RESPIRATION - AQA A LEVEL BIOLOGY + EXAM QUESTION RUN THROUGH

In this video, I explain ALL of the content required for the "Respiration" section of AQA A Level Biology. This includes: glycolysis, link reaction, Krebs cycle and oxidative phosphorylation. Time stamps are in the comments section. The content in this video crosses over with other exam boards too!
I also go through a few exam questions and explain the mark schemes.
Please comment if you have any questions, I'll be more than happy to answer them!! :)

Пікірлер: 51

  • @seokjinkim9604
    @seokjinkim96042 жыл бұрын

    also, the triose phosphate produced by the phosphorylation of glycerol, wouldn't it enter glycolysis and not Krebs cycle?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Yes you're right - it would enter glycolysis!!!!! I'll pin this comment

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Such a stupid error - sorry about that. Even I get things wrong sometimes! 😭

  • @yaz0318

    @yaz0318

    Жыл бұрын

    @@AlevelBiologyHelp then does this mean the carbon compound also enters glycolysis ?

  • @AlevelBiologyHelp
    @AlevelBiologyHelp3 жыл бұрын

    00:52 = Glycolysis 03:50 = Anaerobic respiration (fermentation) 04:52 = Link reaction + Krebs Cycle 10:17 = Lipids and amino acids can be used in respiration 11:24 = Oxidative Phosphorylation 15:06 = Exam questions and mark schemes

  • @erinstewart2984
    @erinstewart2984 Жыл бұрын

    Watching these videos hours before my end of topic tests and still getting As is a blessing

  • @goldielocks9092
    @goldielocks90923 жыл бұрын

    Thank you so much for this video. My book complicates everything so much, this video was extremely easy to understand and I understand the topic really well right now thanks to you!

  • @taylorprice1440
    @taylorprice14402 жыл бұрын

    this is unbelievably helpful. i’m failing miserably at the moment. i really feel much better for my test this afternoon. thank you!

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Aw thank you! Best of luck in your test, let me know how it goes!

  • @SH-bt3rw
    @SH-bt3rw3 жыл бұрын

    Thank you so much for this video! It was really helpful :)

  • @scitastic720
    @scitastic7202 жыл бұрын

    Tysmmmmm💕💕💕💕 you are a blessing

  • @tanyaakthar9338
    @tanyaakthar9338 Жыл бұрын

    Great video 👍

  • @jasminei4382
    @jasminei43822 жыл бұрын

    I’m struggling to understand this chapter but this has helped thank you :)

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    It is very difficult! Glad I could help. :)

  • @dikiajoshua4586
    @dikiajoshua4586 Жыл бұрын

    Amazing explanations

  • @mera9679
    @mera96792 жыл бұрын

    Thank you for including the exam questions - i have an exam in 10 minutes and this helped me out very much!

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    How did the exam go?

  • @lydiazanetti
    @lydiazanetti2 жыл бұрын

    your videos help me a lot thank you for making them

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    You're so welcome!

  • @bk250
    @bk2502 жыл бұрын

    this video was great and helped me to get an A

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Massive congratulations! Well done x

  • @Farah-dc4bb
    @Farah-dc4bb3 жыл бұрын

    Why does the volume remain constant in the question at 25:28 ? Surely the same amount of oxygen wouldn't be taken up since one is aerobic and one is anaerobic?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    Hi! The mark scheme is quite confusing for this one, but what it's saying is that because the yeast is now respiring aerobically, the volume of oxygen taken up and the volume of carbon dioxide is now equivalent so the total volume of gas in the syringe remains the same. I hope this makes sense :)

  • @imogennnnn
    @imogennnnn3 жыл бұрын

    I thought NADP was reduced NAD, but the video stated that glycolysis produced 2x NADH. Does that mean NADP and NADH are the same? I though NADH was just normal NAD?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    Hi! NADP and NADH are not the same. NADP (used mainly in photosynthesis) is NAD with a phosphate attached to it. NADH is reduced NAD (hence the extra hydrogen suggesting a reduction). Hope this makes sense :)

  • @imogennnnn

    @imogennnnn

    3 жыл бұрын

    @@AlevelBiologyHelp thank you! That helps a lot. I tried to find the answer online but it wasn't as clear!

  • @cait3
    @cait33 жыл бұрын

    for oxidative phosphorylation- would it not be 2NADH that is used?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    Technically, 10NADH are used in oxidative phosphorylation, but at A level, you don't really have to know the exact numbers, just that NADH is used. It's good to know though 😁

  • @cait3

    @cait3

    3 жыл бұрын

    @@AlevelBiologyHelp 10NADH?? damn.

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    @@cait3 Yep! Two from glycolysis, two from the link reaction, and six from the Krebs cycle!!

  • @seokjinkim9604
    @seokjinkim96042 жыл бұрын

    hello, can I ask if you need to know how many carbon atoms that each molecule contains? e.g. pyruvate (3C), thus 3 carbon atoms thanks :)

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Yes you need to know that as it helps you to understand what is happening in the process :)

  • @seokjinkim9604

    @seokjinkim9604

    2 жыл бұрын

    @@AlevelBiologyHelp thanks :)

  • @hillaryantwi9279
    @hillaryantwi92793 жыл бұрын

    When did you do your A levels?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    June 2019 :) so a couple of years ago

  • @emmafive2647
    @emmafive26472 жыл бұрын

    Is this everything we need to know on the spec or are there any gaps ❣️

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Hi, this is everything you need to know!

  • @hoau1406
    @hoau1406 Жыл бұрын

    5:23

  • @nilakshipravin989
    @nilakshipravin989 Жыл бұрын

    why link reaction and krebs cycle can't happen without oxygen?

  • @dominikprajzner2335

    @dominikprajzner2335

    Жыл бұрын

    Oxygen is the terminal electron acceptor in the electron transport chain, if the electrons aren’t taken up because there’s no oxygen then NADH and FADH2 can’t be oxidised and release their electrons

  • @jasmin4518
    @jasmin45182 жыл бұрын

    at 4:59 is that meant to be the link reaction?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Yes

  • @hoau1406
    @hoau1406 Жыл бұрын

    10:11

  • @safandsound
    @safandsound3 жыл бұрын

    How come you didn't mention Hexose biphosphate?

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    Hi! I'm assuming you're on about glycolysis? For AQA, you don't need to know it in much detail at all (look at the specification). You just need to know that glucose is phosphorylated and is split into triose phosphate

  • @safandsound

    @safandsound

    3 жыл бұрын

    @@AlevelBiologyHelp We had to know it was formed, and that it splits into the two triose phosphate molecules, but that was about it. Thanks for replying!

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    3 жыл бұрын

    @@safandsound Yes I think it's better to learn it in a bit more detail than what the specification states to improve understanding :)

  • @bestbest1785
    @bestbest17852 жыл бұрын

    im in year 12, biology is easy for now but this is looking like a nightmare

  • @frog2098

    @frog2098

    2 жыл бұрын

    This and respiration have probably been the worst so far

  • @nojams1807
    @nojams18072 жыл бұрын

    YOU HAVE TOO MANY ADS

  • @AlevelBiologyHelp

    @AlevelBiologyHelp

    2 жыл бұрын

    Aw I'm sorry! I'm currently trying to go through my videos and reduce the number of ads :)