photosynthesis Flashcards
what are sunlight, water, and carbon used to?
1) store energy
2) from plant matter
how is energy stored
the chemical bonds of sugars
what is used to generate ATP
energy stored in sugars
what is the photosynthesis equation
6CO2 + 6H20 —> C6H12O6 + 6O2
what does light-dependent regions do
1) captures light energy
2) removal of hydrogen from H2)
3) conversion of light energy into chemical energy (NADPH & ATP)
what does light-independent reaction do
1) storage of chemical energy in sugar
2) reduction of CO2 in the light-dependent region
what is photons
packets of light energy that light travels through
what happens when a photon meets a particle
1) Bounce off the molecule -> reflected
2) Pass through the molecule -> transmitted
3) Be absorbed -> adding energy to the molecule
what happens to pigments on plants
the pigments will absorb the wavelengths in the visible spectrum
what ill energy do in pigments
it will cause one of the electrons within the molecule to be raised to a higher energy level
where does photosynthesis take place?
chloroplasts of eukaryotic cells
where is chlorophyll found
found within thylakoids of chloroplasts
where is chlorophyll also found
the space outside of thylakoids is called stroma
how is free energy captured
by pigments in plants
what colors does chlorophyll absorb?
red and blue
what color is reflected by chlorophyll
green
what are photosystems
light-harvesting complexes where light absorption happens
where are photosystems I and II
embedded in the thylakoid -> internal membrane of cholorplast
what connects the photosystems
Electron Transport Chain
how are electrons energized in Photosystems 1 and 11
chlorophyll absorbs free energy in light
how does the ETC connect the photosystems
connect the transfer of free energy electrons
what happens in thylakoid membrane
light-dependent reactions
what is C3
C3 is used for normal synthesis
what happens to the electron after it is energized?
passed on to an electron acceptor protein
how is the energy used in light-dependent regions?
they pump hydrogen ions across the thylakoid membrane to the interior lumen
what happens in the PS II
1) after the last chlorophyll gives up its electron -> it is very unstable
2) last choloropyll will grab electron from water ( hydrogen and electrons are stripped off)
3) oxygen is released off into atmosphere
4) hydrogen remains in lumen
explain the trend of energy in electrons in PS II and PS I
since H20 is broken apart-> the electrons are very excited and hat goes through Etc and decreased and as light energy strikes, it shoots back up
what is photophosphorylation
using sunlight to power ETC
what happens in PS I
1) the “last chlorophyll” will give up the electron to the “terminal electron acceptor” –> NADP+ will form into NADPH
2) electrons are replenished with electrons from PS II
what enters in photosynthesis
water in light reactions
co2 in calvin cycle
what happens in photophosphorylation
1) hydrogen ions will build up inside the thylakoid when water is split
2) ETC will also pump hydrogen ions across the thylakoid membrane
3) the proton gradient is made and it will make ATP with ATP synthase
what leaves in photosynthesis
o2 in light reactions
sugar ( CH2O) in calvin cycle
where does the calvin cycle take place
within the stroma of the chloroplast
what is used in the Calvin cycle
ATP and NADPH are used to fix CO2 into glucose
what happens to CO2 in the Calvin cycle
it is reduced —> electrons are giving to it -> stripped from AtP and NADPH
what are the sugars used for
- building other carbon compounds
-energy
what does the light reactions give to the calvin cycle
ATP and NADPH
what does the calvin cycle give to the light reactions
NADP+ and ADP + P
how is carbon fixed
uses an enzyme called Rubisco
what are the three steps into fixing carbon
1) carbon fixation
2) reduction
3) regeneration
how do CO2 and O2 love in and out of plants
the stomata can open and close
what is C4
O2 is fixed instead of CO2 in the Calvin cycle
different enzyme is used and not all cells will fix CO2 into sugar
what is the result of using only C4
less sugars are made and less water is needed
what is CAM
when CO2 is taken only at night and stromata is closed during day so less water is needed and less sugar are made
what is the difference in C3 and C4 and CAM pathways
in the C3 pathway -> all of it happens in the same cell
in the C4 and CAM pathway -> different cell used to fix carbon
what enzyme is used in C4 and CAM
PEP carboxylase
what plants use C3
80% of all plants
what uses C4
corn, sugar cane, most dry grasses
what uses CAM
pinapple and cactus
