Edexcel Biology B (A-Level) 2019 thread

Reply 100

fgur987

11

What u guys think you got?
You think paper was harder or easier than last year?

Reply 101

aqauamarine

2

What did everyone put for how resting potential was maintained?
I said it is maintained by the sodium potassium pump because when it drops to -90mv after depolarisation, the sodium potassium pump ensures it comes back to -70mv. And then I mentioned how sodium channels close and potassium channels open but I don’t remember wording.
My friend said there was more to it because it was a 4 marker but I wasn’t sure

Reply 102

aqauamarine

2

Also for the cat question were they talking about enzymes or thermoregulation?
Because I said that in cooler regions the enzyme that changed shape was inactive and so normal melanin pigment can be made, causing the fur there to be black but I feel like that was wrong

Reply 103

username4402068

11

I thought the paper was easier than paper 1 because there was more biology content, has anyone got any predictions for paper 3

Reply 104

aspiringmedic000

10

Original post by aqauamarine

What did everyone put for how resting potential was maintained?
I said it is maintained by the sodium potassium pump because when it drops to -90mv after depolarisation, the sodium potassium pump ensures it comes back to -70mv. And then I mentioned how sodium channels close and potassium channels open but I don’t remember wording.
My friend said there was more to it because it was a 4 marker but I wasn’t sure

I wrote about the sodium-potassium pump as well. That Na+ is pumped out of the neurone but the membrane is impermeable so it cannot enter again. I also said K+ is pumped into the neurone but leaves and goes back out via the K+ channels by diffusion. So there are more cations on the outside so the inside becomes -ve...so the resting potential is maintained at -70 mv.

Reply 105

mini.me

14

any predictions for paper 3??

Reply 106

TheOnlyIzzy

18

This is what I can remember of the questions, its been 24 hours now so I can post them :smile:

enjoy!

Edexcel Biology B alevel paper 2019 (13 June 2019)

1. (Siamese cats)

Put the mRNA code for this DNA?
some amino acids are coded for by multiple codons, what’s this called? (MCQ)
Which bonds do the secondary and tertiary structure have ? (MCQ)
Siamsese cats why are the white bits and brown bits different ?

2. (Octopus Paralysis prey)

What are phospholipids made of? (MCQ)
maintaining a resting potential?

3. (Phytcrome flowering)

Question on far red light, day length and the plants diagram?

4. (Hevs recessive genetic disease allele)

Work out hardy weinburg equation for ____?

5. (Corn)

(Digenic cross) wrinkled/smooth yellow/purple Corn?

6. (Ebola Virus)

Which one produces reverse transcriptase? (MCQ)
Describe the lytic stage of a virus?
Describe the latency stage of a virus?

7. (Glycogen)

What bond does water form? (MCQ)
Which bond does glycogen break glucose down? [hydrolysis/condesation..] (MCQ)
Which diagram shows glycogen? (MCQ)
How is glycogen adapted for its role?
How does adrenaline increase conc of glucose in blood? (cAMP?)

8. (The new volcanic island: ecosystems)

What’s an Ecosystem?
How did the island develop? (primary succession?)
Work out the species index?
Why is species index better than just number?
Comment on the effect of introducing the snakes to bird species?

9. (Babies alveoli lung surfactant)

work out the C__ of the unaffected baby?
analyse data to comment on what’s best for baby (A, B, control)?

Reply 107

octavarium73

9

How are people preparing for paper 3? Not sure what to do other than the past papers :/

Reply 108

jesuisrene

OP

8

Same I'm just going over the practicals

Original post by octavarium73

How are people preparing for paper 3? Not sure what to do other than the past papers :/

Reply 109

T-wreckz

5

Im gunna fail this paper 3 so bad. Im an independant student with o.o.u and just dont have the hands on knowledge for these practical questions . Reading the textbooks and youtube videos just doesnt do it for me. Im interested in biology but really dont care about rates of respiration from a seed or photosynthesis from a twig under different environmental conditions. Such a booooor. Apologies to all you budding experimental biologists. Im feelin positive though overall, i reckon I just need a couple more marks in order to achieve my 48 ucas points for 2 alevels. Livin the dream baby. Zoology next year. Thats what im doin. Hopefully.

Reply 110

username4402068

11

Original post by T-wreckz

Im gunna fail this paper 3 so bad. Im an independant student with o.o.u and just dont have the hands on knowledge for these practical questions . Reading the textbooks and youtube videos just doesnt do it for me. Im interested in biology but really dont care about rates of respiration from a seed or photosynthesis from a twig under different environmental conditions. Such a booooor. Apologies to all you budding experimental biologists. Im feelin positive though overall, i reckon I just need a couple more marks in order to achieve my 48 ucas points for 2 alevels. Livin the dream baby. Zoology next year. Thats what im doin. Hopefully.

Hi if you need help skim through the methods on physics and maths tutor practical section then after that have a look at old spec unit 3 and unit 6 papers, then attempt the three paper three available. Remember what came up probably won’t be assessed again on these papers and take note of all the practicals in 2017 and 2018 and even the specimen paper, they’re most likely to go for something people wouldn’t have seen! That should give you an edge and also remember that normal content can come up to so make sure your up to date with that