Edexcel GCE Biology Unit 5 6BI05 June 2013

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Quick question: What would happen if the temperature increases during the Respirometer experiment?

I imagine the rate of respiration would increase due to a faster metabolism of the woodlice, therefore meaning they take in oxygen quicker.

Reply 321

Chris-69

Original post by Selym95

I imagine the rate of respiration would increase due to a faster metabolism of the woodlice, therefore meaning they take in oxygen quicker.

So then the pressure would be lower that it was before the temperature rise and hence the coloured liquid would not travel as far?

Edit: Wouldn't an increase in respiration mean that more oxygen is released by the organism, increasing pressure?

(edited 10 years ago)

Reply 322

Selym95

Original post by Chris-69

It would mean the opposite, aerobic respiration takes in oxygen and produces carbon dioxide as a bi-product.

The liquid would move faster because more oxygen will be taken in by the woodlice, so the fluid would move towards the woodlice faster than usual.

Reply 323

Chris-69

Original post by Selym95

Oh right, yes. Thanks!

Reply 324

bubblegummer

could someone please explain how the transcription factor work? we need to know two different processes which is for peptide and steroid hormones right? thanks in advance.

Reply 325

hayleyvictoria

Original post by Chris-69

What would people say are the advantages and disadvantages of a simple respirometer and u-tube respirometer?

Simple respirometer = Advantages - Very simple to set up; minimal number of connections makes a good seal easier to obtain.
Disadvantages - Doesn't allow you to reset it; it needs a control tube used along side it. No scale, so measurements less likely to be accurate.

U-tube respirometer = Advantages - Does not need to have an additional control as the second tube balances out the effects of changes of temperature or atmospheric pressure. The syringe allows you to move the liquid in the U to reset the apparatus.
Disadvantages - Tendency for connections to leak. Can be expensive.

Hope this helps Chris :smile:

(edited 10 years ago)

Reply 326

kattowell

Hi can anyone please look at question 5c(i) January 2011 paper - link below
http://www.edexcel.com/migrationdocuments/QP%20GCE%20Curriculum%202000/January%202011%20-%20QP/6BI05_01_que_20110127.pdf
and this is the markscheme
http://www.edexcel.com/migrationdocuments/QP%20GCE%20Curriculum%202000/January%202011%20-%20MS/6BI05_01_rms_20110309.pdf

I do not understand this question or the answer, could anyone please explain it to me?
Thanks!

Reply 327

Chris-69

Original post by hayleyvictoria

Thank you!

Reply 328

ItsDatGuy

ive got 3 exams this week :/

Reply 329

rudizzy123

What experiments do we need to be aware of? I can't remember the experiments we did :|

Reply 330

hayleyvictoria

Original post by rudizzy123

What experiments do we need to be aware of? I can't remember the experiments we did :|

As in core practicals?
-Habituation
-Spirometer
-Respirometer

Reply 331

Dhaden

Anyone compiled a list of topics that may come up for the pre release article?

Reply 332

pamella

hey, does anyone have some example questions for the naked mole rats article ? could you please upload it? any suggestions on what is likely to come up? im so stuck on it!

Reply 333

jojo1616

Original post by ItsDatGuy

I can't start any past papers until thursday afternoon :frown:

I'm basically screwed for this exam

Same here, you're not alone

Posted from TSR Mobile

Reply 334

Chris-69

Can anyone tell me if I've got this right?

Respirometer experiment:

Liquid will travel further if:
- temperature of test tube increases --> increase rate of respiration --> greater O2 uptake --> decrease in pressure in the tube --> liquid pushed further along by atmospheric pressure as it takes longer for pressure inside the tube to = pressure outside the tube
- decrease in pressure in test tube ---> liquid pushed further along by atmospheric pressure as it takes longer for pressure inside the tube to = pressure outside the tube
- increase in atmospheric pressure --> liquid pushed further along by atmospheric pressure as it takes longer for pressure inside the tube to = pressure outside the tube

I'm not sure if I'm understanding this :/

(edited 10 years ago)

Reply 335

Lujain Al Omari

Original post by SKK94

In cellular respiration, is 'reduced NAD' written as 'NADH₂' or 'NADH + H⁺' ?
Is either form accepted?

yes

Reply 336

SKK94

Original post by Lujain Al Omari

yes

Thanks

Reply 337

Brad0440

Original post by pamella

hey, does anyone have some example questions for the naked mole rats article ? could you please upload it? any suggestions on what is likely to come up? im so stuck on it!