00:28= Haemoglobin, oxyhaemoglobin dissociation curve and the Bohr effect 08:09 = Circulatory system of mammals 10:28= Gross structure of the human heart 13:44 = Cardiac cycle (volume and pressure changes) 17:20 = Adaptations of blood vessels - arteries, arterioles, veins and capillaries 20:57= Formation and return of tissue fluid 23:20= Exam questions and mark schemes

You can remember the valves with LABRAT - Left atrium bicuspid & right atrium tricuspid. Hope this helps!

@jameschristopher2540

3 жыл бұрын

Yeh thanks 🤩 that helps

@jameschristopher2540

3 жыл бұрын

I added my own with LABVRATV for left ventricle and right ventricle. Work out which ventricle is right/left by looking at first letter for each part e.g. labv is left ventricle, ratv is right.

@jameschristopher2540

3 жыл бұрын

Did the exam an worked like a charm

@kelv5459

2 жыл бұрын

Don’t need it for AQA you can just say atrioventricular valves

@form.of.dhikr2

2 жыл бұрын

@@jameschristopher2540 Bismillah, tricuspid has ri in it for right. The other (bicuspid) must then be left.

This person is single handedly saving my a levels

I've never understood tissue fluid, like what is is, how it was formed, etc, but seeing your explanation, pausing the video to answer the exam questions and then actually getting some marks for it is amazing! Thank you so much ❤️

@AlevelBiologyHelp

3 жыл бұрын

That's so great to hear!

hi, this was such a good video! could you pls do a vid where you go through questions on the bohr effect and dissociation curve?

I have my mocks next week, this video really helped, thank you so much!!:)

I have my Biology Y12 mock soon on the AS content and its hard with missing so much school this year due to Covid but ur videos have helped me get through all the content in time and revise them too, thanks soooo much, your time and effort put behind all these videos means so much to all us students out here. If we do well in our exams your deserve all the appreciation. THANKYOU so much again, your such a hero 😊

@AlevelBiologyHelp

3 жыл бұрын

Aw that's so nice! You're very welcome, I hope your mock goes well! :)

This is an amazing video thanks! To remember bicuspid and tricuspid valves, I’ve always thought that tRIcuspid has ri in it as in RIght, so that must be on the right side of the heart! Again thanks for the video, I found it extremely helpful for my exams :)

@AlevelBiologyHelp

3 жыл бұрын

So glad I could help!

at 12:12 I think your fine with saying atrioventricular valve for both as my teacher says its fine and i have put that down for my topic tests and other assessments and still get the mark however i also think learning them can be kind of helpful too

the whole of this chapter was a complete blur to me but this video really helped me break it down into simpler sections on my flashcards so thank you! i'm slightly more confident now if this were to appear in my final a level exams coming up this may/june!

My greatest thanks.

The drawing of the Bohr shift curve was 𝘌𝘟𝘊𝘌𝘓𝘓𝘌𝘕𝘛. I'm definitely not going to forget 😂

@AlevelBiologyHelp

2 жыл бұрын

I've honestly never had a steady hand 😭.

thanks so much for these helpful videos !!

Love your videos thanks for helping out!

@AlevelBiologyHelp

3 жыл бұрын

So glad I could help! :)

I really appreciate your work thankyou so much

@AlevelBiologyHelp

3 жыл бұрын

You're very welcome!

Thankyou for this!!!

Do you have a video on cardiovascular problems like atheromas etc? Thanks!

Remarkable vid I applaud you for your efforts. Appreciate this as ill be sitting a test in an the or 2.

@AlevelBiologyHelp

3 жыл бұрын

Thank you! Good luck with your test!

@jameschristopher2540

3 жыл бұрын

@@AlevelBiologyHelp thank you for that ur vid helped a ton. It really showed when I attended class that I felt confident an a bit bored. I mistakenly revised for my test even though it’s on Wednesday (it was beneficial though). I’ll take the good luck an keep it for Wednesday. I have to pass this since I was brought a year back from a levels so my last chance I guess.

@jameschristopher2540

3 жыл бұрын

@@AlevelBiologyHelp ur “ve-in towards the heart” saved me in a whole load of questions so thx for that. Did my exam like 2hrs ago, ur vid game me the knowledge an hope of revising I needed. I’m class on Monday I was bored only because I knew everything she was going to say before she said it. I feel bored when I’m confident with knowledge an man was I bored thx to ur vid. I’ll definitely recommend ur vid 👍

You're amazing !

merci cela m'a aidé à commencer à apprendre l'anglais et j'aime le chocolat

Fantastic

Brilliant video

@AlevelBiologyHelp

3 жыл бұрын

Thanks 👍

youre amazing

to remember the valves in the heart just think try before you buy

Hey I wanted to ask are your videos ACCURATE and mark scheme SPECIFIC? I see lots of biology AQA A-Level videos with mistakes and content that goes off tangent. thanks

@AlevelBiologyHelp

3 жыл бұрын

So sorry for the late reply! Yes, my videos are specific to the AQA specification, so I don't mention anything that you don't need to know. I also try to use phrases that gain marks in the exam ☺️

So helpful x

@AlevelBiologyHelp

3 жыл бұрын

You're welcome!

very good video

@AlevelBiologyHelp

3 жыл бұрын

Thank you I appreciate it! 🥰👩‍🔬

I'm doing Eduqas I can't find anyone that does videos for that specification :(

Don't we also need to know about heart problems, because i recall doing an exam question and my teachers talking about the problems of a baby being born with a hole in its heart. Or is it something that isn't compulsory to know but instead that we have to adapt our current understanding of the heart in order to answer that question?

@AlevelBiologyHelp

2 жыл бұрын

No you don't need to learn these! When they come up in the exam, it's to test if you can apply your knowledge to an unfamiliar situation. :)

Is there a formula for % saturation of Hb with O2? And if so, do I need to remember it for the spec?

@AlevelBiologyHelp

3 жыл бұрын

There is a formula but you don't need to know it! Out of interest, it is the concentration of oxygenated haemoglobin divided by conc oxygenated+ deoxygenated x 100

@maisamraza7094

3 жыл бұрын

Thanks a bunch

How old are the tissue fluid questions? I'm sure I've never been taught about 'outward pressure' just hydrostatic pressure

@muhammaduzair3482

3 жыл бұрын

these are relatively new I guess. Outward pressure is just the difference between the arteriole end and the tissue fluid.

@AlevelBiologyHelp

3 жыл бұрын

Yes, I suppose that they're relatively new, but I'm not completely sure what year they're from. Hydrostatic pressure is correct, however for this question, they want to see that you've understood the direction that the pressure acts upon. In this case, it's going outwards from the capillary, so you need to write "outward pressure".

At 24:57 you said the volume increasing would cause the pressure to increase. Wouldnt it cause pressure to decrease?

@AlevelBiologyHelp

3 жыл бұрын

Hi! In terms of hydrostatic pressure (water), increased volume causes increased pressure. This is because if there is increased volume, more water particles are present, therefore the pressure increases. It works differently to gaseous pressure! I hope this makes sense :)

doesn't the presence of increased CO2 change the quaternary structure, not the tertiary structure? as its the quaternary structure that accounts for the different behavior of haemoglobin at different parts of the organism.

@AlevelBiologyHelp

3 жыл бұрын

Hi, the quaternary structure is affected, but conformational changes (e.g. those caused by increased CO2) change the tertiary structure, as that determines the 3D shape of the protein. Hope this makes sense :)

08:59 that does sound silly ! ;(