Chapter 5- Photosynthesis Flashcards
Photosynthesis
Process which collects energy from the sun and brings it into the natural world
Plants as photosynthesizers
Once in plants, energy can be transferred to other organisms
Light E — chemical E— high E foods (carbs)
Chemical representation
CO2 + H2O + sun= glucose and O2
Autotrophs
Self-feeders
Uses inorganic substances (non carbon) to produce organic compounds
All photosynthesizers
Heterotrophs
Consumes preexisting organic compounds
Humans/animals
Chlorophylls
Mostly in plants cells
Absorb most colors, reflect green
Masks other colors
Carotenes
Lesser (accessory) pigments
Absorb violets and blues, reflects red, orange and yellow
Mesophyll cells
Where most photosynthesis occurs
Contains lots of chloroplasts
Granum
Stacks of discs within the chloroplasts
Thylakoids
Each disc in the granum
Thylakoids membrane
Pigment molecules embedded here
Proteins embedded here
2 stages of photosynthetic reactions
Light dependent
Carbon reactions
Light-dependent reaction
Occurs in the thylakoids
Requires sun and H2O
Produces ATP and NADPH
Oxygen in a product
Carbon reactions
Doesn’t require light
Uses CO2, ATP and NADPH
Produces glucose (sugar)
Photo systems
Part of ETCs that convert light E into ATP and NADPH
I and II both absorb light at the same time.
They become photoexcited and e-‘s are stripped from both and travel one ETC
Lost e-‘s from II produce ATP
Lost e-‘s from I are picked up by NADP+ to produce NADPH
