Investigating The Activity Of Dehydrogenase In Chloroplasts Flashcards
In photosystem 1 during the light dependant stage of photosynthesis what does NADP act as
An electron acceptor and is reduced. The reaction is catalysed by a dehydrogenase enzyme
How can the activity of a dehydrogenase enzyme be investigated
By adding a redox indicator dye to extracts of chloroplasts.
Like NADP the dye acts as an electron acceptor and gets reduced by the dehydrogenase in the chloroplasts
As the dye gets reduced you’ll see a colour change. For example the dye DCPIP changes from blue to colourless when it gets reduced
How can you measure the rate of the dehydrogenase activity
By measuring the rate at which DCPIP loses colour. To do this you need a colorimeter. A colorimeter measures how much light solution absorbs when a light is shine directly through it
A coloured solution absorbs more light than a colourless one
What does the experiment of investigating the activity of dehydrogenase in chloroplasts show
How to investigate the effect of light intensity on dehydrogenase activity in extracts of chloroplasts
What does the experiment use as a light source
A bench lamp and involves placing tubes of chloroplast extract mixed with DCPIP at a range of different distances from the light source
Light intensity should decrease with increasing distance from the lamp
You must choose the distances you are going to investigate.
