Year 12s: what will be the first way you research your future options? >>

AQA Biology AS New Spec - 26th May and 7th June

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Reply 280

Namita Gurung

Original post by eleanor99

What type of bond did everyone put for the one mark multiple choice?

I wrote hydrogen

Reply 281

Epitype

Original post by eleanor99

What type of bond did everyone put for the one mark multiple choice?

Hydrogen Bonds?

Reply 282

SANTR

Original post by SM-

Did it not say the B secretase also increased where the question said that the mutation led to A secretase decreased? You know on the last side of the paper. I wrote then add sequence codes for different amino acid sequence which leads to different primary structure so more B secretase is made so more B protein so more plaques in brain.

What was the question before that?

Reply 283

TeenageKillaTurt

If someone finds a unofficial mark scheme could you send me the link please? :smile:

Reply 284

nav5678

Original post by Lola1244

i put day on x axis and rate of hydrolysis on y... is this completely wrong?

no i think thats correct

Reply 285

SM-

Original post by SANTR

What was the question before that?

Why can the both the enzymes act on one substrate basically.

Reply 286

SANTR

Original post by SM-

Why can the both the enzymes act on one substrate basically.

That was the first question, I'm talking about the next one?

Reply 287

aaaabbbbddulll

what are the 3 differences between dna and mrna?

Reply 288

jamiechristie

Original post by nav5678

no i think thats correct

on the graph the rate is on the x - axis because its the independent variable, nobody is stating that.

it also wouldnt have been days

Reply 289

Epitype

RNA has Uracil
RNA has Ribose Sugar
RNA is single stranded

Reply 290

EggFriedRai

Original post by aaaabbbbddulll

what are the 3 differences between dna and mrna?

ribose and deoxyribose
uracil not thymime
short single strand not double helix

Reply 291

CSR98

Original post by SM-

Why can the both the enzymes act on one substrate basically.

the substrate has a tertiary structure that is complementary to both enzymes

(edited 7 years ago)

Reply 292

JTawn

For statistical test did anyone else put standard deviation- since if the standard deviation bars overlap it shows the difference isn't significant?? 😳

Reply 293

aaaabbbbddulll

what about question on how vaccinations produce antibodies? or something like that its a 4 marker

Reply 294

jamiechristie

Original post by CSR98

the substrate has a tertiary structure that is complementary to both enzymes

If you're referring to question 9 about how the enzyme could still act on them, it was because they were isomers. Which means they had the same chemical formula but their structure varied.

Original post by JTawn

For statistical test did anyone else put standard deviation- since if the standard deviation bars overlap it shows the difference isn't significant?? 😳

I put standard deviation, but I'm hearing loads of **** like ELIZA tests and T-Test.
You could use standard deviation to measure the IQR of the mean, the T-Test I'm not sure but it relates to the mean, chi-squared test (?) or ELIZA for color standard. I have no idea what the right answer would be though.

Reply 295

GabbytheGreek_48

Original post by Gswp

yh i agree. the independant variable was time not mass

yeah i did the mass of sucrose at first but then realized it was the days

Reply 296

KingAuthor

I put a sign test (only statistical test we've done) and said it can find differences between both values.

Reply 297

aaaabbbbddulll

for statistical test i put spearmans rank coreelation coeffiecent is that right?

Reply 298

Shelly12334

Original post by aaaabbbbddulll

what about question on how vaccinations produce antibodies? or something like that its a 4 marker

Dead inactive pathogens B cells join onto them and take them in by exocytosis, the antigens are placed on the surface of the B cell and T cell attaches to it stimulating the B cells to divide by mitosis into plasma and memory cells. Plasma cells produce antibodies that the original B cell produces