define it as less than 5,000 WBCs per µL of blood; others define it as less than 4,000. Decreases in specific WBCs is usually described as neutropenia, ...


1

I believe your textbook is referring to the fact that you only perform the complete beta oxidation eight times. Because there's a carboxylic acid at the terminus of a fatty acid chain, the cell takes a slightly different route and reacts it with ATP, which generates a fatty acyl adenylate and pyrophosphate (PPi). This AMP can subsequently be displaced in ...


1

Because all available ATP will likely be quickly spent by various cellular machinery. If there was 20-30mM of ATP, what would stop muscle from contraction and how could you keep ATP level constant at rest, be ready for rapid movement? By blocking all myosin? This creates enormous regulatory problems for the cell. Phosphocreatine buffers energy for a period ...


1

Stress is the reaction, which our body reacts against the pressure or tension. There are many impact of stress on the human body, which includes Emotional: Moodiness, short temper, agitation, inability to relax, feeling lonely and always depressed. Cognitive: Memory problems, unable to concentrate, very poor judgment, negative thoughts, always anxious ...


1

In comments it been discussed that clotting is partial answer to OP. I would say, that is is somewhat tangential to the original question. If I may re-phrase, OP asks: how one can estimate age of blood that has been exposed to air? Problem is that you will have to have a starting point to solve that backwards, like having an initial condition for solving ...


1

I found a nice article that has insights to this matter. As posted before me it is true that only adults, but not juvenile individuals show this difference. Direct and indirect effects of sex hormones on bone marrow erythropoiesis and renal erythropoietin production has been proven, but it works in both sexes the same way. Females are capable to elevate ...



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