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A level Biology: Post your doubts here!
- Thread starter XPFMember
- Start date
Metallic9896 are you able to manage time? I tend to complete the paper exactly on time.. And tomorrow we also have to shade, so i am really scared on the time part : p
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Good luck tomorrow guys <3 Hope you do well
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Alright, my turn to ask questions. This question is all over the page so taking two screenshots. 
Okay I got rid of A cause I know that capillaries have the highest "total" cross sectional area (for increased diffusion). I got rid of B for the same reason.
Now to C and D. Both have the same cross sectional area graph so that's out of the window. Both also show similar trends in everything else too so it's the actual shapes of the graphs that we need to know, which is insane, at least to me. So how do I know which one is correct?
Okay I got rid of A cause I know that capillaries have the highest "total" cross sectional area (for increased diffusion). I got rid of B for the same reason.
Now to C and D. Both have the same cross sectional area graph so that's out of the window. Both also show similar trends in everything else too so it's the actual shapes of the graphs that we need to know, which is insane, at least to me. So how do I know which one is correct?
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Don't worry about it it'll be the opposite tomorrow. I never timed myself at home but always manage to do it in time with time left for revision. Only in Chemistry do I finish exactly on time in the paper itself. If you manage exactly on time right now I can assure you you'll be done by 50 minutes max.
Is it D..?
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Can't be sure about the exact order but heaviest here I assume is directly related to the relative sizes. The heaviest will probably be the nucleus, followed by chloroplasts (but not here since this is an animal cell), then mitochondrion, and so on. D is a ribosome, and you would know that the smallest (and subsequently, lightest) is the ribosome. A is a lysosome which is small enough, but ribosomes are smaller. B is mitochondrion and C is nucleus, both of which are enormous compared to A and D. So it's A vs D, and you know lysozomes are the packets of hydrolytic enzymes while ribosomes are what make up the enzymes and in all diagrams we see them as much smaller compared to the protein strand that they make. So yeah. XD
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I looked at "wall thickness".. C shows them to be very similar... while veins are relatively a lot thinner, compared to arteries. I also don't understand the other graphs "Exactly", But C can also be rejected, as it shows arteries/arterioles to have similar pressures, which is totally wrong as pressure decreases as blood travels further from aortaYeah it is, but why?
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Okay, so next comes velocity and it decreases upto capillaries and increases when it comes to veins because of muscle contraction the velocity increases.
So answer should be D
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But it's not
That's what I thought too but it's D so darks's (darks' .. ? XD where do I put the apostrophe hmm they say Stevens' or Stevens's, I'll go with darks') explanation seems to be correct.
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Wrong letter lolBut it's not
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We did kind of the same question it was in an o/n series
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I looked at "wall thickness".. C shows them to be very similar... while veins are relatively a lot thinner, compared to arteries. I also don't understand the other graphs "Exactly", But C can also be rejected, as it shows arteries/arterioles to have similar pressures, which is totally wrong as pressure decreases as blood travels further from aorta
Nice going man the point about pressure makes great sense.
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Oh lol okay great then. Thanks a lot guys. Will drop off more if I come across any.
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As for this question:
At the bottom: Nucleus
Then (upwards) : Chloroplasts ,Mitcohondria
Then: RER and SER
Then Ribosomes at the top
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I have a feeling that tomorrow there will be completely new questions considering our paper 4
considering our paper 4- Messages
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I have a feeling that tomorrow there will be completely new questions
Shushhhh :'(
What I don't understand is why Venules have such high cross sectional area ._.Oh lol okay great then. Thanks a lot guys. Will drop off more if I come across any.