The biochemistry of photosynthesis
General aim of the lesson: Describe the phases of photosynthesis.
Detailed aims: To differentiate between light-dependent and light-independent reactions. To explain
the light-dependent phase. To explain the light-independent phase. To name three phases of the
Calvin cycle.
Assignments:
Symbol
Assignment
BP14
Read the definition of the light phase of photosynthesis and photophosphorylation.
BP15
Watch the film about non-cyclic phosphorylation.
BP16
Watch the film about cyclic phosphorylation.
BP17
Read the definition of the dark phase of photosynthesis.
BP18
Watch the film about the light-independent reaction of photosynthesis.
BP05
Watch the film about the Calvin cycle.
Complete the exercise.
The light phase of photosynthesis is the phase that depends on light. During this phase, light
energy captured by chlorophyll molecules is transformed into chemical energy, which is stored in ATP
and NADPH.
Photophosphorylation is the process by which electrons are energised by photons of light and their
energy is used for the phosphorylation, i.e. the addition of a phosphate group to a protein of ADP in
the synthesis of ATP.
The dark phase of photosynthesis is the light-independent phase, during which ATP formed in the
light phase is used as a source of energy and NADPH is used as a reducing agent in the
transformation of carbon dioxide to sugar.