Oxygen is a vital element within cellular respiration. An intrinsic part of the cellular respiration cycle is the transfer or electrons through the electron transport chain, and at the end of it exists the mitochondria, in which electrons are donated to the Oxygen and combine with hydrogen ions to form water.
The electrons needed by photosystem ii originate from water.
X: Ozone layer destruction
Y: Mass extinction
First one is Model and second one is Inference
