GAS EXCHANGE- AQA A LEVEL BIOLOGY + EXAM QUESTION RUN THROUGH

All of the content required for the Gas Exchange section for AQA A Level Biology. This includes: surface area to volume ration, single-celled organisms, gas exchange in insect, xerophytic plants and humans. Also, I go through a couple of exam questions and their mark schemes. Please comment if you have any questions! :)

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[AlevelBiologyHelp]

00:24 = Surface area to volume ratio
01:19= Fick's law
01:43 = Gas exchange in single-celled organisms
02:14 = Gas exchange in INSECTS
04:35= Gas exchange in FISH and the counter-current exchange principle
07:31 = Gas exchange in xerophytic/dicotyledonous plants
09:11= Gas exchange in HUMANS and the mechanism of breathing
12:46 = Exam questions and mark schemes

[AlevelBiologyHelp]

Hi everyone, I didn't mention different lung diseases because you technically don't need to learn about them for the exam, you just need to apply the knowledge from the video into data associated with different lung diseases. The cause/effect of the disease will be stated in the stem of the question usually.

[mihininja]

I've got the AS exams in two days and am using this for some nice last minute revision. Pray for me-

[wtfclipz]

(sorry this is just to make my revision easier)
00:24 = Surface area to volume ratio
01:19= Fick's law
01:43 = Gas exchange in single-celled organisms
02:14 = Gas exchange in INSECTS
07:31 = Gas exchange in xerophytic/dicotyledonous plants

[sonadent]

13:57 you used the answer from the stem of the question, that means when they ask you how did they etc etc you need to look back at the context

[Lavin.]

05:59 states that one of the adaptations for gas exchange in fish is that the filaments are thin increasing the rate of diffusion. doesnt the rate of diffusion decrease becuase that is what I saw in the mark scheme???

[shamailakhan]

How do you know the answers so specifically I struggle with this and end up writing too much

[courtneyxo]

I have an exam in a few weeks on this I don't know if I should be making notes or if I should do practice questions and learn the content through that way. by looking at the mark scheme memorising the answers. what would you say is better ?

[Yoemono_]

hello,
is this everything you need to know for exams, also do you thibk I have time to go through all of AS content in 2 weeks and 2 days,
not sure if I could

[Zehraaaa]

at 9:10 you mentioned that the cuticle rolls to cover stomata snd how that lowers the water potential gradient and less water is lost by evaporation and you explain how the rolling of the cuticle lowers the water potenial. ps your videos are a life saver

[AmiraMohamed-zozt]

at 1:19 when you mention ficks law I've never come across it so im a bit confused on whether we need to know it or not :)

[taqwakhan]

lol i have a test tommorow and havent revised