Photosynthesis Flashcards
LDR?
- photosynthetic pigments e.g. chlorophyll a absorb light energy
- excite electron which leaves chlorophyll (photoionisation)
- electrons at higher energy level
- electrons move along ETC
- electrons release energy
- energy used to join ADP and Pi = ATP
- NADP reduced = NADPH
- photolysis of water = H+, electrons and oxygen
formula?
6CO2 + 6H20 + energy —> C6H1206 + 602
where does LDR take place?
thylakoid membrane
what does LDR use?
- light energy
- to make ATP and NADPH
what does LIDR use?
- products of LDR
- to make useful organic comp
where does LIDR take place?
stroma
define organic?
compound that contains carbon
define inorganic?
compound that doesnt contain carbon
what are coenzymes?
non-protein molecules that help enzymes to work by transferring other mol around
coenzymes in photosynthesis?
NADP
- transfers H mol around
define phoshporylation?
adding phosphate group
define photophosphorylation?
using light energy to add phosphate
define photolysis?
using light energy to split molecules
define ETC?
when electrons flow through proteins in membrane
what does the chloroplast do?
absorbs light energy used for photosynthesis to make useful organic comp
TK
- has high surface area
- inc rate of photosynthesis
what are grana?
stacks of TK
light intensity
- higher light intensity
- more energy for LDR
- faster rate of photosynthesis
(needs to be at right WL)
why do plants/ chloroplasts look green?
- reflect green light
- absorb blue and red
- diff pigments absorb diff WL
how limiting factor of light overcome?
- use lamp at night
- glasshouse allows light through
CO2 conc
- daytime = limiting factor
- optimum = 0.4 %
- above - rate of photosynthesis slows
how limiting factor of co2 overcome?
- burn propane in greenhouse
- inc CO2 conc
temp
- photosynth controlled by enzymes
- inc temp - inc rate of reaction
- beyond optimum - rate dec
- high temp causes stomata to close
- less CO2 - dec rate of calvin cycle
how limiting factor of temp overcome?
- burner inc temp
- greenhouse traps warm air
- heating / cooling mantains optimum temp
LIDR?
- CO2 combines with RuBP catalysed by enzyme rubisco
- makes 2 mol of GP
- both mol of GP reduced to form 2 TP (using 2 NADP and 2 ATP)
- most TP regenerated to form RuBP - using energy from ATP
- some of TP converted into useful organic sub
define calvin cycle
uses products of light dependent reaction (ATP and NADPH)
to convert CO2 into useful organic comp
