The Student Room Group
Uni students - Complete our survey >>
Uni students - Complete our survey >>
Uni students - Complete our survey >>

AQA A-level Biology Unit 1 26th May 2016

Scroll to see replies

Original post by EmmaHarvard
Question was talking about into epitheilal cells not blood. Could get penalised.


Hmmm but I'm sure you have to say that they are AT into blood then this leads to a lower conc in the cells right...
Reply 81
Avatar for srkd
srkd
1
The exam was very difficult, I thought. :/ Hopefully the grade boundaries are lower than 45. :/
Original post by A2LEVELSHELPME
how did you draw the graph at 15 degree?


Started from the same point and met the curve for 25 degrees at around 3/4 minutes
(Did not go lower than the curve for 25 degrees)
(Less negative gradient compared to 25 degree)
Original post by A2LEVELSHELPME
how did you draw the graph at 15 degree?


I did it staying horizontal a bit longer and the decrease slightly less steep than the other temperature but it plateaued at the same place as the first graph
No shut up u butt
Original post by FlowaPowa
I did it staying horizontal a bit longer and the decrease slightly less steep than the other temperature but it plateaued at the same place as the first graph


Yep sounds right


Posted from TSR Mobile
Original post by piggywag1
Started from the same point and met the curve for 25 degrees at around 3/4 minutes
(Did not go lower than the curve for 25 degrees)
(Less negative gradient compared to 25 degree)


sounds about right thanks
Most times the unofficial mark schemes are 100% wrong, so am not relying on them
For the ph meter I said it gives an quanititative reading.

whereas using indiciator means you need to see colour change which is subjective.

The one about the why results of the lactose intoelrance thing be unreliable, I said because the severity of symoptoms is subjective, will vary from person to person.
Original post by Kira Yagami
For the ph meter I said it gives an quanititative reading.

whereas using indiciator means you need to see colour change which is subjective.

The one about the why results of the lactose intoelrance thing be unreliable, I said because the severity of symoptoms is subjective, will vary from person to person.


Yeah I also put the subjectvieness with the symptom severity, but for the pH meter one I also put how the quantitative reading was continuous so it could be plotted as a curve on the graph rather than discrete colour changes
Reply 90
Avatar for 02PC03
02PC03
1
Can anyone post the questions
Reply 91
Avatar for Bennyab
Bennyab
2
Original post by EmmaHarvard
Can anyone please make an unofficial mark scheme?


From what I remember:
2 ticks in top right corner, 2 ticks in bottom left
2.8
Free floating DNA or no nucleus
Mitochondria atp production - active transport, muscle contractions

Ribosomes
Peptide bonds
Competitive inhibition - similar shape, binds to active site, forms enzyme substrate complex

Diaphragm relaxes, moves upwards, some shaped, pressure increases, volume of thorax decreases

Heart - c and a
Valve means blood leaks back into atria, less entering aorta via semilunar valve, less blood pumped to tissues

Immunity - they do not have receptor protein so Ebola viruses cannot enter cells, virus must colonise cells to replicate, virus destroyed
Plasma cells one - secondary rapid response, memory cells involved
Blood transfusion- antibodies have specific hydrogen bonds in primary structure, specific tertiary structure, variable religion specific, binds to antibody to form antigen-antibody complex, virus destroyed

Sodium ions - sodium potassium pump actively transports sodium ions into lumen, requires atp, epithelial cells have lots of mitochondria, micro villi increases surface area, sodium lowers water potential in cells so glucose diffuses into cells

Chloride ions - no clue, messed up on this one


Posted from TSR Mobile
Someone make an unofficial mark scheme please


Posted from TSR Mobile
Original post by FlowaPowa
Yeah I also put the subjectvieness with the symptom severity, but for the pH meter one I also put how the quantitative reading was continuous so it could be plotted as a curve on the graph rather than discrete colour changes


Yeah makes sense.
For the one about whole between the vent and atria..

I said blood would flow back into atria so less blod would be pumped around the body.

Blood carries oxygen so there would be less blood flow to cells so they would receive less oxygen..

/ diffusion gradient is reduced...

Something like that.
Am i the only one who prefers Unit 2 to Unit 1?
Original post by Kira Yagami
Hmmm but I'm sure you have to say that they are AT into blood then this leads to a lower conc in the cells right...


You're right. The question is just asking you to describe co-transport. It is the first step as there has to be a concentration gradient for the sodium ions to diffuse in from the lumen of the intestine.
Original post by maggie43
Am i the only one who prefers Unit 2 to Unit 1?


I prefer unit 2 but not as prepared for it 😬
Original post by FlowaPowa
I prefer unit 2 but not as prepared for it 😬

Me too but we have got a week to go. Hopefully it is so much better
Reply 99
Avatar for Bennyab
Bennyab
2
I reckon 52-ish here? The last questions rekt me, was not expecting bs like that tbh. Anyone need help on any questions? See if we got same answer


Posted from TSR Mobile

Quick Reply

Related discussions

Latest

Trending

Trending

Articles for you