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  1. #1
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    Question Heat stable toxin

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    If soil is heated at 100 degrees celsius for 20 minutes, which will still be alive?

    A) B. anthrax
    B) Botulinum toxin
    C) Smallpox virus

    Please explain your answer.

  2. #2
    bckwood's Avatar
    bckwood is offline Senior Member 510 points
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    B) Botulinum toxin, toxins are readily destroyed by heat, and cooking food at 80C for 30 min safeguards against botulism. C. botulinum spores are highly heat-resistant and may survive boiling for several hours at 100C, exposure to moist heat at 120C for 30 min will kill the spores. By not destroying the spores toxin production can resume at a temp as low as 4C.

    Thats my guess.....

  3. #3
    Goldspot6 is offline Newbie 510 points
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    also, consider what the question is asking... B. anthracis is zoonotic and thus would NOT be found in soil... but bckwood's answer is also correct.. the key is that if not properly heated, the spores survive and once they are put into an anearobic environment, the spores mature and sythesize a neurotoxin

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    Goldspot6 is offline Newbie 510 points
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    actually im gonna go ahead and change my answer... i dont think any of those will be the answer, well at least according to Kaplan... which says that clostridium has a HEAT LABILE toxin that is killed after 10 minutes at 60 C... so my answer would be staph.. or B. cereus.. something that is heat stable... although staph isnt found in soil... but kaplan actually does say that B. cereus spores are "widely found in nature" so i wouldnt rule out being found in soil..

  5. #5
    bckwood's Avatar
    bckwood is offline Senior Member 510 points
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    Quote Originally Posted by Goldspot6
    also, consider what the question is asking... B. anthracis is zoonotic and thus would NOT be found in soil...
    yes, but the spores can be shed and live for months or even years in the soil........

    http://64.233.179.104/search?q=cache...s&ct=clnk&cd=1

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    blrman76 is offline Newbie 510 points
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    Cool

    Quote Originally Posted by Unregistered
    If soil is heated at 100 degrees celsius for 20 minutes, which will still be alive?

    A) B. anthrax
    B) Botulinum toxin
    C) Smallpox virus

    Please explain your answer.
    In my opinion answer is A

    Bacillus anthrax spores will be alive even if soil is heated to 100 degrees celsius.

  7. #7
    lira99's Avatar
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    I am agree the answer it is A
    because the spores are heat resistant, even they are used to test heat sterilization procedures
    Last edited by lira99; 04-25-2006 at 03:43 AM.

  8. #8
    sarda is offline Member 510 points
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    B but not sure

  9. #9
    MDiva's Avatar
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    I choose A for the same reason as the others.
    I used to pray and pray for a bike and never got one. Later I learned that God doesn't work that way... so I went out and stole a bike and asked God for forgiveness.

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