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Nutrition

           Atmospheric carbon dioxide concentration   minerals  and  gases as  well  as products
           The average concentration of carbon dioxiode  of photosynthesis. Shortage of water
           in the atmosphere is about 0.03%. As the  leads to wilting of plant leaves, which in
           concentration of carbon dioxide increases   turn causes closing of the  stomata. This
           from the average value, it also increases the   results  into  a  reduced  diffusion  rate  of
           rate of photosynthesis. Carbon dioxide is   carbon dioxide into  the  chloroplast,  and
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           required in light independent reactions, but   hence a decreased rate of photosynthesis.
           the concentration above 0.1% can damage    Additionally, water shortage causes cells to
           the plant leaves. On the other hand, low   become flaccid; thus, they cannot function
           levels of carbon dioxide tend to limit the rate
           of photosynthesis. It should be noted that,   well and this affects the translocation of
           C  plants are affected by low concentration   synthesised products.
             3
           of carbon dioxide in the atmosphere, while   Light
           C  plants are efficient in utilising carbon
             4
           dioxide  even  when the  concentration  of   Task 5.8
           carbon dioxide in the atmosphere is low.    Search  from  the  internet  sources  on
                                                       simulations  on the effects of light
           Temperature                                 intensity and carbon concentration on the
           Within the optimum range of temperature,    rate of photosynthesis and then prepare
           the rate of photosynthesis tends to double   short notes.
           for every 10  C rise of temperature. For
                         o
           example,  the optimum temperature  for     The effect of light on the rate of photosynthesis
           plants that survive in temperate climates   can be described on the basis of its quality
           is 25  C.  The  temperature  above 35  C   (light wavelength) and quantity (light
                 o
                                                 o
           usually causes denaturation  of enzymes    intensity).
           catalysing photosynthesis in both, dark and  Light quality (wavelength of colours):
           light reactions. This will lead to slowing  Photosynthesis usually occurs when green
           down or stopping of the  photosynthesis  plants absorb light within a limit of visible
           process. In low temperature, such as below  light spectrum. The most effective range
           10  C, enzymes catalysing photosynthesis   is within a red-orange band (600nm-700 nm)
              o
           become inactive, hence lowering its rate.  and a blue-violet band (400nm-500 nm).
                                                      The central  band is also effective,  but
           Nutrients supply (availability of nutrients)  less than others because the chlorophyll
           Minerals, such as magnesium and nitrogen,  molecules  show very little  absorption
           are components of chlorophyll. Deficiency  of light in this region. Maximum light
           of these minerals reduces the rate of      absorption corresponds to the maximum
           photosynthesis  because  the  plant  lacks   rate of photosynthesis.
           enough chlorophyll molecules for trapping   Light intensity: The rate of photosynthesis
           enough light energy.                       varies proportionally to light intensity.
                                                      However, at a certain point called light
           Water availability                         saturation point, the rate of photosynthesis
           Water is one of the essential raw materials   reaches its maximum and therefore attains
           for photosynthesis. It also plays other roles   constancy. Any  further  increase  in  light
           in the plant body, such as translocation of

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