he put a mint plant in a closed container with a burning candle.
The candle flame used up the oxygen and went out
After 27 days, Priestly was able to relight the candle
This showed that plants produce a gas that allows fuels to burn. This gas is oxygen.
organisms use chemical energy to make larger organic molecules from simple inorganic molecules such as water and carbon dioxide - this is autotrophic nutrition
organisms using light as the energy source for autotrophic nutrition are referred to as 'photoautotrophs'
compensation point
when rate of respiration and photosynthesis are balanced
plants respire all day and photosynthesise only during the day
