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Today's Mammalian Physiology (OCR) watch

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    (Original post by mc_remedi)
    Can someone please tel me how ruminants such as cows create anaerobic conditions in their stomachs if they swallow air????
    Guh this question bugged me
    I totally guessed and said how ruminants have other chambers such as abomasum, and air just runs through them not effecting the other chamber with the microorganism
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    (Original post by ResidentEvil)
    ****ed u over? that surely wasn't a problem question but just slightly difficult to write 7 points. This was my setup:
    - I first described just a short paragraph about motor neurones releasing neurotransmitter into the neuromuscular junction
    - then it binds to glycoprotein receptors on the sarcolemma
    - sodium channels open, and ions flood in to depolarise
    - action potential is set up along the t-tubules
    - stimulates the muscle cells' sarcoplasmic reticulum to become permeable to calcium ions/calcium channels open
    - ca+ ions rush out from the cisternae
    - diffuses amongst the fibrils
    - therefore muscle contraction
    Ah cool beans then, that's pretty much what I put, just didn't seem like enough at the time.

    I blame my *****y MP book for not giving me enough detail.
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    (Original post by ResidentEvil)
    I totally guessed and said how ruminants have other chambers such as abomasum, and air just runs through them not effecting the other chamber with the microorganism
    I put that the concentration of oxygen would be very low since they're producing tonnes of CO2 and methane and belching all the time, therefore oxygen is unlikely to make it into the second stomach through the sphincter in very high concentration.
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    (Original post by emzie)
    O M G I COULD NOT DO ANY OF THE PAPER. ONLY BIT I COULD DO WERE THE 2 7 MARKERS and i usually get A's theres NO WAY i got over 50%, we hadnt bin taught 90% of what was on the paper, including thr last Q, I F*CKED UP BIG STYLE, no-one at my school could do it, all the questions were WIERD and i revised the whole book and still couldnt do it. im screwed bye bye bye uni like im not even jokin here i was crying at the end of the exam. if only my school let me do the env biology option
    First time i iz using dis, 4 all u people out tere who keep goin on bout wanting to do enviro biology, well guess wat i hated it so much i dropped it 2 teach myself physiology and boy is it hard;

    jus thought id mention that cuz so many peeps wana do envio, so wat dya ppl think of me converting to physiology!
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    Mad!!!
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    i said the conc was low was it would get turned into CO2 and exhalled and the bacteria would use it for resipration and as the stomach was 4-chambered it wouldnt go all the way thru


    and that was one of the better q's - see i told u did ****!
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    The part about cat's eyes was weird :confused: Especially how cats eyes being reflective help them hunt in the dark?!?!? Just said it stops too much light entering and using up all the rodopsin, therefore it reduces the time it takes for dark adaption.

    Also messed yp the motor neruron plate thing, luckly it was only 3 marks. The alzheimers was alright i thought, did anyone talk about standard deviation with the graphs and that the smaller the standard deviation the more reliable the drug was?
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    for cats eyes i said they would reflect the light back out and use it to see. **** i did so SHITE!


    no i didnt talk about that stuf on graph, said that it was fairly const high AB40 so keeps healthy brain, whilst plauqe causing AB42 dropped 80% with a re. low conc.
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    (Original post by MJ_23)
    The part about cat's eyes was weird :confused: Especially how cats eyes being reflective help them hunt in the dark?!?!? Just said it stops too much light entering and using up all the rodopsin, therefore it reduces the time it takes for dark adaption.

    Also messed yp the motor neruron plate thing, luckly it was only 3 marks. The alzheimers was alright i thought, did anyone talk about standard deviation with the graphs and that the smaller the standard deviation the more reliable the drug was?
    The reflective layer means photons that weren't absorbs get reflected so they can be absorbed a again (a second chance for absorbtion so to speak), so you get a higher chance of absorbtion.

    The black spots on the motor neurones were nuclei right? I got the motor neurone plates and the fibres as the other 2.

    I said the drugs resulted in the most reduction in ab42, and least reduction in AB40. It also gave a sharper drop in AB42 so less could be used, and it was more effective in half doses. Also ibuprofen is an analgesic, so side effects.

    And I listed figures
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    [QUOTE=cougem]The reflective layer means photons that weren't absorbs get reflected so they can be absorbed a again (a second chance for absorbtion so to speak), so you get a higher chance of absorbtion.[/quote[

    Yup yup. Maximises available light.

    The black spots on the motor neurones were nuclei right? I got the motor neurone plates and the fibres as the other 2.
    I hope not, I was 99% sure they were mitochondria, since they're the most common organelle in muscle fibres. I put motor end plate and myofibril.

    I said the drugs resulted in the most reduction in ab42, and least reduction in AB40. It also gave a sharper drop in AB42 so less could be used, and it was more effective in half doses. Also ibuprofen is an analgesic, so side effects.
    The bottom one whatever that was the drug of preference right?
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    i thought it was mitochondria too, but muscles are multinucleated so it could be the nucleus. Not a very clear cut question at all.
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    Yeh bottom 1 was drug needed - If that was the Acetylcholine receptor blocker/inhibitor or whatever it was.

    But I think they were nuclei. They were weird shapes for mitochondria, and totally dark staning unlike mitochndria. Also muscle cells are multinucleated as many cells merge to form them.
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    i said the acetylcholine stimutaor - the top one. didnt have a fking clue wot the question was on about. ended up getin the answer - just COMPLETLY the wrong way round.

    I'd never seen that muscle diagram ever in my life!! i said mitochondia but now i kno its nucleus becasue it is a multinucleated cell or wot eva

    i put muscle fibre for the 1st one because the nerve was going onto it.
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    (Original post by cougem)
    Yeh bottom 1 was drug needed - If that was the Acetylcholine receptor blocker/inhibitor or whatever it was.

    But I think they were nuclei. They were weird shapes for mitochondria, and totally dark staning unlike mitochndria. Also muscle cells are multinucleated as many cells merge to form them.
    Oh right sorry, I was referring to the Alzheimer's drugs, but yeah, I put both the bottom drugs as my answer.
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    (Original post by kingpong)
    The reflective layer means photons that weren't absorbs get reflected so they can be absorbed a again (a second chance for absorbtion so to speak), so you get a higher chance of absorbtion.[/quote[

    Yup yup. Maximises available light.
    Hmm surely it is due to the fact that the cats with HUGE pupils let uber large amounts of light in, they get blinded. It's like when people go into have laser eye surgery and they are given drugs to dilate the pupil for the operation. When they come out they have to stay in a dark place for like 12 hours or else their eyesight can get drastically damaged by too much light entering the eye. That is what I wrote, covering your open eyes when it is really bright and staring at the sun (aka beam of light shone in your eyes). Hurts doesn't it. Surely it has to be worth something. The "reflecting light" to help 'em hunt, well I don't see really to be honest. It's not like they have mini torches due to reflection and lets face it if the beam of light is shone in and it is reflected why does the cat need the reflection anyway if there is plenty of light! And I sure as hell have not seen cats eyes reflecting when it is dark?

    Hmm.. Interesting, do you think my point would be worth a mark or two?

    The affect on health withLDLs = coronary heart disease and atheroscelerosis?
    Problem with cholestrol - immiscible in water?

    Regions of brain - picture is from beneath /below.
    Cerebrum
    pituitary I think. (I put hypothalmus d'oh!)
    Cerebellum
    Medulla oblongata.

    When I remember more questions /answers i'll post them up please post if you agree/disagree with answers.

    ---
    What was the deal with the rabbits and the 1st question, re the mucus covering?
    I said to make it into a malteser size snack. (ok I joke :P ) But to stop nutrients leaking out I wrote, and to prevent microorganisms from entering and metabolising it. Wasn't at all sure though.
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    I'm so glad some of you lot thought the paper woz quite nice!! When we came out i woz the only one that hadn't found it a complete nightmare! And me being quite paranoid woz wondering wot id dun wrong! But i'd put quite a lot of the answers the same as you guys!! So cheers for easin my worries!!!
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    i know ive lost at least 12 marks which is depressing; like an idiot i wrote about muscle contraction in the last question; that 3 marks of that diagram i put t tubule dendrite and nucleus (guessed)

    im ****ing depressed theres no way im gna get 68/90 in that

    then the drug i put noradrenaline again this is wrong

    for the cow bacteria wtf??!!! i sed that muscles may be forcing air out and also the bacteria may b submerged in liquid

    for the rabbit **** was the answer to the mucus 1 sumthing 2 do with they can recognise the mucus stuff and its easier 2 swallow?

    the only things i know i did properly was the 1st 7 marker

    ran out of time i was rushing 2 much dno what others think but that was much harder than the january paper (which was more fact based)

    i got thrown off totally in that ******* paper

    ne1 know what the boundaries are likely 2 be?
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    (Original post by Tealer)
    Hmm surely it is due to the fact that the cats with HUGE pupils let uber large amounts of light in, they get blinded. It's like when people go into have laser eye surgery and they are given drugs to dilate the pupil for the operation. When they come out they have to stay in a dark place for like 12 hours or else their eyesight can get drastically damaged by too much light entering the eye. That is what I wrote, covering your open eyes when it is really bright and staring at the sun (aka beam of light shone in your eyes). Hurts doesn't it. Surely it has to be worth something. The "reflecting light" to help 'em hunt, well I don't see really to be honest. It's not like they have mini torches due to reflection and lets face it if the beam of light is shone in and it is reflected why does the cat need the reflection anyway if there is plenty of light! And I sure as hell have not seen cats eyes reflecting when it is dark?
    No, the reflective layer is so light can be absorbed a second time for sure. That argument of yours is useless because the cats can just close their pupils like you or eye in the day time - infact the question even states this was possible.
    The three points (it said 3 marks) were:
    the reflective layer for 2 chanes for absorption
    the pupil can open wide to let much more light in
    3 times as many rod cells which are much more sensitive to dim light

    The affect on health withLDLs = coronary heart disease and atheroscelerosis?
    Problem with cholestrol - immiscible in water?
    Yeh
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    (Original post by goliath)
    for the rabbit **** was the answer to the mucus 1 sumthing 2 do with they can recognise the mucus stuff and its easier 2 swallow?
    I think it was so the bacteria that broke down the cellulose etc could pass through the stomach without being digested as they were covered in protective mucus. Then they could be re-eate them and digest the food which had now been broken down by the bacteria. But that's a guess

    ne1 know what the boundaries are likely 2 be?
    In january they basically upped every1 by a grade, 64 was an A, 54 a B.
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    Not all light is absorbed by rod/cones, therefore whatever light that passes through is reflected back into the eye to possibly be absorped again, I'm pretty sure that's the case, it maximises the use of the light available.

    And I sure as hell have not seen cats eyes reflecting when it is dark?
    Shine a torch at a cat or dog at night and you'll see what I mean. VERY reflective.
 
 
 
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