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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 + ...


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 ...


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 ...


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 ...


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 ...


0

On average, it has been stated to be about five weeks however it differs from person to person based primarily on physical stats. The process that would occur : First food that remains in your stomach is digested Readily available energy is then absorbed (This includes glucose, carbohydrates, anything that generally doesn't mean fat) Your body then begins ...


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, ...


0

I know WBC is primarily responsible for fighting infectious micro-organisms, but does it have any significant role in cleaning up body's own malfunctioning or ageing cells? They kill the pathogens, infected, senescent, mutated or unnecessary cells, clean up the cell fragments, clean up the oxidized LDL from the surface or arteries, etc... So I think ...


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 ...


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 ...


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 ...


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 ...


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), ...


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.


1

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 ...


0

This wiki article describes in some detail relationship between molecular composition of hair and colour name http://en.wikipedia.org/wiki/Human_hair_color Hair with highest content of pheomelanin seems to be called red (moslty pheomelanin) or auburn (less pheomelanin)


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 ...


0

The changes in image size in myopic eyes are not as large as one would imagine. In fact, they are pretty close and the myops are probably not aware of them until the proper correction is placed which affect the image size in a much greater degree. You can see on the image that the sizes of retinal images are very similar - the uncorrected image size is ...


7

When you travel to different time zones, your circadian clock will be off. 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 huge ...


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


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 ...


0

Sleep occurs in stages. There are three stages of non-REM sleep followed by REM sleep. Natural waking occurs during the REM stage. If your alarm goes off while you are in the middle of deep sleep, you are going to feel different from if you had woken up naturally. That's why there's a market for alarm clocks designed to wake you up during light sleep.


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 ...


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 ...


0

Memories are not stored in just one part of the brain. They are widely distributed throughout the cortex and neurons. The long-term memories are stored throughout the brain as groups of neurons, the brain stores memories in three ways--Short-term memories, Sensory memory and Long-term memory the human brain cell can hold 5 times as much of information as ...


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 ...


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 ...


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 ...


0

I have to challenge both ideas. First, I learned to swim without any instruction, basically from being pushed into the deep part of the creek by the bigger kids. Of course I got better with practice, but I've never had any sort of formal instruction. Second, not all animals can swim. I have two dogs: one swims like a seal (and has since I got him at ...


0

found on internet: After blood donation, it generally takes a day or two to replenish the fluid volume in the body and three months for the regeneration of red cells to donate more blood. The total amount of blood circulating in our body's cardiovascular system is about 5 liters. Of this amount, only about 350 ml. is bled from the body during blood ...


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

My answer below directly (and solely) addresses what I think is the main gist of the question: Are there any adverse effects on one's physiology as a direct result of donating blood? Blood donation, at the amounts typically taken (200~500mls), will not harm you. A healthy human being produces approximately 100,000,000,000 (one hundred billion) NEW ...


4

You might need to narrow your parameters a bit. Just things to consider: Our lungs are not hollow organs that can accommodate an oxygen producing machine. They are basically narrow tubes that get smaller and smaller until they end in a tiny balloon-like structure - about 700 million of them. Where would the machine go? 100% oxygen is toxic to the lungs, ...


1

Actually, hyperthermia is a known treatment for a range of diseases, including cancer. Induced hyperthermia can be whole-body as well as local/regional and is under investigation in multiple studies (for example).


7

Parent 1 and 2 have each 5 possible genotypes (OO, AO, BB, BO and AB). Here a Punnett square with each possibilities. I highlighted the possible parent genotypes. The total number of possible crosses is exactly 21. Note that here A = Ia, B = Ib and O = i. OOxBB,OOxBO,OOxAB AOxBB,AOxBO,AOxAB BBxOO,BBxAO,BBxBB,BBxBO,BBxAB BOxOO,BOxBB,BOxAO,BOxBO,BOxAB ...


-1

Yawning increases pressure in eustachian tube because it takes place during inspiratory phase of respiration, so pushes Ear drum on the outer side


1

The two main chemical processes in the human body that generate carbon dioxide (CO2) are: Basal metabolic process of CO2 (CO2m) produced by the combustion of sugar in organs and tissues of the body. Bacterial decay processes occurring as a result of activity of the microbial fauna in the colon. This forms CO2 (CO2c), H2, CH4 and higher hydrocarbons, NH3, ...


0

The organism as a thermodynamic machine does need a coolant. The more difference in temperature the more efficiently thermal machine can use energy. Also in all processes in organism it is produced excessive thermal energy, which should be removed. Thus colder water and air are pleasant.


4

Short answer: Cold is pleasant only when your are not already freezing and cold might satiate thirst better because it acts as enhancer of the "water intake flow meter". Is cold water more tasty than warm water? No, it is actually the reverse as detailed in my footnote. Cold is pleasant when your body is over-heating and definitely not if you live naked ...


6

The muscle spindle normally stretches/contracts in concert with the muscle fibres in order to maintain detection of changes in length. This image should demonstrate it clearly: When the muscle spindle is stretched and excited it sends impulses to the spinal cord more rapidly (increased frequency). The sensory neurons synapse with alpha motor neurons ...


2

In addition to cultural preferences and psychological factors, there may be some evolutionary basis in this. Cooking food is a relatively new development and unique to the Homo spp. line. It makes sense that the tongue/mouth may be more sensitive to cooler temperatures than warm temperatures, given the amount of actual exposure it is given to sunlight ...


-1

I think our body welcomes cool fluid as it likes to cool it self down. A person who is about to die from cold will never prefer a cool drink however in the same temperature if the person is comfortable he will chose a cool drink then again to cool his body as the body comparatively feels warmer.



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