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AQA AS Biology 7401/1 and 7401/2 Exam - 26th May and 7th June 2016

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Original post by ogu01
Yh that's what I said although I think you may have had to specify that the hairs were around the stomata and it trapped water vapour to reduce water potential gradient between inside of leaf and air


Oh are you sure? I think we don't have to mention the stomata as it said that other than the stomata explain 2 features .... but you are right I guess with your explanation. I think this could be a seperate point.
Original post by AfcFob
I got the same values as you but I ended up writing it as 3.6:1 (there will probably be leeway though)


I wrote 3.5:1 too.
I wrote proteases for the first question lol... Doomed from the start
Is there an unofficial markscheme for this???????????
Original post by 10moorej
I wrote proteases for the first question lol... Doomed from the start


LOL don't worry it was only 1 mark. Some of the people who sat the exam were also saying they put Protease and they were confident with their answer. :biggrin:
The answer was Dipeptidase but I am sure you know the answer now.
For the seeds question did you have to use the data from the graph at all? (apart from the ratio bit)
Original post by rafiuddin
i wrote that some water used up in respiration and some was stored for later use/provide turgidity to cells


isn't it photosynthesis???:s-smilie:
did everyone say for the respiratory inhibitor how it stopped the production of ATP, as the mitochondria were affected (as these are the sites of aerobic respiration) and how the sodium ions were unable to move out of the ileum via the sodium potassium pump, as active transport couldn't take place, hence the amino acid couldn't be absorbed?
Original post by pandasandpens
isn't it photosynthesis???:s-smilie:


yes it is photosynthesis and respiration, as photosynthesis uses water, and respiration produces water
what did everyone get for the HIV CCD5 protein question about why it is produced from random mutations? only question i felt i didn't know the answer to??
Original post by ormlaaaa
did everyone say for the respiratory inhibitor how it stopped the production of ATP, as the mitochondria were affected (as these are the sites of aerobic respiration) and how the sodium ions were unable to move out of the ileum via the sodium potassium pump, as active transport couldn't take place, hence the amino acid couldn't be absorbed?


Pretty much,
I said that a respiratory inhibitor would mean that energy for the carrier protein to change shape wouldn't be released from the hydrolysis of ATP so sodium ions would not be actively pumped out of the cell. This would mean that the concentration of sodium ions inside the cell would remain high and as a result the concentration gradient would be in equilibrium so the sodium ions outside the cell would not move down by facilitated diffusion, bringing the amino acid with it so no amino acids would be absorbed :smile:
Original post by rafiuddin
people with HIV can still have babies (despite the parent not being naturally selected)
people with HIV can survive under medical/quarantine conditions (probs wrong)

I wrote that:
Even if people have HIV they can survive till reproducible age and pass on their genes and hence natural selection doesn't occur to a great extent. It doesn't matter how early they die as long as they pass on their genes.
Original post by ormlaaaa
did everyone say for the respiratory inhibitor how it stopped the production of ATP, as the mitochondria were affected (as these are the sites of aerobic respiration) and how the sodium ions were unable to move out of the ileum via the sodium potassium pump, as active transport couldn't take place, hence the amino acid couldn't be absorbed?


i wrote this but I went in more depth. I said because the sodium ions are unable to move out of the epithelial cells into the blood stream, a diffusion gradient of sodium ions could not be maintained between the cavity of the ileum and the epithelial cells. This prevented the facilitated diffusion of sodium ions and along with it the facilitated diffusion and absorption of amino acids.
Original post by LaurenLovesMaths
I was so annoyed that certain topics, like protein synthesis, meiosis and the actual theory about the lungs and heart didn't come up :frown: I've been getting straight As in all past papers/mocks but these were horrible and I feel like I've gotten a C or maybe even worse :frown:


I don't think it's possible for the exam to contain every single topic but I'm also a little annoyed at the fact that I didn't need to know what feels like a quarter of the specification. There was also nothing to do with statistical tests which I spent God knows how many hours revising.

Grade boundaries are likely to be lower this year by virtue of that fact that this is the first year of the new spec.
Original post by rafiuddin
got 3.86 ish

Mine was closer to yours, it was 3.74 for me.
Original post by Virolite
hydrolysis of ATP produces phosphate which is evidence for respiration occuring

phosphate is also used in the formation of bilayer (cell membrane) which indicates cell division etc..


Exact same answer holler!!
LOLOLOLOL I've failed... Looking through this thread is actually making me depressed
Original post by AfcFob
I got the same values as you but I ended up writing it as 3.6:1 (there will probably be leeway though)


Wrote 40:11 because I didn't feel like rounding up haha
Original post by rafiuddin
higher volume, lower overall pressure
also more blood can leave the heart after each pump
something like that


I wrote that widening of blood vessels increases and this increases the cross-sectional area and hence volume of the vessel. This means the speed of blood flow, to transport the same volume of blood, is lower and hence a lower pressure is needed from the ventricles.
I also wrote volume and pressure are inversely related and hence as volume rises, pressure will inevitably decrease.
Original post by rafiuddin
people with HIV can still have babies (despite the parent not being naturally selected)
people with HIV can survive under medical/quarantine conditions (probs wrong)


1. Mutations are completely random and not caused by anything (I think the question didn't suggest that it was random so)

2. Maybe HIV cases were low so there was in fact little or no selection pressure

Idk lol I didn't like this question

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