Photorespiration Flashcards
Photorespiration is due to the
Divergence from the Calvin Cycle due to RuBisCo picking up O2 instead of CO2
Photorespiration leads to the
Loss of an already fixed carbon into CO2
Why is photorespiration bad?
It wastes energy and decreases sugar synthesis
Photorespiration is caused by which situations?
More hot + dry
Photorespiration begins in the chloroplast when
RuBisCo attaches O2 to RuBP
What is the product when RuBisCo attaches O2 to RuBP?
3-PGA + phosphoglycolate
What part of the leaf allows for air to enter the cell and water vapors to leave?
Stomata
Photosynthetic process happens in the
Mesophyll
C4 Plants have evolved past photorespiration by
Fixing carbons in cells exposed to air and later pumping the 4C molecule in leaf not exposed to O2
First carbon fixation in C4 plants results in the formation of
A 4C molecule called Oxaloacetate
Oxaloacetate further gets converted into either
Malate or Aspartate, which will react to produce CO2 + PEP
PEP Carboxylase is an enzyme that can only fix
Carbon dioxide
Malate gets transferred into bundle-sheath cells via
Plasmodesmata
CAM Plants are
Desert plants, which keep stomata closed during the day
How do CAM plants photosynthesize?
By keeping stomata open at night, fixing CO2 at night