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BIOL4 Biology Unit 4 Exam - 13th June 2011

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Reply 560
Original post by SK-mar
i reckonnnnn it will be squirrels.... its always some kind of small furry wild animal... although i like squirrels so i hope its not... haha :smile:


I dunno, last time it was a wood louse :P Not particularly furry ^ ^
Original post by SK-mar
it tells you in the question that the maximum age is something like 95.... so you find the percentage of the age at the specific amount... i think its 85% right??? but then you take 85% of 95 or whatever the maximum age is and it gets you the answer.


AM struggling on 2b :wink:
Reply 562
How is the chloroplast adapted to its function? lets do Q and A...
Wasnt the animals in the Jan11 paper cattle? Theyre not so small and furry.
Reply 564
What do we think the long answers are going to be at the end? Eutrophication and what else?
Original post by Rickesh
What do we think the long answers are going to be at the end? Eutrophication and what else?


Respiration, maybe?
I've seen both parts of photosynthesis on the long answers in past papers but not any respiration yet (I think)
Reply 566
Original post by InfinitelyVixey
Respiration, maybe?
I've seen both parts of photosynthesis on the long answers in past papers but not any respiration yet (I think)


Have you got the mark scheme for the photosynthesis one? That might come up?
Reply 567
Original post by arvin_infinity
AM struggling on 2b :wink:


This is how i did it:

The max rate will be steepest point on graph so get any 2 points on the steepest bit and just read off the graph


25-20= 5

400-200=200

200/5 = 40.. do u get it? Hope it helps..
Reply 568
Original post by Rickesh
How is the chloroplast adapted to its function? lets do Q and A...


intergranal lamelae increases SA for light dependant reaction, Thylakoids are stacked up in granum for maximum rate of light dependant photosynthesis.
Reply 569
Original post by Stratos
intergranal lamelae increases SA for light dependant reaction, Thylakoids are stacked up in granum for maximum rate of light dependant photosynthesis.


yep your turn to ask
Original post by *Rainbow*
This is how i did it:

The max rate will be steepest point on graph so get any 2 points on the steepest bit and just read off the graph


25-20= 5

400-200=200

200/5 = 40.. do u get it? Hope it helps..


I get it now..but we meant to draw a line that crosses x-axis and then read off the graph

(thats what we do in physics and chemistry)
Reply 571
Original post by arvin_infinity
I get it now..but we meant to draw a line that crosses x-axis and then read off the graph

(thats what we do in physics and chemistry)


like a gradient?
Reply 572
Original post by arvin_infinity
I get it now..but we meant to draw a line that crosses x-axis and then read off the graph

(thats what we do in physics and chemistry)


Doing that would help yeah :smile:
Original post by Rickesh
How is the chloroplast adapted to its function? lets do Q and A...


1. Contains both Dna and ribosome so it can manufacture protein needed quickly and easily

2. Protein structure hold chloroplast in a precise manner that allow max aborption of light

..
Reply 574
Original post by arvin_infinity
1. Contains both Dna and ribosome so it can manufacture protein needed quickly and easily

2. Protein structure hold chloroplast in a precise manner that allow max aborption of light

..


yep..your turn to ask...
Original post by Rickesh
like a gradient?


Yeh..but u would get a different answer!! (wrong answer to be precise:P)
Energy is transferred through an ecosystem. Describe how and explain why the efficiency of energy transfer is different at different stages in the transfer. (6 marks)
Reply 577
Original post by arvin_infinity
Yeh..but u would get a different answer!! (wrong answer to be precise:P)


when working out the gradient? Why?
Original post by Rickesh
Have you got the mark scheme for the photosynthesis one? That might come up?


I haven't got them to hand but I know they're on the AQA website
Reply 579
Original post by arvin_infinity
Energy is transferred through an ecosystem. Describe how and explain why the efficiency of energy transfer is different at different stages in the transfer. (6 marks)


When light hits the producer (plant) not all of it is absorbed by the plant as some of it is lost as heat, or is reflected or even it may not be the right wavelength. When the energy is transferred through different stages of the trophic levels, the energy efficiency decreases, as some of it is lost during respiration or in the faeces- as some parts of an organism is not digestible e.g. cellulose. Alternatively some organisms use the energy for growth and repair. Urmm what else is there ?? Thats not enough for 6 marks is it? How many would i get?

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