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Photosynthesis anyone help?

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    https://learning.watfordboys.org/plu...orcedownload=1For 5ci) when you are asked to describe the effect of the increasing light intensity on A, there is one mark for stating that at higher light intensity, there is no effect on the rate of photosynthesis. I think this is refering to the light intensity from 6.25 to 100.00 but there is a slight increase and decrease though...

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    (Original post by coconut64)
    https://learning.watfordboys.org/plu...orcedownload=1For 5ci) when you are asked to describe the effect of the increasing light intensity on A, there is one mark for stating that at higher light intensity, there is no effect on the rate of photosynthesis. I think this is refering to the light intensity from 6.25 to 100.00 but there is a slight increase and decrease though...

    Thanks
    Would you add an attachment to your post instead of a download link, please? Have found this*** picture in the internet to depict the dependence of light intensity on photosynthesis.*

    Up to the highest point, the light intensity increases the rate of photosynthesis. It is just a higher intensity increases the creation of ATP from ADP and NADP to NADPH, that is to say more enegery is building up. The creating of ATP from ATP and NADP to NADPH has a limit what means that photosynthesis is just able to produce a maximum rate of this energy in a certain time, say a minute. It is just the calvin cycle is not able to work faster and more productive, no matter how much the light intensity overruns the maximum of it. I suppose so. * *
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    (Original post by Kallisto)
    Would you add an attachment to your post instead of a download link, please? Have found this*** picture in the internet to depict the dependence of light intensity on photosynthesis.*

    Up to the highest point, the light intensity increases the rate of photosynthesis. It is just a higher intensity increases the creation of ATP from ADP and NADP to NADPH, that is to say more enegery is building up. The creating of ATP from ATP and NADP to NADPH has a limit what means that photosynthesis is just able to produce a maximum rate of this energy in a certain time, say a minute. It is just the calvin cycle is not able to work faster and more productive, no matter how much the light intensity overruns the maximum of it. I suppose so. * *
    Hi, sorry about the link; I have now attached the picture for you. The bit that is highlighted, how does the data show that light intensity has no effect on the rate of photosynthesis when it does fluctuate a little? I understand that at this point the light intensity will not a limiting factor.

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    Distance from lamp is uniformly decreasing but light intensity does not increase proportionately. For small increases in light intensity, the volume of gas produced in A increases greatly. However a threshold seems to be reached at light intensity of 6.25 beyond which despite large increases in light intensity, the volume of gas produced is nearly the same. So compared to initial large jumps in gas produced, the last highlighted values can be considered to remain constant. What this means is that light is not a limiting factor here, in fact it is in excess towards the final readings. So despite reducing the distance from the lamp and increasing light intensity, the volume of gas produced does not exceed a threshold. This also tells us that there could be another limiting factor not mentioned here which is preventing the rate of photosynthesis from crossing that point such as CO2 and water availability. And as mentioned in a post above, there is only so much work or reactions per unit time that can take place within the chloroplast.

    Hope this helps.
 
 
 
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