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Reply 60
123trident
Yeah mine was like yours, what was the axis labelled on both sides? If we know them then we can probably see if were wrong


The left-hand side axis was the concentration of the substrate :smile:
Reply 61
Vanny17
What did you write for movement of substances into the cell membrane?


Active transport, Facilitated diffusion of water soluble substances and normal diffusion of lipid soluble substances

:smile: lol
Reply 62
123trident
Yeah mine was like yours, what was the axis labelled on both sides? If we know them then we can probably see if were wrong

In the x axis it was time in seconds and in the y axis it was blood something concentration. I think we got it right:smile:
Reply 63
chipsnfish
Not entirely the same , the things in bold with a few of my own. Which questions did you find hard, i didnt know how to answer the artery one as I didnt think heart disease would come up again. How did you revise btw, nelson thornes?


For that i wrote the atheroma would take longer to constrict the lumen enough for a thrombosis to form or anuerysm to form ... also wrote that the blood flow would not be restricted as much if the lumendiameter was large so risk of CHD decreases ... i put sumfin else in cant remember what
Reply 64
Was the first question
Circular DNA
Smaller ribosomes (70subunit) and
Capsule right??
Reply 65
Vanny17
I will get only one mark then i said that is moves by osmosis from a high water potential to a low water potential from lumen to cells

I think you didn't need to talk about protein channels opening up in this one.., You prob got full marks..:biggrin: :biggrin: :biggrin:
Reply 66
Vanny17
In the x axis it was time in seconds and in the y axis it was blood something concentration. I think we got it right:smile:


yeah if it is measuring the blood conc, then at first there is alot of the molecules absorbed in the blood because the enzyme breaks down the substrate, then it decreases because the molcules/products are used up by the cells over time. Also there was a question on this in a past paper, it had the same shapes of the curves as ours did, so we prob got it right
123trident
yeah if it is measuring the blood conc, then at first there is alot of the molecules absorbed in the blood because the enzyme breaks down the substrate, then it decreases because the molcules/products are used up by the cells over time. Also there was a question on this in a past paper, it had the same shapes of the curves as ours did, so we prob got it right


I can't see where you're coming from. It was Concentration of the Lipid on the Y axis and Time on the X axis.

One person couldn't digest it, so the line stayed parallel to the x axis. The other person could, so the line levelled off towards the x axis.

Why would it arc? They were given a static concentration. It can't possibly increase. The amounts of PRODUCT might increase, but that wasn't what they were asking. They were asking about the concentration of the lipid, which is broken down, and thus is just a straight up decrease.
Reply 68
I went for potassium ions for the ORS, I think Na is right too.
Reply 69
TwilightKnight
I can't see where you're coming from. It was Concentration of the Lipid on the Y axis and Time on the X axis.

One person couldn't digest it, so the line stayed parallel to the x axis. The other person could, so the line levelled off towards the x axis.

Why would it arc? They were given a static concentration. It can't possibly increase. The amounts of PRODUCT might increase, but that wasn't what they were asking. They were asking about the concentration of the lipid, which is broken down, and thus is just a straight up decrease.


:yep:
It was definitely a line parallel to the x axis (or very slowly decreasing) and then a curve/line down touching or nearly touching the x axis

ORS = Na/K/Citrate ions
Vanny17
I will get only one mark then i said that is moves by osmosis from a high water potential to a low water potential from lumen to cells

That will get both marks
Reply 72
Vanny17
Was the first question
Circular DNA
Smaller ribosomes (70subunit) and
Capsule right??


I put Plasmids, Cell wall and flagellum.
Reply 73
Hey and what about the vaccination question?

The antigen is a protein on the surface membrane of the virus ( or cell invaved by the virus) that isn't recognised as self by the immune system and thus triggers an immune response.

IS that okay? to write antigens could be on cell invaded by the virus ?
on the pancreas question, when it said 'why does the cell contain lots of organelle G', organelle g was a mitochondrion wasn't it?
Reply 75
.:VivaLaVida:.
on the pancreas question, when it said 'why does the cell contain lots of organelle G', organelle g was a mitochondrion wasn't it?


Yeah you are right! :biggrin:

Mitochondria manufactures ATP
Energy source for Metabolic activities hence
Energy source for protein synthesis
of Excretory cell.

that would get u three marks I think :pwnd:
Ok gonna try and come up with a mark scheme tell me if I miss anything which I undoubtedly will!!

1) a) Flagellum; capsule; 70s ribosomes; mesosomes; plasmids; peptidoglycan cell wall;

b) lowers water potential in lumen of intestine;
water moves by osmosis from cells;

c) to kill pathogens/sterilise;

d) sodium/salt/potassium/chloride;

2) a) volume of air in lungs increasing;

b) diaphragm contracts;
flattens and moves down;

c) PV= tidal vol x breathing rate;
more exaggerated peaks higher tidal volume;
peaks cloers together higher breathing rate;

3) peptide;

b) H, J, E;

c) site for aerobic respiration/produce ATP;
secretes lots of enzymes/products;
needs energy to make them;

d) homogenated breaks open cells;

e) filtered removes debris;

f) cold reduces enzyme action;

g) isotonic same water potential as tissue/organelle;
stops organelle shrivelling bursting;
by osmosis;

... another Qu after this?

4) no;
correlation not causation;
another factor/ need scientific studies/ HPV16 should be investigated;

b) protein / glycoprotein;
on HPV virus stimulating immune response/production of antibodies/memory cells;

c) memory cells secondary immunity;
divide rapidly by mitosis to form plasma cells;
produces lots of antibodies;
eliminate infection quickly;

d) low pH in stomach/pepsin;
denatures/digests enzymes;

e) boys could have sex with girls that have HPV;
may act as carriers/transmit to other girls;

5) a) spc. tertiary structure;
specific active site shape;
only substrate complementary/binds/fits;
to the active site;

b) straight line paralell to x/decreasing slightly;

c) decrease to low level/0

definitely another question...

6) smoking;
high blood pressure;
stress;

b) healthy volunteers have no underlying conditions/may react differently in unhealthy people;

c) avoid sampling bias;

d) dark chocolate without flavanoids;
otherwise treated exactly the same;

e) structure of artery in arm similar to that in coronary arteries;
higher blood pressure;
inc. risk of aneurysm;
thrombus/atheroma reference;

7) a) simple diffusion/diffusion;
through p.lipid membrane;
water and small molecules;

fac. diffusion;
channel/carrier proteins;
specific;
larger/charged substances;

both above passive/down conc gradient;

active transport;
needs ATP;
hydrolysed/conformation change;
in carrier proteins;

b) alveoli convoluted/good blood supply;
large surface area;

thin alveolar epithelium and capillary endothelium;
short diffusion pathway/distance;

movement of air and blood;
maintains diffusion gradient;

Ok there is a makeshift mark scheme but I need you guys to remind me of the other questions :P
Reply 77
:ninja2: :ninja2: Wow you are a legend mate.You can actually remember the whole exam! lool:pcguru:
Reply 78
RodrigoB
:ninja2: :ninja2: Wow you are a legend mate.You can actually remember the whole exam! lool:pcguru:

how did you find it rodrigo?
Reply 79
I wrote

Diaphragm stretches and flattens increasing the thorax volume

will they give me marks for that?