CONTROL OF HEART RATE - AQA A LEVEL BIOLOGY + EXAM QUESTIONS RUN THROUGH

In this video, I explain ALL of the content required for the "Control of heart rate" section for AQA A Level Biology. This includes: electrical activity via the SAN & AVN, the medulla oblongata and how pressure + pH changes affect the control of heart rate. Times stamps are in the comments.
I also go through some 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!! :)
Images:
studyrocket.com
Arizona State University

[@AlevelBiologyHelp]

00:35 = Introduction
01:29 = Electrical activity: Sinoatrial node (SAN)
03:49 = Electrical activity: Atrioventricular node (AVN)
07:53 = Control of heart rate : medulla oblongata
09:22 = Response to changes in pressure
12:22 = Response to decreased pH levels
14:36 = Exam questions and mark schemes

[@Letik3x]

Thank you - my teacher taught this topic today , I had no idea what’s going on … you explained it so well 🎉😊

[@rosia_li]

Thank you so much for these videos! they have been helping me so much in my revision, really appreciate it :)

[@Letik3x]

You know the videos are good if they are Cambridge Medic approves 😂

[@MohamedHassan-zj4bt]

thanks a lot, you helped me so much

[@mikhahl]

Hey idk if anyone is still here after a year, but could someone explain why there is no effect on the stroke volume at 21:05? We can see that contraction A with acetylocholine has slightly more force, would it affect stroke volume or can we find that out from some other factors?

[@AlevelBiologyHelp]

Hi, the graph shows that the force stays the same, so there is no effect on the stroke volume. Hope this has cleared it up for you, but please say if it hasn't :)

[@nazish47]

Thank you so much! Do we need to know about acetylcholine and noradrenaline when talking about heart rate speeding up or slowing down for AQA?

[@AlevelBiologyHelp]

Hi! Yes, I somehow forgot to mention them in the video (woops). Acetylcholine is released from the SAN in response to high blood pressure to decrease heart rate. Noradrenaline is released from the SAN in response to low blood pressure to increase heart rate.

[@nazish47]

@@AlevelBiologyHelp Thank you so much!

[@gaanavmanyam9214]

Where are these questions from? Are they from past papers?

[@seokjinkim9604]

can I ask if "waves of electrical activity" is same as the "electrical impulse"?
thanks,

[@AlevelBiologyHelp]

Yes :)

[@seokjinkim9604]

@@AlevelBiologyHelp thank you so much :)

[@juliettecurran3173]

HI if anyones here a year after... I got the right answer for 1(b) but used different working out, would I still get the two marks? I found that 5 beats occur in 8 seconds, so did 60/8=7.5 and then 7.5x5= 37.5bpm.

[@AlevelBiologyHelp]

Yes you would :)

[@aia8785]

Does this apply to ocr

[@ding-dongditch8773]

I dont know

[@aia8785]

@@ding-dongditch8773 my guy I done ask time ago thanks for trying tho

[@ding-dongditch8773]

@@aia8785 anytime man

[@bruceterbear40]

nah

[@aminahsyeda6252]

lol carotid artery