RATE OF PHOTOSYNTHESIS

==Light Intensity== [image:http://i.imgur.com/GZy5RsQ.png?1] Increasing light intensity will increase the rate of photosynthesis, but only up to a certain point. Eventually the rate plateaus (levels off) as other factors become limiting (e.g. CO~2~ and water availability). Note that altering the light intensity can also affect the temperature (see below). ==Light Wavelength== [image:http://i.imgur.com/45Z5nrj.png?1] There are actually many different types of chlorophyll, the most common / important of these (chlorophyll a and chlorophyll b) both absorb light most strongly in the red and blue regions of the spectrum. As a result, green light is reflected and the plants appear green. Altering the wavelength can also affect the rate of photosynthesis. For instance, plant growth is poor under green lights as most of the light is reflected. ==Co~2~ Concentration== Increasing CO~2~ will increase the rate of photosynthesis, but only up to a certain point. Eventually the rate plateaus (levels off) as the chloroplasts become saturated with CO~2~ or other factors become limiting (e.g. light intensity). ==Enzyme Activity== Photosynthesis is a series of chemical reactions. Many of these reactions are catalysed by enzymes. Enzyme activity is affected by a range of factors including: *'''pH''' *'''temperature''' *'''enzyme concentration''' *'''substrate concentration''' - the availability of the reactants (Water & Carbon Dioxide) *'''product concentration''' - the build up of products (Oxygen & Glucose) can limit photosynthesis *'''enzyme inhibitors''' ^For further detail see ENZYME ACTIVITY -FACTORS^