Turn on thread page Beta

AQA BIOL1 Biology Unit 1 Exam - 16th May 2011 watch

  • View Poll Results: Are you resitting this unit?
    YES!
    54.92%
    NO!
    45.08%

    Offline

    6
    ReputationRep:
    (Original post by ohhaiikim)
    Can someone explain turberculosis, in a way we would need to answer it in the exam, if asked.

    Also, with the Cardiac Cycle, would we need to mention the Conduction Cycle with it?
    Ok I will just answers a past paper question which was describe the transmission and course of infection of TB

    TB is transmitted via droplet infection and it enters the lungs and lays dormant within the epithelial cells in the form of tubercles after an immune response is stimulated and causes white blood cells to surround the bacteria to prevent it multiplying. This causes tubercles to be placed all around the lung walls, which is scar tissue and causes blood to be coughed up. After a while, the bacteria emerge from the tubercles and being to multiply in turn killing the alveoli and lung cells. This can then spread to other organs e.g. the liver and kill them too.

    Now that was my exact answer and i got 4/5 marked from my teacher without mark scheme so in reality i think it would have got 5
    Offline

    0
    ReputationRep:
    (Original post by sanaindaclub)
    Points to make for TB

    1) Transmitted in droplets/ aerosol
    2) engulfed/ ingested by phagocytes/ macrophages
    3) bacteria encased in wall/ nodule/ tubercle
    4) Bacteria are dormant
    5) If immunosupressed bacteria activate/ released
    6) bacteria destroy alveoli
    7) leads to fibrosis
    8) which leads to increase in diffusion distance/ less diffusion
    9) Activation leads to bacteria entering blood and spreading to other organs

    You wone need all the points!

    Thank you!
    Offline

    6
    ReputationRep:
    (Original post by sanaindaclub)
    Can someone PLEASE PLEASE PLEASE explain cholera, how it works and a five mark answer? I will be forever grateful! I just dont get what the NT book is saying!
    Cholera is caused by a bacteria which attaches to the epithelial cell in the Small intestine and what it does it produce a toxin which binds to the cell membrane of the SI walls cells and inside the epithelial cells and causes chloride ions to move into the lumen of the SI this lowers the water potential inside the lumen and causes water to move out of the surrounding cells and into the lumen thus causing diarrhoea.

    With regards to a treatment, its ORS, how that works is it increase the uptake of Na+ ions/glucose/sugars back into the epithelial cells and creates a lower water potential in the epithelial cells. this then causes water to move back into the cells form the lumen via osmosis thus reducing the effects of diarrhoea
    Offline

    0
    ReputationRep:
    (Original post by reaperguy)
    Ok I will just answers a past paper question which was describe the transmission and course of infection of TB

    TB is transmitted via droplet infection and it enters the lungs and lays dormant within the epithelial cells in the form of tubercles after an immune response is stimulated and causes white blood cells to surround the bacteria to prevent it multiplying. This causes tubercles to be placed all around the lung walls, which is scar tissue and causes blood to be coughed up. After a while, the bacteria emerge from the tubercles and being to multiply in turn killing the alveoli and lung cells. This can then spread to other organs e.g. the liver and kill them too.

    Now that was my exact answer and i got 4/5 marked from my teacher without mark scheme so in reality i think it would have got 5
    ahh okay, thank you!
    Offline

    2
    ReputationRep:
    (Original post by sanaindaclub)
    Points to make for TB

    1) Transmitted in droplets/ aerosol
    2) engulfed/ ingested by phagocytes/ macrophages
    3) bacteria encased in wall/ nodule/ tubercle
    4) Bacteria are dormant
    5) If immunosupressed bacteria activate/ released
    6) bacteria destroy alveoli
    7) leads to fibrosis
    8) which leads to increase in diffusion distance/ less diffusion
    9) Activation leads to bacteria entering blood and spreading to other organs

    You wone need all the points!
    I haven't ever come across the fact that bacteria are dormant or replicates when immunosupressed! I HATE AQA.
    Offline

    0
    ReputationRep:
    please answer my question

    does the elastic tissue in the lungs do the control of air thing
    or the smooth muscle
    what is the difference ?
    Offline

    6
    ReputationRep:
    yeah one of my teachers before each new heading he says. 'the sh*t syllabus version'
    Offline

    14
    ReputationRep:
    (Original post by EffKayy)
    I haven't ever come across the fact that bacteria are dormant or replicates when immunosupressed! I HATE AQA.
    Lol, neither had I! In the jan 2011 paper (my mock) I write all about the transmission and that cows could pass it on and so forth. When i got the mark cheme I was like :eek:

    btw, the answer i gave is from the first five marker from the jan 2011 paper
    Offline

    6
    ReputationRep:
    (Original post by Twilight =D)
    please answer my question

    does the elastic tissue in the lungs do the control of air thing
    or the smooth muscle
    what is the difference ?
    Inhalation uses muscles. The intercostal muscles contract and cause the ribcage to move upwards and outwards. and the muscles in the diaphragm contract and the diaphragm flattens thus increasing the volume of the thorasic cavity and lowering the pressure so air comes in from outside via the pressure gradient

    In exhalation: all the muscles relax and its the natural elastic recoil which reduces the volume and increases the pressure to force the air out
    Offline

    14
    ReputationRep:
    (Original post by Twilight =D)
    please answer my question

    does the elastic tissue in the lungs do the control of air thing
    or the smooth muscle
    what is the difference ?
    The protein elastin in the alveoli wall helps keep it elastic and 'spring back' on exspiration/ exhalation. I know that for emphsema you defo have to mention that elasticity is lost from the alveoli walls and then specifically mention the protein elastin.
    Offline

    2
    ReputationRep:
    (Original post by sanaindaclub)
    Lol, neither had I! In the jan 2011 paper (my mock) I write all about the transmission and that cows could pass it on and so forth. When i got the mark cheme I was like :eek:

    btw, the answer i gave is from the first five marker from the jan 2011 paper
    Yes, I did the jan2011 paper and got a C.
    I got my paper back and got awarded 2/5 and wrote everything from NT book.
    Offline

    14
    ReputationRep:
    And can someone please but info about cholera into 'answer form'
    Offline

    2
    ReputationRep:
    (Original post by reaperguy)
    Inhalation uses muscles. The intercostal muscles contract and cause the lungs to move upwards and outwards.

    In exhalation: its the natural elastic recoil which reduces the volume and increases the pressure to force the air out
    External inter costal muscles, and the ribs move up, not the lungs, also diaphram contracts causing it to flatten.
    Offline

    17
    ReputationRep:
    (Original post by EffKayy)
    I haven't ever come across the fact that bacteria are dormant or replicates when immunosupressed! I HATE AQA.
    Wrong book! The book I'm using explains all of that.
    Offline

    6
    ReputationRep:
    (Original post by EffKayy)
    External inter costal muscles, and the ribs move up, not the lungs, also diaphram contracts causing it to flatten.
    yeah i changed it once i realised what I wrote was not enough
    Offline

    14
    ReputationRep:
    Daft Q but will we get penalised if we spell diarrhoea wrong?
    Offline

    14
    ReputationRep:
    (Original post by swiftylol)
    Wrong book! The book I'm using explains all of that.
    hat book do you use? I use the Nelson thornes one. AQA are supposed to endorse it!
    Offline

    6
    ReputationRep:
    (Original post by sanaindaclub)
    Daft Q but will we get penalised if we spell diarrhoea wrong?
    I know i spelt it wrong in the empa. I am not sure, I think so long as phonetically it is ok it should get the marks..
    Offline

    0
    ReputationRep:
    (Original post by sanaindaclub)
    Daft Q but will we get penalised if we spell diarrhoea wrong?
    No usually not, but diarrhoea is the correct spelling, so remember that
    Offline

    0
    ReputationRep:
    For a Non-reducing sugar test... Do you carry out benedicts test normally to prove that it isnt a reducing sugar and THEN add dilute HCl and Sodium hydrogen carbonate to break into monosaccharides?

    Also do you boil or just heat?
 
 
 
Reply
Submit reply
Turn on thread page Beta
Updated: March 7, 2012

University open days

  • University of East Anglia (UEA)
    Could you inspire the next generation? Find out more about becoming a Secondary teacher with UEA… Postgraduate
    Thu, 18 Oct '18
  • University of Warwick
    Undergraduate Open Days Undergraduate
    Sat, 20 Oct '18
  • University of Sheffield
    Undergraduate Open Days Undergraduate
    Sat, 20 Oct '18
Poll
Who is most responsible for your success at university

The Student Room, Get Revising and Marked by Teachers are trading names of The Student Room Group Ltd.

Register Number: 04666380 (England and Wales), VAT No. 806 8067 22 Registered Office: International House, Queens Road, Brighton, BN1 3XE

Write a reply...
Reply
Hide
Reputation gems: You get these gems as you gain rep from other members for making good contributions and giving helpful advice.