This discussion is closed.
fjurble
Badges: 0
#1
Report Thread starter 16 years ago
#1
Hi,

I was going through an exam paper, and came across this question...

"The concentration gradients of oxygen and carbon dioxide are maintained in the lungs during gas exchange. Describe how breathing and circulation achieve this. [5]"

Any pointers on how to answer that for 5 marks?
0
emmz
Badges: 1
Rep:
?
#2
Report 16 years ago
#2
(Original post by fjurble)
Hi,

I was going through an exam paper, and came across this question...

"The concentration gradients of oxygen and carbon dioxide are maintained in the lungs during gas exchange. Describe how breathing and circulation achieve this. [5]"

Any pointers on how to answer that for 5 marks?
breathing achieves it by the lungs reducing the volume - increasing in presure so carbon dioxide is forced out. the muscules then relax increasing the volume so oxygen goes frm an high conc to low conc into the lungs. soz its wot i wud write lol.
circulation - blood goes to the lungs for oxygen and at the same time exchanges it for carbon dioxide and the lungs breath the carbon dioxide out.
0
GH
Badges: 13
Rep:
?
#3
Report 16 years ago
#3
Don't forget the concluding phrase: Thus providing favourable concentration gradients for O2 and CO2 diffusion.
0
Ben.S.
Badges: 2
Rep:
?
#4
Report 16 years ago
#4
(Original post by 2776)
Don't forget the concluding phrase: Thus providing favourable concentration gradients for O2 and CO2 diffusion.
I don't think that answered the question. I reckon it has more to do with ventillation, because the circulatory system braches is parallel with the respiratory tree and the set up is analagous to blood flowing past a continually circulated pool of air - any answer should state how the difference (they call it a 'gradient', but that's a bit of a daft word to use) MAINTAINED, not just how it is set up.

Ben
0
X
new posts
Back
to top
Latest
My Feed

See more of what you like on
The Student Room

You can personalise what you see on TSR. Tell us a little about yourself to get started.

Personalise

Did you get the SQA results you wanted today?

Yes- I did even better than I hoped! (35)
18.13%
Yes- I got what I was hoping for (54)
27.98%
No- my results weren't as good as I'd hoped (104)
53.89%

Watched Threads

View All