Limiting Factors

Describe the graph for light intensity

As the light intensity increases the rate of photosynthesis increases steadily but onto at a certain point

-As the line starts to bend light intensity is the limiting factor so limits the rate of photosynthesis increases steadily

-when the line is straight light intensity isn’t the limiting factor, it’s either temperature or co2 levels

Describe the carbon dioxide concentration graph

-As the concentration of co2 increases the rate of photosynthesis also increases

-After this the graph flattens out so rate no longer increases. This shows us that Co2 is no longer the limiting factor. This means light intensity or temperature is limiting factor

Describe the graph

-Usually if the temperature is limiting factor its because it’s too low -the enzymes needed for photosynthesis work more slowly at low temperatures

-If plant get too hot the enzymes it needs for photosynthesis gets damaged

-This happens at about 45C

Describe this graph

-The graph shows how rate of photosynthesis is affected by light intensity and temperature

-At the start both lines show that as light intensity increases the rate of photosynthesis also increases steadily

-But the lines level off when the light is no longer the limiting factor. The lines level off at 25 levels off at a high point than the one at 15. Showing that temperature is limiting factor at 15

What’s the inverse square law and what’s its equation

If you halve the distance the light intensity will be four times greater.

Equation is 1/d2

Why do farmers want to increase rate of photosynthesis

As this increases the yield of crops they produce

How do farmers increase rate of photosynthesis

They light and heat their greenhouses. They also add extra carbon dioxide

-Light is added with artificial lights once sun goes down

-Heat is added with heaters when it’s winter or to keep temperature ideal

-If it’s too hot they use shades and ventilation

-They increase co2 by using paraffin heater as it burns it creates co2

What’s the problem of increasing rate of photosynthesis

-Sorting all of this cost money. So farmers have to make sure their cost are justified by increasing yield.