POPULATIONS IN ECOSYSTEMS - AQA A LEVEL BIOLOGY + EXAM QUESTIONS RUN THROUGH

In this video, I explain ALL of the content required for the "Populations in Ecosystems" section for AQA A Level Biology. This includes: key definitions, effect of abiotic factors, interspecific + intraspecific competition, predation, estimating population size (quadrats, transects + mark-release recapture), primary succession and conservation of habitats by managing succession. Time stamps are in the comments.
I also go through a few exam questions and explain their mark schemes.
The content in this video crosses over with other exam boards too.
Please leave a comment if you have any questions, I'll be more than happy to answer them!!! :)

[@AlevelBiologyHelp]

00:57 = Important definitions
02:23 = How abiotic factors affect population size
03:27 = Interspecific competition
04:33 = Intraspecific competition
05:42 = Predation
08:15 = Estimating population size: quadrats
09:53 = Estimating population size : belt transects
10:54 = Ways of estimating population size using a quadrat
11:42 = Mark-release-recapture
14:21 = Primary succession
17:18 = Conservation of habitats
18:58 = Exam questions and mark schemes

[@spine747]

thank you so much! I am WJEC so I hope this helps :)

[@cdpworkouts7518]

i did not expect your videos to be this helpful but they are, thank you.

[@phoenixraven2779]

Thanks for this, it's amazing :)

[@seokjinkim9604]

Thank you so much! I just got an A for A-level biology

[@AlevelBiologyHelp]

Wow well done you!

[@seokjinkim9604]

@@AlevelBiologyHelp thanks! it was very helpful. can I ask if you are also planning to do videos on A-level chemistry?

[@eems4565]

oh my god did u get the A for the actual exam or for mocks ?? anyway,, congrats !! ♡♡ any study tips for a fellow student in need 😭☝️

[@seokjinkim9604]

@@eems4565 All I did was to make study notes from videos on this channel, and then did a lot of past papers like 2 weeks before the exam. I didnt even use textbooks since it had too much useless info that wont even come up in exam lol

[@daniellucas3907]

Thankyou so much!!!

[@pianosnotacrime8891]

Thank you! Very helpful

[@margotc2780]

this makes me wanna throw up & cry

[@multuralcarxism1570]

real

[@qasimkhan34]

damn gurl i can make u cry and throw up

[@lovelyactivityclasses3031]

Awesome

[@lizzy2804]

this was amazing

[@RAHMANISHMIL]

Hi, miss does your lesson content hit all the specifications point in the AQA spec. i just want to confirm so that i don't want to learn things that I might not be assessed on if you get what I mean.

[@AlevelBiologyHelp]

Yes, this hits all the specification points :)

[@gracekaye3319]

Do we need to know about secondary succession, I believe it wasn’t covered in the video

[@AlevelBiologyHelp]

It'd not in the specification, so no!

[@danghali9041]

legend

[@redainaafridi4133]

Hello, thank you for the video,
I’m just a bit confused with the question on how assumptions made on the proportional sampling differ from MRR. I thought you said that in MRR (or in the kerboodle textbook) it says that with MRR you can make the assumptions that your marked sample was thoroughly distributed. But you have wrote that that isn’t an assumption with MRR so I’m a bit confused.

[@AlevelBiologyHelp]

Hi! I wasn't supposed to say in the video that the assumption is that they have time to distribute evenly, woops! The assumption is just that they have enough time to distribute, but not necessarily evenly i.e. there could be more organisms in one area of a field. So there is no assumption that organisms distribute themselves evenly, if that makes sense?

[@jasmin4518]

3:47 its a leopard :)

[@AlevelBiologyHelp]

Haha ok thank you, I clearly need to brush up on my big cat knowledge!