The Student Room Group
My tips would be to learn the mark schemes.

If it asks you about dissociation curves - left = higher affin, right = lower affin, for one mark.
Explaining the result e.g releases more o2 into respiring tissues / picks up more in lungs.

They bring in some unit 1 stuff too - remember for enzyme stuff:
Change in hydrogen bonds (1)
results in a change in tertiary structure (1)
substrate cannot bind as active site shape isn't complementary (1)
no enzyme-substrate complexes formed (1)

Also, index diversity is likely to come up so know how to do this.
I'd also suggest learning plant theory too, as this hasn't been featured on the exam yet.

Gas exchange - They could ask you with a diagram, or more simply just recall such as "Give 2 features of gas exchange in fish and explain how it is efficient".
Main points to remember: number in brackets indicate marks given for the content
Fish:
Countercurrent system - oxygen constantly obtained from the gradient created (2) - blood runs against water so O2 is diffused as gradient is steep.
Diffusion gradient or diffusion pathway (1)
Occurs across whole gill - large surface area (1)
Gill filaments/lamellae - large surface area (2)

Insects:
Air enters through spiracles (1) spiracles can open/close - prevents water loss
Trachea branch out into tracheoles for large surface area (2)
- which means tracheoles located close to cells so most cells can obtain via diffusion? (1)
Diffusion gradient created so O2 diffuses out into nearby cells
Waxy cuticle on surface prevents water loss via evaporation (1)

I have a selection of questions for the whole topic, in a past paper I have made which has 85 marks and meets various Assessment Objectives. If you would like this, please message me. I haven't compiled the mark scheme yet though
Reply 2
hey, i did this exam in june 2009 and then resat it in january, and so far i don't think anything about the transport of water through plants has come up.. so i'd say that's a definite possibility.
I hate, hate, hate plants. I seriously hope there isn't too much of it :sigh:
they could easily stick plants as one of the 10/15 mark data questions at the end >:frown:
I did the Jan 10 paper as my mock, and antibiotic resistance, meiosis & water transport in plants were all missing from it, so I'm thinking they might come up.
meiosis would be a good one to stick in, not been on yet
Reply 7
Not looking forward to this one. 1 hour 45 minutes aswell.
i know :frown:
plants, meosis, insects, dna hybridisation, immunological comparisons, antibiotics, impact of agriculture and deforestation, all haven't came up
dna, blood vessels, taxonomy, are very common
i think types of vatiation will come up ie. inter and intra specific variation, continuous/discontinuous, and some questions on sampling.
also water movement and gas exchange through plants im sure will come up.
hey_its_nay
plants, meosis, insects, dna hybridisation, immunological comparisons, antibiotics, impact of agriculture and deforestation, all haven't came up
dna, blood vessels, taxonomy, are very common

for the immunological comparisons did you learn the method of it? or just that it is one of the things used to help with realationship within organisms?
Reply 12
I love the plant theory e.g. transpiration, root pressure and cohesion-tension theory.
Stratos
I love the plant theory e.g. transpiration, root pressure and cohesion-tension theory.

me too it's easy marks. didn't get it at first because its dull then i just got down to it and now best bit :smile:
Reply 14
hey does anyone have any biology notes?
Cravez
for the immunological comparisons did you learn the method of it? or just that it is one of the things used to help with realationship within organisms?

yh, they will ask you for the method
Reply 16
Kinesthetic
My tips would be to learn the mark schemes.

If it asks you about dissociation curves - left = higher affin, right = lower affin, for one mark.
Explaining the result e.g releases more o2 into respiring tissues / picks up more in lungs.

They bring in some unit 1 stuff too - remember for enzyme stuff:
Change in hydrogen bonds (1)
results in a change in tertiary structure (1)
substrate cannot bind as active site shape isn't complementary (1)
no enzyme-substrate complexes formed (1)

Also, index diversity is likely to come up so know how to do this.
I'd also suggest learning plant theory too, as this hasn't been featured on the exam yet.

Gas exchange - They could ask you with a diagram, or more simply just recall such as "Give 2 features of gas exchange in fish and explain how it is efficient".
Main points to remember: number in brackets indicate marks given for the content
Fish:
Countercurrent system - oxygen constantly obtained from the gradient created (2) - blood runs against water so O2 is diffused as gradient is steep.
Diffusion gradient or diffusion pathway (1)
Occurs across whole gill - large surface area (1)
Gill filaments/lamellae - large surface area (2)

Insects:
Air enters through spiracles (1) spiracles can open/close - prevents water loss
Trachea branch out into tracheoles for large surface area (2)
- which means tracheoles located close to cells so most cells can obtain via diffusion? (1)
Diffusion gradient created so O2 diffuses out into nearby cells
Waxy cuticle on surface prevents water loss via evaporation (1)

I have a selection of questions for the whole topic, in a past paper I have made which has 85 marks and meets various Assessment Objectives. If you would like this, please message me. I haven't compiled the mark scheme yet though



This sounds really useful! can you send it to me if pos?:smile:

Latest