Photosynthesis Flashcards
Photoautotrophs
use light energy to synthesize organic compounds.
photosunthesis is a series of what kind or reactions?
redox (gaining energy as it moves forward, endergonic because it requires light energy
what is the flui called within the chloroplasts?
stroma
what are the pores of the chloroplasts called?
stomata
what is grana?
stacks of thylakoids
how does CO2 and O2 enter and exit the chloroplast?
via the stomata
how does water get into the chloroplast?
viens called xylem
what drives photosynthetic reations?
light absorption in the chloroplasts
where does the oxygen gas within photosynthesis come from?
the splitting of 2 water molecules
where does the light reation take place?
in the thylakoid membrane
where does sugar get produced in photosynthesis?
the dark reaction
what are the 3 pigments within the chloroplast and what are their functions?
chlorophyll a: absorb light energy (blue green light)
chlorophyll b: an accessory pigment (olivia green light)
carotenoids: group of accessory pigments (yellow/orange)
what is the least effective light colour?
green because it is reflected so it cannot perform work.
why might a substance show fluorensent light?
fluoresent light is an example of an electron absorbing a photon and reaching an excited state but not utilizing this energy and allowing it to be released as light.
is an electron in an excited state stable?
no
what are the 2 photosystems and which functions first?
photosystem 2 called p680 functions first followed by photosystem 1 called p700
after being excited what is the order the electron is passed through the ETC between complex 2 and complex 1?
plastiquinone, cytochrome complex, plastocyanin
After p700* is formed how do the electrons get passed to NADP+?
through ferrodoxin and NADP+ reductionase
what photosystem does cyclic electron flow use?
photosystem 1 (electron is excitedto p700* but goes backwards through ferrodoxin back to the cytochrome complex, plastocyanin to p700)
what do light reations produce that is used at a reactant in dark reactions?
NADPH and ATP
what is photorespiration?
when temperatures are very high stomata will close resulting in a low intake of CO2 meaning less photosynthetic yield
what are the two cells in a C4 plant?
bundle sheath cell (around the veins of the leaf) and a mesophyll cell (between the bundle sheath cell and the leaf surface)
which cell within the C4 plant does not allow oxygen to enter?
bundle sheath cell (where the calvin cycle takes place)
what is a CAM plants strategy?
stomata are closed during the day but open at night to help conserve water, CO2 is taken in at night and converted to organic acids to be used during the day
