Biology problem

[HamzaAsghar]

Hey could anyone please help me with the question 7
I even read the examiner report but could not understand

Here's the link

http://www.xtremepapers.me/CIE/Cambridg ... 7_qp_1.pdf

 

[AnGeL.Of.DaRkNeSs]

yar dont make a new thread on every bio question u could have posted this question in this forum viewtopic.php?f=25&t=7724 by silent-hunter which is basically for BIO QUESTIONS....

 

[abdullahsatar]

ummmm can you tell me what year it is? pdf ain't installed on my system..

 

[HamzaAsghar]

yar dont make a new thread on every bio question u could have posted this question in this forum viewtopic.php?f=25&t=7724 by silent-hunter which is basically for BIO QUESTIONS....

Sorry yaar aap you mind her ker gai.

I am new to thus forum tou mujhay nahi pta tha kay aik thread ban chuki hai so will do from next time

 

[HamzaAsghar]

ummmm can you tell me what year it is? pdf ain't installed on my system..

Yaar graph wala sawal hao tou wo paste nahi ho raha idher sorry :no:

 

[OakMoon!]

For this question, you should know the exact value of the normal concentration of CO2 in the atmosphere i.e. 0.04%. According to the graph CO2 is a limiting factor until the concentration incraseas to about 0.1%, after which the temperature becomes a limiting factor. But since, the atmospheric CO2 concentration is less than the 0.1% concentration, CO2 will be a limiting factor at the normal atmoshperic concentration. Hope this cleared your confusion. If you still have a problem in understanding, let me know. I'll elaborate my answer using diagrams.

 

[abcde]

^correct! Some books state the normal (atmospheric) CO2 concentration is 0.03% of the volume of air. So keep these values in mind. Any factor which alters the rate of a process if it's amount is varied is called a limiting factor. The graph shows that if the CO2 conc. is increased above 0.03% or 0.04%, the rate of photosynthesis can increase considerably, thereby making it the limiting factor at normal atmospheric carbon dioxide concentration.

 

[HamzaAsghar]

Thanks both of you

But at 0.04% the graph is increasing na tou doesnt it mean kay rate of photosynthesis is increasing?

 

[OakMoon!]

Yes, limiting factor is a factor that limits the effect of other factors on the rate of reaction, i.e. it limits the reaction. When the graph is increasing, it means that unless the CO2 concentration is increased, the rate of photosynthesis will stay limited. But it is no more a limiting reactant once the rate becomes constants, since and increase in CO2 is not having any effect on the reaction or its not limiting it.