Transcript Photosyntesis

Photosyntesis
What is photosynthesis?
The ability to use light to convert inorganic molecules into organic
molecules.
H2O + CO2 ==== light == sugar + O2
Sugar can then be used to make other required molecules, or it can be
Broken down as a source of energy… O2 is simply a biproduct of photoSynthesis… almost all the O2 in the earth’s atmosphere comes from phot
Synthesis.
Photosyntesis
Leaves and Chloroplasts are adaptations for photosynthesis.
Photosyntesis – light and dark reactions
Photosynthesis has two phases:
A light dependent reaction where the energy in light is converted into
chemical energy of molecules such as ATP and NADPH.
A dark reaction where the molecular energy carriers are used to
build the sugar molecules.
Photosyntesis – Pigments
The first step of photosynthesis involves using pigments to capture light.
The range of visible light used for
photosynthesis is from about
400 to 750 nanometer wavelengths
of electromagnetic radiation…
this range is referred to as PAR –
Photosynthetically Active Radiation.
Although chlorophyll is the primary
pigment used by plants (it’s what makes
plants green…), other pigments such as
carotenoids and phycocyanin are also
used… why do you think this is?
Photosyntesis – Effects of varying light levels
P: photosynthesis
Pmax: maximum photosynthesis
Pg : gross photosynthesis
Pn : net photosynthesis
R : respiration
IK : saturating irradiance
Respiration
Photosynthesis:
H2O + CO2 ==== light == glucose (sugar) + O2
Complete glucose metabolism through cellular respiration:
sugar + O2 ====== H2O + CO2 + chemical and heat energy
Respiration – summary
Respiration – Glycolysis
Respiration – summary
Respiration – lactate and alcohol fermentation
Respiration
NADH:
Nicotinamide adenine
dinucleotide
FADH2:
Flavin adenine
dinucleotide
Respiration – electron transport chain
Respiration – electron transport chain
Respiration – electron transport chain
Respiration - summary
Respiration – other organics besides sugars?