During low light intensities the rate if light dependent reactions decreases

During low light intensities the rate if light

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limiting factor in this situation is light intensity. During low light intensities, the rate if light- dependent reactions decreases and vice versa when the intensity of light is high. The main sites of photosynthesis are the leaves of a plant, where a great quantity of photons reside on the leaf, resulting in a greater number of chlorophyll molecules that are ionized (Urry et al. 2018, p. 145). When the amount of light entering, or light intensity, is increased the rate of reactions of photosynthesis also speeds up and thus the overall photochemical reaction is increased. From the data obtained in this experiment, it is observed that the further away from the light source or if the light source is being prevented from entering a plant when undergoing certain conditions, the rate of light absorption decreases and consequently the rate of photochemical reactions of photosynthesis is reduced. Although most of the results achieve were expected, the control was assumed to be standard throughout the whole experiment, yet an increasing trend was observed for one minute. This could be due to the contamination of other chemical substances.
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SLE132 Biology form and function T2 2019 Assessment Practical 4 Extension What do you think would happened to the change in absorbance of an experimental system (assume that it is the same set up as in the prac) if a compound was added to the assay which absorbed the electrons originating from the special pair of photosystems II? Assume that the system continues to absorb light, evolve oxygen and that the compound does not saturate. Two sentences (50 words or less) would be enough to answer this question. Justify your answer by explaining what happens to the components of the system. (3 marks) YOU MUST NOT DELETE ANY TEXT FROM THE WORKSHEET TEMPLATE, HOWEVER IT IS ACCEPTABLE TO ADJUST THE SIZE OF THE ANSWER BOXES A compound absorbing electrons directly from the photosystem II would be unable to transport these electrons along the chain in order to react with DCPIP and therefore DCPIPH2 would not be produced. When this occurs, the solution would remain blue and the rate of light absorbance would continue to remain the same.
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SLE132 Biology form and function T2 2019 Assessment Practical 4 Reference list Deakin University, 2018, SLE132 Biology: Form and Function (PRACTICAL MANUAL), School of Life and Environmental Sciences. Urry, L, Wasserman, S, Cain, M, Campbell, N, Reece, J, Minorsky, P & Meyers, N 2018, Campbell Biology . 11th edn, Pearson Australia Group Pty Ltd, Melbourne. YOU MUST NOT DELETE ANY TEXT FROM THE WORKSHEET TEMPLATE, HOWEVER IT IS ACCEPTABLE TO ADJUST THE SIZE OF THE ANSWER BOXES
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