Learning Outcomes State the meaning of the term ‘limiting factors’ State 3 limiting factors State the effect these limiting factors have on the rate of photosynthesis

How does NO / LITTLE / A LOT of light affect photosynthesis?

Limiting factors How many loaves of bread can baker A make? 1000 g = 1Kg Limiting factors How many loaves of bread can baker A make? Why can baker A not make more than this? How many loaves of bread can baker B make? Why can baker B not make more than this? What do you think we mean by a ‘limiting factor’? 2 Not enough fat 3 Not enough sugar

Limiting factors A limiting factor of photosynthesis is a factor that decreases the rate of photosynthesis There are 3 limiting factors: Light intensity Carbon dioxide concentration Temperature If any of these 3 factors are limited, then photosynthesis cannot take place

THINK / PAIR / SHARE What are the products of photosynthesis? How could A LOT OF LIGHT affect the rate of oxygen production? How could A LOT OF LIGHT affect the rate of starch production? What do you think would happen to the mass of the plant? How could VERY LITTLE LIGHT affect the rate of oxygen production? How could VERY LITTLE LIGHT affect the rate of starch production?

What happens to the SIZE of the plant after photosynthesis and WHY? When plants photosynthesise, they make glucose sugar and store it as starch. When they store the starch, the plants get bigger and heavier (THE MASS INCREASES) 

Plant growth If a plant receives a lot of light: the rate of photosynthesis would … Starch production would … The growth rate of the plant would … If a plant receives a limited supply of light: We can overcome this limiting factor by… By overcoming this limiting factor, ______________ would once again increase!

Plant growth Plants will also react the same way with carbon dioxide and temperature as they do with light.

Limiting Factor Problem Solving Qs Very tough Qs – only your smart cookies will be able to do this without support! a) How many units of sugar will plant A be able to make? b) Which factor is in short supply and is holding up plant A’s photosynthesis? c) Which plant will be able to make the greatest number of sugar units? d) If plant E is given an unlimited supply of light energy, how many units of sugar will it be able to make under the conditions given?