Biology

If we say a heart attack is the point at which a person begins to experience chest pain, approximately how long the heart muscles is denied oxygen might that be? For the sake of theory, let's assume the artery isn't blocked gradually; it was open, then it's closed.

Not long ago it would seem unthinkable...the Midlands running out of coal. But that's exactly what's happening. Heritage steam railways - which will attract thousands of visitors this May Bank Holiday - are now struggling to find suitable coal supplies in Britain. To keep going, some are having to import coal from thousands of miles away in Russia This is despite the fact that the Midlands sits on millions of tons of coal. Steam railways need the right sort of coal. Locomotives can be damaged if the fuel burns at the wrong temperature, or has too much sulphur or ash content. Different fireboxes and boilers have different requirements. Some railways had been…

Hey This is my first post so i'm not sure if this is the appropriate section to ask this question so please let me know if not. Basically i'm studying medicine and specifically the kidneys currently and have managed to forget lots of my basic school bio knowledge so was hoping someone could help me out. My question is this: what happens if you have a membrane separating 2 solutions of different osmolarities and the membrane is only permeable to solute "X" (not even water). if... solute X is in high concentration on one side relative to the other BUT the osmolarity of the solution on the other side is higher, what happens? Any help is much appreciated.

Hello, I'm a freshman in high-school, and I'm attempting to see if it is possible to harness the abilities of leaves in photosynthesis to create a new power/food source that is more efficient than typical solar panels. I desire to take leaves and either mutate them so that they will grow in all directions to cover a thin sheet (on which they will be given water similar to that used in hydroponics and put out into the sun) or create plant stem cells (if that's even possible) and grow them onto the sheet as leaf cells. I would like to know what the most efficient plant is that you can think of (when it comes to the ability to produce the most glucose in the shortest …

What is the best method for getting an idea of what compounds are contained in a plant extract. hplc is good but it must be followed my mass spectrometry which is far too expensive for me. Tlc is decent but if two compounds have similar rf values it can have errors. Ftir seems to be the only way to go if you want to know all compounds contained within a given mixture. Any recommendations will be helpfull.

from which part flowers produces those fragrances and why ?

Earlier today, my grandma asked me to cut down a grape vine. When I did, I noticed a largeish quantity of sap flowing out. I tasted a drop, and it tasted like water but with a very subtle flavor. Intrigued, I put a glass under it and gathered about a glassful, and drank it. It seemed more refreshing than plain water, with a subtle but interesting taste. So now I'm curious about the composition of grape sap. I'm fairly sure its not poisonous as both grapes and grape leaves are edible, plus I'm not dead. But what sort of things does it have? As for season, the vine did not yet grow its leaves but I suppose would have fairly soon.

I found this spider and its egg cocoon in a bunch of grapes which my Mum bought from the co-op. Unfortunately the spider had been partially crushed by the grapes by the time I found it. I have attached pictures of the spider and the egg cocoon, and would be grateful if anyone could help me to identify it to satisfy my curiousity. (I apologise for the picture quality).

I have been thinking of alternative ways of ridding my house-plants of aphids and it occurred to me that nicotine is a widely used insecticide. Having seen many of the stop-smoking nicotine mouth sprays 'Nicorette Quickmist' on sale in pharmacies, I began to wonder whether, in this form, it would make an effective insecticide mist spray. Any advice/ thoughts on the matter would be welcome.

I was reading this article : http://www.medscape....ticle/777380_10 but quickly became confused where it said "The complexes of anti-IgE bound to IgE are then cleared from the circulation. Thus, activation of allergic responses, at least to small amounts of peanut protein, can be prevented." I was wondering if someone could explain to me how reducing circulating IgE concentrations affect the response for peanut allergy. Since the IgE involved in peanut allergy is bound to mast cells by its Fc region, I was wondering if after allergic reactions mast cell numbers are decreased and hence need to make more peanut specific IgE to present on their cell surface. Can an…

i have seen many insects , mostly house flies , rubbing their hands or legs (whatever it is) but why do they do so ?

when i was cutting some thing with blade , i got a small cut on my finger on palmar surface it started bleeding but after some time it stopped and there was only cut cut not any blood clot so why do we never saw any clot on our palmar surface of hand or leg ? and also then how was bleeding stopped ?

why is our snot is mostly green or yellowish ? i have read about it in many books but i didn't get any reasonable answer , even a book is named on it " why is snot green ? " .

This isnt totally relative to electro magnetism but id like to know if it would be possible to inject a chemical into your body thats able to stick to neurotransmitters and then be activated using some frequency on the electro magnetic spectrum. the chemical itself would probably have to be of some metallic nature or atleast magnetically charged... Im curious as to whether this is physically possible.

Hey guys. Does anyone know what type of sensors are used to determine brain activity? I'm talking about the ones that you often see in TV or online. The sensors connect to the computer and show peaks and activity when a person is thinking about something. Where can I buy these type of sensors? I'm expecting it to be very expensive so is it possible for me to make my own by buying a different type of sensor and modding it? Do the brain sensors measure vibration or electric activity? Thanks for all the help in advance.

why does it feel strange kind of pain when penis get hurt ? (it even dont feel like pain but a strange feeling)

do insects also feel pain ?

http://www.scotsman....longer_1_611507 What do you make of this? I know the idea of regular ejaculation being necessary for good prostate health has become popular despite there not being any hard, conclusive evidence to support it but I'm almost certain that the most recent studies to support this view are misleading or out of context. For example, isn't it possible that men who ejaculate more frequently do so because they have higher levels of testosterone, the higher one's testosterone levels, the lower their DHT (since testosterone-DHT conversion accelerates in middle age and low testosterone/high DHT is associated with prostate cancer, male pattern baldness…

Hi everybody! I'm trying to substitute a 1 Kb promoter, from a bidirectional expression cassette, with another of 644 bp, from another vector. I've tried many times and I've done all the controls (efficiency of ligase, competent cells, restriction enzimes, ecc..): everything work, but every time I've got no colonies!! what could be the problem?? I'm at the first experiences with cloning and I'm desperate thanks to all! alexis

I need scientific evidence that observing a flower and making a statement about the flower only involves the neural networks in the Broca's area and Visual Cortex. I'm new here btw.

Hi everyone ! I would like to know why the sexual dimorphism is reduced when the species are monogamous and important when the species are polygamous ? Many thanks in advance Ps: It's not a homework question but a in case of question exam I realize the anser was on wikipedia after reading carefully... Sorry for the disturbance and for the people interested by the answer: A frequently studied type of sexual dimorphism is body size. Males typically have larger bodies than females. In some species, however, females have larger bodies than males. Sexual dimorphism in body size has been linked to mating behavior. In polygynous species, males compete for cont…

I am a Swedish doctor in medicinal chemistry who is frequently writing articles for scientific journals, particularly in pharmacy. These articles must be written in perfect English. Although my English is good, I am not quite there yet. I therefore need help with proofreading. Is there maybe some student studying pharmacy, medicine, biology or chemistry who would like to earn some extra by helping me out with this? Also, you will get an acknowledgement for your help in the papers which you can refer to as a merit in your CV. If you like writing scientific papers yourself, you can perhaps be a co-author of some paper by participating in the writing later. Please, send …

AGING If anyone has read Ending Aging by Aubrey de Grey, you'll immediately see that he takes a sort of engineering perspective to stopping aging which I agree is a much better than "messing with the complex genetic pathways of our body" but I've taken his idea is little further by trying to further remove what I don't think is a necessary practice. Please tell me what you think about my summary of my hypothesis. "We age because homeostasis is lost. There is an abnormal balance of chemicals which leads to an abnormal expression of genes. That is obvious. What is less obvious is what causes many of these disorders. I’ve determined that many of the seemingly und…

Hi everyone, I was reading a paper, and I found the term "assortative mating". It's a synonym of homogamy or there is a difference between these terms ? Thanks in advance for your help

I want to know how much animals are like us. Like humans, do animals also have irises of various colours? Do their eyes accomodate and function the same way? It all is always being taught about humans, but to what extent are animals like us in their vision and eyes?