1. Dismiss Notice
  2. Download free Tapatalk for iPhone or Tapatalk for Android for your phone and follow the SDN forums with push notifications.
    Dismiss Notice

biochemistry decks question

Discussion in 'NBDE Exams & Licensure Exams' started by econservative, May 9, 2008.

  1. econservative

    2+ Year Member

    Joined:
    Feb 20, 2008
    Messages:
    127
    Likes Received:
    0
    Status:
    Dental Student
    Which of the following components of the electron transport chain only accepts electrons

    A. FMN
    B. Coenzyme Q( ubiquinone)
    C. cyrochrome b
    D. oxygen

    please explain the answer as according to me it is the complex-2 which only accepts eletrons and doesnot transport hydrogen ions
    :confused:
     
  2. Note: SDN Members do not see this ad.

  3. impaction

    2+ Year Member

    Joined:
    Mar 26, 2008
    Messages:
    207
    Likes Received:
    0
    Status:
    Dental Student
    for me the question looks incomplete,
    as A B C all accept electrons and oxygen is not a part of the chain,,:idea:
     
  4. econservative

    2+ Year Member

    Joined:
    Feb 20, 2008
    Messages:
    127
    Likes Received:
    0
    Status:
    Dental Student
    this is the dental decks question( straight away given in dental decks as a main quetion) as it is copied from there and it in the topics of enzymes in dental decks :mad:
     
  5. I'mFillingFine

    I'mFillingFine Pulptastic
    5+ Year Member

    Joined:
    Jul 23, 2005
    Messages:
    3,530
    Likes Received:
    3
    Status:
    Dental Student
    I agree that if complex 2 had been a choice, that'd be it. Perhaps in this case they want you to say O2 because it does nothing besides accept those terminal electrons. Is that what the card says is the answer?
     
  6. Ibanez

    Ibanez Hai Ya!
    2+ Year Member

    Joined:
    Aug 12, 2007
    Messages:
    213
    Likes Received:
    3
    Status:
    Dental Student
    Cyt. b

    • NADH gives out HYDRIDE ion, and not an electron, to Complex 1. The e- is transported further and the hydrogen is taken up by FMN and is reduced to FMNH2. Option 1 is invalid.
    • O2 ACCEPTS Hydrogen; THE BY-PRODUCT is WATER in oxidative phosphorylation. Option 4 is invalid.
    • And no ETC complex is intimately related to H+ pumps, it is ONLY because of the gradient that is created with the transport of e- and NOT BECAUSE OF THE PARTICIPATION of H+ in ETC. It plays a passive role. And is hypothetical, though widely accepted (but not yet proved!)
    • UBIQUINONE accepts the hydrogen from FMNH2 and is REDUCED. (FMNH2-->FMN + H2)
    • Cyt b accepts ELECTRON from ubiquinone. (The previously reduced ubiquinone is oxidized back to Q; and the H+ from Ubiquinone adds to the gradient and is transported to mitochondrial matrix where it reacts with O2 to form H2O)
    I've answered this to "almost" best of my ability... (Damn I need some sleep!)

    Mayank.

    PS *Sprechgesang* I want my MTV, uh no I meant my Nobel Prize. I want my Noble Prize.:rolleyes:
     
  7. econservative

    2+ Year Member

    Joined:
    Feb 20, 2008
    Messages:
    127
    Likes Received:
    0
    Status:
    Dental Student
    thanxs a lot Ibanez for explaning this answer in detail



    Cyt. b

    • NADH gives out HYDRIDE ion, and not an electron, to Complex 1. The e- is transported further and the hydrogen is taken up by FMN and is reduced to FMNH2. Option 1 is invalid.
    • O2 ACCEPTS Hydrogen; THE BY-PRODUCT is WATER in oxidative phosphorylation. Option 4 is invalid.
    • And no ETC complex is intimately related to H+ pumps, it is ONLY because of the gradient that is created with the transport of e- and NOT BECAUSE OF THE PARTICIPATION of H+ in ETC. It plays a passive role. And is hypothetical, though widely accepted (but not yet proved!)
    • UBIQUINONE accepts the hydrogen from FMNH2 and is REDUCED. (FMNH2-->FMN + H2)
    • Cyt b accepts ELECTRON from ubiquinone. (The previously reduced ubiquinone is oxidized back to Q; and the H+ from Ubiquinone adds to the gradient and is transported to mitochondrial matrix where it reacts with O2 to form H2O)
    I've answered this to "almost" best of my ability... (Damn I need some sleep!)

    Mayank.

    PS *Sprechgesang* I want my MTV, uh no I meant my Nobel Prize. I want my Noble Prize.:rolleyes:[/quote]
     
  8. Ibanez

    Ibanez Hai Ya!
    2+ Year Member

    Joined:
    Aug 12, 2007
    Messages:
    213
    Likes Received:
    3
    Status:
    Dental Student
    You're welcome! By the way I'm Mayank (Ibanez is the silly guitar brand I own and despise :eek:)

    Mayank.

    PS I wish I could change my screen-name.
    PSS I don't own the brand, I just have one piece.
     
  9. impaction

    2+ Year Member

    Joined:
    Mar 26, 2008
    Messages:
    207
    Likes Received:
    0
    Status:
    Dental Student
    keep hopes dude, you can own it one day

     
  10. Ibanez

    Ibanez Hai Ya!
    2+ Year Member

    Joined:
    Aug 12, 2007
    Messages:
    213
    Likes Received:
    3
    Status:
    Dental Student
    I'll own Les Paul or Gibson if given a chance, but "Ibanez" can suffer... :laugh:

    My hope is cold, my faith is gone!
    25 days till death (thanks to NBDE Part 1) do me apart... :p
    I've lost count of the days remaining for my exam, maybe "28" and not 25? :laugh:

    Mayank.
     
  11. simkarl

    2+ Year Member

    Joined:
    Sep 25, 2007
    Messages:
    47
    Likes Received:
    0
    Status:
    Dentist
    hey The Lord of Tragedy thanks for explanation and worm up and count down.. and .cheer up ..
     

Share This Page