Edexcel GCE Biology Unit 5 6BI05 June 2013

is that the same thing as conduction of an impulse along a neurone ?

how is the volume and rate calculated from the respirometer?

i think so, yeah

Really? And they did am international version because....reasons?

Anyway, thanks a lot for pointing that out for me.

i say:

- impulse arrives at the neurone
- na+ ion channels open atthe region of the neurone and na+ ions flow in ... casuing depolariastion of this part of the membrane
- some of the na + ions move side ways to the next region of the membrane ..... this cause the na+ ion channels in this areas/ region of the membrane to open and so there is an influx of na+ ions into the axon here too
- the same thing occurs again at the next (3rd) region
at the 1st region, the na+ ions close and k + ions flow into the axon ... and the rest of the impulse cyle occurs ... it then goes into refractionary period ....

- the impulse moves away from regions of the membrane in refreactionary period
- in this way the impulse is passed along the neurone



sorry if this is confusing

thats great! Thanks

i just hope such a question does not come up((

how is everyone finding the pre-release? Am getting worried as it has 30 marks!

haha yeah same ... i doubt it's come up that detailed if at all ... far too much


also does anyone know what the process of gene therapy is? ... a quick review please

Breathing rate is the number of peaks (on the trace) x minute
Tidal volume = volume breathed in and out at one breath - from the trace it is top reading (of the peak) minuse the botoom reading of that peak.

from what i remember, is when a gene coding for a desired protein is inserted into human DNA using viral or lipid vectors, so that translation of proteins can start...

something of that kind..hah)

the respirometer is the woodlice in the test tube

sorry i dont... i only know edexcel papers can be found on the edexcel website ^ ^^^


also does anyone know what we need to know about the crutiate ligament thing ?

"Explain how medical technology, including the use of keyhole
surgery and prostheses, is enabling those with injuries and
disabilities to participate in sports, eg cruciate ligaments
repair using keyhole surgery and knee joint replacement
using prosthetics" this is from the spec... I think just what is it and why/shen you use it...

oh damn, you're right.
sorry..

for the woodlice it is:

the volume: at the start mark the level of the liquid in the tube -> after some time measure the distance travelled by the liquid and from there find a volume (pi x r^2 x distancе moved, where r=radius of the tube). Alternatively, the tube can already have volume marks on it - then just read the volume mark. This would be the volume oxygen uptake.

I am not sure you can measure the rate...

Sorry for the mistake before)
Hope this helps

Hey

Hi guys ... does anyone know if it is true that respiration totally stops in the presence of no oxygen? only the hdizzle document says so :?
i though anaerobic resp would take place but it says otherwise ...