The Student Room Group

Scroll to see replies

Reply 3200
Original post by Sheldon Cooper10
are you saying they overlap because they both contain the no 12? but if it was 11-12 and 12-18 there wouldn't be an overlap and therefore the difference between the means is greater and therefore more variation? does this mean the bigger the difference in the range of values obtained from the SD that theres more variation?


if they are both 12, that may be treated as overlap aswell

the key idea, is that if they do overlap, we say the difference maybe due to chance
Reply 3201
Original post by Micheal123456
What's root pressure? And can you run through magnification ; like how to convert certain units


root pressure is the pressure generated when the root absorbs water into the xylem. this applies slight pressure on the column of water, so minimally helps in pushing up the column of water.

maginification:

remember AIM
Magnification = image/actual

and 1 mm = 1000 micrometres
thats all you need to know
Reply 3202

for those doing the exam, balance revision with the sleep needed, you dont want to be battered for the exam, anyone needs anymore help, just let me know
[QUOTE="saaaarn;42933831"]
Original post by Sabby888
I know!!! STRESS!!!

Still going over beta-glucose... should NOT be doing this at this time. But hey ho, I'm probably gonna pull an all-nighter

I know... Think I'm gonna get some sleep and wake up at 6 or I feel I may fall asleep whilst doing the exam :P have you done all the past papers? Try and get some sleep if you can :smile:


No, stupidly I haven't... Had loads of exams this summer... stupid AS resits... I actually think I'm gonna have to go and resit Year 13... well not all my A-level subjects since some of them are fine, guaranteed A's shall we say :biggrin: but Biology I don't think I'm gonna get any higher than a D...

:frown:

Damn my procastrination <<-- sorry I've never known how to spell that word

You??
Original post by oak12

for those doing the exam, balance revision with the sleep needed, you dont want to be battered for the exam, anyone needs anymore help, just let me know


There are still parts of the spec I need to go over, i.e. last two topics, ARGHHH!!

Go to sleep now or stay up and revise???

:confused::confused::confused:

I'm torn
Reply 3205
im outsie guys, in a bit
Reply 3206
how do you know when to say diffusion, when to say concentration and when to say water potential when dealing with gradients and stuff? it seems to change with every question!


Posted from TSR Mobile
Original post by Arllna
how do you know when to say diffusion, when to say concentration and when to say water potential when dealing with gradients and stuff? it seems to change with every question!


Posted from TSR Mobile


Concentration = ions or gases in gas exchange
Gradient = concentrations of molecules or ions being transport from high to low (diffusion) or low to high (active transport).
Water potential - things involving plants such as roots absorbing moisture (high to low) - osmosis.
Do the bases on a DNA molecule contain nitrogen or is that somewhere else?
Original post by KaranbirBandesha
Do the bases on a DNA molecule contain nitrogen or is that somewhere else?

Correct; and a pentose sugar and phosphate group.



Posted from TSR Mobile
3 BIG TIPS guys;

1. Do NOT go into that exam hungry!
2. Take a bottle of water with you
3. Do not go into that exam tired!

Oh yeah, make sure you don't forget rulers and calculators!
(edited 10 years ago)
Reply 3211
Thank you, in transpiration , does water diffuse into air spaces and evaporate from stomata ??


Posted from TSR Mobile
Reply 3212
Original post by Dead End Street
Correct; and a pentose sugar and phosphate group.



Posted from TSR Mobile


I think I wrote pentose sugar in one of the papers but the mark scheme said deoxyribose sugar (Not sure but maybe the june 2012 paper)
Original post by Arllna
Thank you, in transpiration , does water diffuse into air spaces and evaporate from stomata ??


Posted from TSR Mobile


It evaporates, diffusion is just in gases. :smile:
Original post by Arllna
Thank you, in transpiration , does water diffuse into air spaces and evaporate from stomata ??


Posted from TSR Mobile


Water DOES NOT diffuse - only goes through osmosis!
Good luck to everyone today :smile:

Posted from TSR Mobile
Reply 3216
Good luck everyone, I'm sure you will all do fine!
For meiosis, during replication, each chromatid replicated to form a chromosome, so there's a pair of homologous chromosomes?
Original post by Tee Logan x
For meiosis, during replication, each chromatid replicated to form a chromosome, so there's a pair of homologous chromosomes?


Yes there is, in meiosis 1. :smile:
Original post by Nav_Mallhi
Yes there is, in meiosis 1. :smile:


Thank you :smile: so basically in meiosis, homologous pairs line up alongside each other but in mitosis, there are no homologous pairs, all chromosomes just line up at the equator?

Latest