Download photosynthesis

PHOTOSYNTHESIS
(Part 1)
The Basic Facts
• It is the conversion of light energy
into chemical potential energy.
• The energy is stored in organic
molecules (e.g. ATP and glucose)
• Carbon dioxide is reduced to
produce carbohydrate
• So, it needs a supply of electrons
hydrogens and energy!
Light dependent
stage
(on thylakoid
membranes)
• The aim is to produce a supply of
ATP (energy) and electrons that can
be used to reduce carbon dioxide.
• The electrons are carried by NADP
(called reduced NADP or NADPH
when it is carrying electrons).
• Oxygen is released as a waste
product.
Or put a different way…
NADP
water
NADPH
light
dependent
reaction
ADP + P
ATP
oxygen
This is a blank slide for Mr King to do his own drawing on
Photolysis
• Using light energy to split water into
electrons, hydrogen ions and water.
• H2O  H+ + e- + O2
• Replacing the electrons and hydrogen
ions now carried by NADPH
summary
• Chlorophyll absorbs light energy and
its electrons are ‘excited’
• ‘excited’ electrons pass through a
series of carriers releasing energy
to generate ATP from ADP and P
(photophosphorylation)
• Electrons are picked up by NADP
• Light energy splits water and the
electrons are used to replace
missing electrons in chlorophyll
• This all happens on membranes.
The light dependent reaction takes place on the...
This is so that...
The reaction needs ...., ...., .... and ....
The reaction produces .... and ...
.... is also produced.
The ... and ...pass into the ... for the second stage in
photosynthesis.