A2 Biology OCR June 2015 Revision Thread

I see what you mean, but sympathetic neurones (regardless of being involuntary) innervate muscles, simply not skeletal ones, hence why sympathetic action is able to increase heart rate, by having an effect on cardiac muscle.

In this way, these neurones meet muscle cells at a junction, surely this is a neuromuscular junction? If a neuromuscular junction applies only to the junction between somatic motor neurones and muscle fibres then I can see where my confusion has arisen. However, if not, I still can not understand why noradrenaline is being quoted as the neurotransmitter at this junction?

at a synapse? Synapses are neurone to neurone. Not at the NMJ, the NMJ is always ACh only.

Yeah it is confusing I got confused about it too when I made my notes on this topic.

A neuromuscular junction only applies from a motor neurone to a skeletal muscle.

Cardiac muscle and smooth muscle are innervated by some other mechanism, for some reason. We just need to know about the case of a neuromuscular junction from motor neurone --> skeletal muscle.


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Yeah it is confusing I got confused about it too when I made my notes on this topic.

A neuromuscular junction only applies from a motor neurone to a skeletal muscle.

Cardiac muscle and smooth muscle are innervated by some other mechanism, for some reason. We just need to know about the case of a neuromuscular junction from motor neurone --> skeletal muscle.


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I am so often confused, I think it may have become a permanent personality feature, haha.

Thanks for clarifying, it just seems odd that there is a junction between a neurone and a muscle and we can't call it a neuromuscular junction. Semantics!

It says between a neurone and an effector, such as a muscle.

Galapagos. I'm so worried.

Haha.

But seriously, do you think there are any topics likely to come up? based off whats not come up for a while. Have your teachers said anything?

Haha.

But seriously, do you think there are any topics likely to come up? based off whats not come up for a while. Have your teachers said anything?

For f214: don't think insulin secretion has been on for a while, action of cAMP and adrenaline etc. and labelling graphs to do with action potential, insulin production using GM bacteria, I think there will be quite a lot more photosynthesis stuff as it was only on a bit last year (a few 1 markers and 2 markers) when I sat the paper, on last years paper the respiration question was to do with fruit and veg and more about data analysis rather than knowledge so it could possibly come up more

Could anybody help me ? I have covered all the unit 5 content like made notes but I cannot answer a single question without looking back at my notes how do I revise so that I can actually answer questions ?!

Unit 4/5? Things that haven't come up a huge amount? I haven't done enough papers to say, sorry. Give me a week or so.

Everything unit 4 that comes up is so obscure, just make sure you try having a holistic approach rather than focusing on the big parts

Oh awesome, thanks. I've only done a couple past papers for f214/5 hope to do like 8-10 each before the exams.

So you're resitting? Are you in your gap year? What did you get last yr?

Yes I am I was on an A at AS but my A2 dragged it down to a C unfortunately

Have you ever seen the "beta-oxidation pathway" in an f214 paper before? I've only done a couple, but throughout the year of class tests, i've never seen it before, maybe that'll come up?

It has come up quite a bit, it relates to excretion and detoxification of alcohol as it uses NAD. You'll be fine though. If I were you I'd learn content before banging out those papers because there are so few of them