Chemoreceptors - heart rate

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  1. ilovemath's Avatar
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    Chemoreceptors - heart rate
    I know blood pH is monitered by chemorepectors in aoritic arch / carotid sinus
    BUT is blood pH also monitered by the medulla?
  2. The Illuminati's Avatar
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    Re: Chemoreceptors - heart rate
    (Original post by ilovemath)
    I know blood pH is monitered by chemorepectors in aoritic arch / carotid sinus
    BUT is blood pH also monitered by the medulla?
    remember the pathway

    receptor(chemoreceptors in the carotid sinus)--->brain (in this case the medulla oblongata)--->effector (the heart).
    The receptors detect the change, an impulse is sent to the medulla oblongata, which sends an impulse either down the accelerator nerve or the vagus nerve (depending on whether pH has increased or decreased) which causes ACh or noradrenaline to be released which bind to receptor sites on the SAN which then causes heart rate to increase or decrease.
  3. ilovemath's Avatar
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    Re: Chemoreceptors - heart rate
    (Original post by The Illuminati)
    remember the pathway

    receptor(chemoreceptors in the carotid sinus)--->brain (in this case the medulla oblongata)--->effector (the heart).
    The receptors detect the change, an impulse is sent to the medulla oblongata, which sends an impulse either down the accelerator nerve or the vagus nerve (depending on whether pH has increased or decreased) which causes ACh or noradrenaline to be released which bind to receptor sites on the SAN which then causes heart rate to increase or decrease.
    well in control of blood temperature the hypothalumus monitors core temperature so I presumed medulla also monitors blood pH....are you saying the latter is incorrect?
  4. The Illuminati's Avatar
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    Re: Chemoreceptors - heart rate
    (Original post by ilovemath)
    well in control of blood temperature the hypothalumus monitors core temperature so I presumed medulla also monitors blood pH....are you saying the latter is incorrect?
    I would say chemoreceptors monitor and the medulla oblongata controls blood pH.
  5. ilovemath's Avatar
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    Re: Chemoreceptors - heart rate
    (Original post by The Illuminati)
    I would say chemoreceptors monitor and the medulla oblongata controls blood pH.
    but with temperature the hypothalumus also monitors, right?
  6. The Illuminati's Avatar
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    Re: Chemoreceptors - heart rate
    Think of monitor as in detection and control as in having the ability to carry out the change. The hypothalamus carries out the change not the detection. Receptors (thermoreceptors or chemoreceptors) monitor/detect. The brain (the hypothalamus, medulla obligate, pituitary gland) control/ carry out the change.
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