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A-level Biology SNAB 2019

Alright so I thought i'd make a thread for the SNAB biology students.

Basically heres a list of the topics that could be 9 markers in the 2019 paper and I thought it'd be good to discuss:ATP, Calcium,Chemical and electrical gradients, Endocytosis, Enzymes, Exocytosis, Hydrolysis, Phosphorylation, Sodium , Potassium and Chloride, Water, Complementary binding and Condensation.

Now the ones I think have a good chance of coming up are Enzymes,Water and Complementary binding. There may be a chance the others show up if enough information is given on them. But yeah feel free to discuss any other things in the paper and share ideas.

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So we've already been given a 9 marker on the cell membrane and carbohydrates, some really good answers on the examiners reports and i'm sure they might ask a 5 marker on them again.

Enzymes is a pretty basic topic and easy 9 marker to be fair but if it came up i'd think talking about the importance of it in plants and animals, what it is in general, so protein molecule that catalyses a reaction and like how its formed so primary secondary and tertiary structure. Give some examples of enzymes in plants like rubisco and some important enzymes such as ATPase and ATP synthase. They might give us some graph data to refer to such as pH and temperature graphs and how we refer back to the data and why they get activated. And then probably a conclusion of enzymes like how important it is in all life functions and how we wouldn't be alive without them.

I have doubts they'd ask such an easy 9 marker so they might focus on one aspect on enzymes so if you talk about the others you might not be able to get more marks cause of "irrelevant information" as seen in the 2017 paper. But if they did I'd assume the rest of the paper would be harder soooo lets pray they ask it with the rest of the paper being easy lol.
One of my teachers said lipids is likely to come up this year? I think there's also a chance of:
- H bonds
- metabolic reactions (got a practice q on this from my teacher it was kinda wack didn't really know what to say!)
- proteins
- hormones
- ATP
- gradients (like diffusion/electrochemical gradients idk)

edit:
just thought of membranes too lol
Hmmm lipids came in 2017 but not directly. It was the importance of proteins or lipids in the cell surface membrane, but yeah if they did ask again I guess you could talk about triglycerides, phospholipid bi layer, glyco lipids, ummm can't think of any more off the top of my head, do you know anymore?

Hydrogen bonding definitely seems like a viable question, what I can think of at the moment on that is the hydrogen bonds in proteins, in the cell wall, between bases, in water and how it gives water its properties, again if you got any more ideas feel free to share:smile:

Proteins is also a pretty possible one, enzymes, protein synthesis, glycoproteins, channel and carrier proteins, and then I guess giving specific examples.

Hormones seems some what limited to topic 7 and 8, and not really broad but I guess you talk about auxin and peptide and steroid hormones. There could well be a question on compare and contrast the hormones in plants and animals which could be 4/5 marks in paper 2/3

ATP is also pretty good pick, my teacher gave me one on phosphorylation and the importance of that, so I guess you talk about how its used in plants for Kalvein cycle, and how its used in muscle contraction and regenerated in respiration and the enzymes involved.

I looked at electro chemical gradients and I could only find examples in topic 2 for changing mucus viscosity and in the stalked particle in topic 7. If it was diffusion then yeah i guess they could ask that, so facilitated and osmotic.

If it isn't any trouble could you send that metabolic reactions practice q with the ms thanks lol.

Original post by pseudo123
One of my teachers said lipids is likely to come up this year? I think there's also a chance of:
- H bonds
- metabolic reactions (got a practice q on this from my teacher it was kinda wack didn't really know what to say!)
- proteins
- hormones
- ATP
- gradients (like diffusion/electrochemical gradients idk)

edit:
just thought of membranes too lol
For lipids you could also talk about HDL/LDL possibly? Not sure if that would count though
for H-bonds I would mention what you said - proteins (like between R groups), water and its properties/cell walls but I think I'd also mention something about hydrogen bonds in the DNA between the nitrogen bases?
For electrochemical gradients there's a bit in photosynthesis as well because the H+ ions are pumped down an electrochemical gradient, and I think in action potentials/synapses Ca2+ ions diffuse down an electrochemical gradient into the presynaptic neurone? So I'd probably mention those too :smile:

Our 9 mark practice Q wasn't a full on written one unfortunately and we really just ended up talking about it! The question was just something like 'assess the importance of metabolic pathways to organisms' so we discussed how metabolic reactions allow the formation of vital substances for the body like ATP (for muscle contraction in aerobic respiration) and photosynthesis for plants etc. I can send you my mindmap if you want though!
Original post by LightningLorenzo
Hmmm lipids came in 2017 but not directly. It was the importance of proteins or lipids in the cell surface membrane, but yeah if they did ask again I guess you could talk about triglycerides, phospholipid bi layer, glyco lipids, ummm can't think of any more off the top of my head, do you know anymore?

Hydrogen bonding definitely seems like a viable question, what I can think of at the moment on that is the hydrogen bonds in proteins, in the cell wall, between bases, in water and how it gives water its properties, again if you got any more ideas feel free to share:smile:

Proteins is also a pretty possible one, enzymes, protein synthesis, glycoproteins, channel and carrier proteins, and then I guess giving specific examples.

Hormones seems some what limited to topic 7 and 8, and not really broad but I guess you talk about auxin and peptide and steroid hormones. There could well be a question on compare and contrast the hormones in plants and animals which could be 4/5 marks in paper 2/3

ATP is also pretty good pick, my teacher gave me one on phosphorylation and the importance of that, so I guess you talk about how its used in plants for Kalvein cycle, and how its used in muscle contraction and regenerated in respiration and the enzymes involved.

I looked at electro chemical gradients and I could only find examples in topic 2 for changing mucus viscosity and in the stalked particle in topic 7. If it was diffusion then yeah i guess they could ask that, so facilitated and osmotic.

If it isn't any trouble could you send that metabolic reactions practice q with the ms thanks lol.
I never heard of those reactions being termed as metabolic reactions in SNAB, so when I read that I was thrown a bit off lol, yeah please if it no trouble could you seen the mind map. I don't mind sending my 9 marker as well if you want it, its on phosphorylation:smile:
Original post by pseudo123
For lipids you could also talk about HDL/LDL possibly? Not sure if that would count though
for H-bonds I would mention what you said - proteins (like between R groups), water and its properties/cell walls but I think I'd also mention something about hydrogen bonds in the DNA between the nitrogen bases?
For electrochemical gradients there's a bit in photosynthesis as well because the H+ ions are pumped down an electrochemical gradient, and I think in action potentials/synapses Ca2+ ions diffuse down an electrochemical gradient into the presynaptic neurone? So I'd probably mention those too :smile:

Our 9 mark practice Q wasn't a full on written one unfortunately and we really just ended up talking about it! The question was just something like 'assess the importance of metabolic pathways to organisms' so we discussed how metabolic reactions allow the formation of vital substances for the body like ATP (for muscle contraction in aerobic respiration) and photosynthesis for plants etc. I can send you my mindmap if you want though!
has anyone got the locked spec papers for this spec? i need more practice questions !
I tried searching for them as well and I don't think anyone has them, if you need topic 1 to 4 questions the AS papers are good cause they are new spec. Theres not really many questions as it is a new spec so try doing some old spec questions and read the examiners reports of the 2017 and 2018 papers as they contain really good advice and will get you in the mindset of how to answer the questions. And as long as you've revised all the topics and know the last years papers really well you should doooo pretty good, hopefully.:smile:
Original post by wholesomememes
has anyone got the locked spec papers for this spec? i need more practice questions !
hows everyone feeling bout paper 1 we've stillgot over 2 weeks
I'm feeling alright you know. Its topics 1 to 6 so I guess they'll ask a lot of the basics and then probs a question on immune response. They might link some topics together like 4 and 5. But overall I guess its pretty good. I mean the grade boundaries for an A* for the last two years was 197 and 200 out of 300, which is around 66%. So if we try and aim for 70 - 80 percent in each paper which is still 20 to 30 marks leeway to lose like thats a lot of marks. So hopefully it goes well.
How about you :smile:
Original post by applesandalevels
hows everyone feeling bout paper 1 we've stillgot over 2 weeks
my first bio exam is this Tuesday :frown:
Original post by applesandalevels
hows everyone feeling bout paper 1 we've stillgot over 2 weeks
I don't know what spec of qualification lol but good luck I guess:smile: hope you ace that ****:biggrin:
Original post by hajerox123
my first bio exam is this Tuesday :frown:
If a question came up on complementary binding these are the things I'd think to write, share some more if you want:
-Enzymes binding to substrate complexes and how they have a complementary specific shape. This is so only specific molecules bind to these enzymes and are catalysed.
-Bases being complementary to each other. This makes it so the mRNA strand that is copied of the new DNA strand produced in semi conservative replication is identical, if it wasn't then there would be mutations as the possibility of a stop of start codon could be introduced producing shorter polypeptide chains.
-Codons and Anti codons being specific. This is again similar to the last reason the polypeptide chain of amino acids different coding.
-Receptors on the cell surface being a specific complementary shape. This is so the body is aware of antigens and then you could give the example of the CD4 receptors on the macrophages and how HIV has GP120 which allows it to complementary bind and cause a very dangerous disease.
Then overall you'd sum up that complementary binding is very important and how it prevents all of the above.
It is the AS exam paper
Original post by LightningLorenzo
I don't know what spec of qualification lol but good luck I guess:smile: hope you ace that ****:biggrin:
its SNAB but AS
Original post by LightningLorenzo
I don't know what spec of qualification lol but good luck I guess:smile: hope you ace that ****:biggrin:
do yu have it too?
Original post by ntoufiq
It is the AS exam paper
No, I'm doing A level this year. How did it go- What sort of topics were on it?


Original post by hajerox123
do yu have it too?
ooo yeah maybe there will be similar topics in our one, if not its still good revision for those types of questions.
Original post by ntoufiq
No, I'm doing A level this year. How did it go- What sort of topics were on it?
Original post by LightningLorenzo
ooo yeah maybe there will be similar topics in our one, if not its still good revision for those types of questions.


Anyone one who knows what came up on today’s AS edexcel a paper please let me know
im waiting for twitter to do its thing ahha

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