Ch 11 Photosynthesis Flashcards
Word and chemical equation
6CO2+6H2O–>C6H12O6 +6O2
Carbon dioxide + water –> glucose and oxygen
Location Source of -light -co2 -water
Chloroplasts
Sun
Air/ respiration
Enters plant through root, travels up stem
Products and their fate
O2 + Glucose
Fate ofO2
Used by plant or respiration
Passes out of plant through stomata
Fate of Glucose
Respites
Stored as starch
Importance of photosynthesis
Provides food
Provides O2
Reduces levels of CO2
Summary of photosynthesis
Light is absorbed
Water is spilt
Hydrogen combined with co2 to make glucose
Oxygen is released as a by product
1) light is absorbed
Light is trapped by chlorophyll
Provides energy to make glucose
2) water is spilt
Light energy is used to spilt H2O into
-oxygen gas
-protons
-electrons
\+ _
2H2O-->4H + 4e +O23)Light energises electrons
Electrons pass to chlorophyll to become energise
This changes them into high energy electrons
4)Glucose is formed
High energy electrons and protons from proton pool are combined with co2 to form glucose
Light stage
Requires light
Location: grana
Chlorophyll made up of pigments
Pigments arranged in funnel shaped photo systems
Pigments absorb light energy and transfer to the chlorophyll
Chlorophyll absorbs them-> become high energy electrons
They pass to electron acceptor
Light stage pathway 1
Electrons picked up by acceptor, passed through carriers back to chorolopgyl lose energy
Light stage pathway 2
H2O spilt protons to proton pool, NADP- formed electrons picked up by acceptor passed through carriers ATP produced
non cyclic photophosphroylation
Electrons that return to chlorophyll are not the original
End products of light stage
ATP-> provides energy for dark stage
NADPH-> provides protons + high energy electrons
O2-> used for respiration
Dark stage
Location:stroma
Does not need light, can happen in light
Controlled by enzymes
CO2 from air enters chloroplasts combined with protons + electrons to form glucose
