How do plants do it?
Factors that affect Photosynthesis
Light, Carbon Dioxide and
Temperature
1. Light intensity: as light increases, rate of
photosynthesis increases
By
Godfrey Dzhivhuho
Ever defined what a plant is?
Stages of Photosynthesis
2. Carbon Dioxide: As CO2 increases, rate of
photosynthesis increases
Plants are Autotrophs or Producers, these are organisms that
have the ability to produce their own food.
They do this by process known as Photosynthesis, a process
in which plants produce their own food using:
Energy from the sun
Water
Carbon Dioxide
Chlorophyll
3. Temperature: The low the Temperature =The
low Rate of photosynthesis
4. Temperature Increases = Rate of
photosynthesis increases f temperature too
hot, rate drops
6CO2 + 6H2O + energy  C6H12O6 + 6O2
Foxey Question… why are leave green
(which reflects away green light) and
not black (which absorbs all light)?
Oxygen catastrophes/ GOE
Cyanobacteria produced oxygen (3 ga)
Captured by dissolved iron organic matter
(sinks)
Became Saturated and started to
accumulate in the atmosphere
Was toxic to life at first (anaerobic)
Rising of O2 in the atmosphere caused
extinction of Earth’s anaerobic inhabitants.
Gave rise to evolved organisms that used
oxygen for life
Banded Iron Formation by
Oxygen