Hey there! Sign in to join this conversationNew here? Join for free
    Offline

    0
    ReputationRep:
    Hey guys,
    I'm getting confused with all the stuff abotu exercise and control of the heart rate and ventilation rate stuff..

    Could some please explain to me the steps that follow once someone starts exercise with respect to the heart rate increasing and ventilation rate increasing etc..

    Thank you so much
    Offline

    0
    ReputationRep:
    (Original post by dynamikal)
    Yeah dont worry my exam is still the same as you guys :P
    Although I start 15 minutes earlier than you Mos001.

    But yea doughy's got it :P I have chem on 28th ;(

    HURRY UPPPP.

    On a biology note, can someone explain the structure of rod and cone cells to their functions? My CGP book explains what they do but no so much on the structures, and ive seen a past paper q or two with arrows pointing so a certain feature and asking whats this and im like ZOMG ROD.
    SAME HERE! CAN'T WAIT FOR IT TO BE OVER!!! :eek3:
    Offline

    1
    ReputationRep:
    I want this exam to be tomorrow morning. I am so ready for it now I just don't want to wait until Friday in case I forget something
    Offline

    0
    ReputationRep:
    (Original post by Mr van der WAALs)
    I want this exam to be tomorrow morning. I am so ready for it now I just don't want to wait until Friday in case I forget something
    wow, :eek:
    Offline

    0
    ReputationRep:
    (Original post by Mr van der WAALs)
    I want this exam to be tomorrow morning. I am so ready for it now I just don't want to wait until Friday in case I forget something
    That's exactly how I feel! But we are probably being too paranoid :yep:
    Offline

    0
    ReputationRep:
    i'm gonna hammer biology revision after pe exam tomorrow...well thats the plan :rolleyes:
    • Thread Starter
    Offline

    9
    ReputationRep:
    I am definitely not ready for this!!!

    Pain and gender section of the article is total crap. I don't understand it V_V
    Offline

    0
    ReputationRep:
    (Original post by Shining*)
    Hey guys,
    I'm getting confused with all the stuff abotu exercise and control of the heart rate and ventilation rate stuff..

    Could some please explain to me the steps that follow once someone starts exercise with respect to the heart rate increasing and ventilation rate increasing etc..

    Thank you so much
    Well...

    When you start exercising you're respiring more and there's a greater concentration on CO2 in the blood - this decreases the pH of the blood. Chemoreceptors detect a decrease in pH and send nerve impulses to the medulla (the part of the brain responsible for controlling breathing rate), which then sends more frequent nerve impulses to the intercostal muscles and diaphragm, which increases the rate and depth of breathing.

    And ventilation rate increases due to the rate and depth of breathing increasing - there's a greater volume of air being breathed in and out over a period of time.

    Hope that helps / makes sense, don't know if you want it in any more detail :p:
    • Thread Starter
    Offline

    9
    ReputationRep:
    What about stretch receptors?
    Offline

    0
    ReputationRep:
    (Original post by dynamikal)
    Yeah dont worry my exam is still the same as you guys :P
    Although I start 15 minutes earlier than you Mos001.

    But yea doughy's got it :P I have chem on 28th ;(

    HURRY UPPPP.

    On a biology note, can someone explain the structure of rod and cone cells to their functions? My CGP book explains what they do but no so much on the structures, and ive seen a past paper q or two with arrows pointing so a certain feature and asking whats this and im like ZOMG ROD.
    I saw this on a past paper and didn't have a clue either, found this with the structures on though http://en.wikipedia.org/wiki/File:Cone2.svg

    But I haven't revised this section yet so I'm not sure about their functions!
    Offline

    0
    ReputationRep:
    (Original post by Doughboy)
    What about stretch receptors?
    Yeah and them >_> Forgot to say about them, he/she just asked about how excercise increases breathing rate so i only really thought about blood pH and chemoreceptors and such.

    I'm gonna revise a bit more. :p:
    Offline

    0
    ReputationRep:
    The green student book says,
    Deoxyhaemoglobin absorbs the radiowave signal and later re-emits it, while oxyhaemoglobin does not. When an area of the brain is active, the blood flow to that area increases and more oxyhaemoglobin is delivered to supply the active cells with the oxygen they need from aerobic respiration. Less of the signal is absorbed as a result.

    But, isn't amount of deoxyhaemoglobin increases when oxyhaemoglobin is more...and so shouldn't more of the signal be absorbed when the brain is active?

    (Original post by shuvo_roy)
    I havent got my answer and think it felt too back in the thread..and so posted it again!.......someone please help!
    i don thk i can answer your question though. can someone help pls? bt i don understand y would amount of deoxyhaemoglobin increase when oxyhaemoglobin increase?
    Offline

    0
    ReputationRep:
    Cheers Live Laugh Love!
    Offline

    0
    ReputationRep:
    So hard to memorise some of this stuff.
    Offline

    4
    ReputationRep:
    I still need to cover topic 8 in more depth and the article.. :facepalm2:
    Offline

    0
    ReputationRep:
    fml. s*** day of revision for me.
    waking up at 6. and cracking on.
    got some examiner dude coming into college tomorrow to help us. will put up any useful stuff here. (Y)
    night lads and ladettes.
    Offline

    0
    ReputationRep:
    (Original post by Doughboy)
    What about stretch receptors?
    Beginning of exercise --> more blood returns to heart (due to contractions of muscles in legs/arms) --> more blood flows into atria --> receptors stretched more --> nerve impulses to cardiovascular centre increases --> nerve impulses back through sympathetic nerves --> SAN stimulated --> heart rate increases..

    There we go.
    Offline

    0
    ReputationRep:
    Does anyone know where the mark scheme to the June 2009 unit 5 paper is? Cos it doesn't seem to be on the Edexcel website? Thanks
    Offline

    0
    ReputationRep:
    I'm willing to link some concise notes on neurons and the eye if anyone wants them..

    They don't contain diagrams on neurons and rods though.. I drew them after I printed them..
    Offline

    0
    ReputationRep:
    (Original post by HyperNova)
    I'm willing to link some concise notes on neurons and the eye if anyone wants them..

    They don't contain diagrams on neurons and rods though.. I drew them after I printed them..
    If you're willing to share go for it man. Concise sounds good
 
 
 
Poll
Do you agree with the PM's proposal to cut tuition fees for some courses?

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.