5.2 Flashcards
what is an autotroph
organisms that make organic compounds from simple inorganic compounds in their environment
define photosynthesis
the process by which living organisms capture light energy using chlorophyll to convert CO2 + O2 into simple sugars
what is a heterotroph
organisms that obtain complex organic molecules by feeding on other living/dead organisms
what is the balanced symbol equation for photosynthesis
6CO2 + 6H2O -> C6H12O6 + 6O2
explain the structure of a chloroplast
circular DNA
lamellae
thylakoid
granum
stroma
lipid droplets
starch granule
ribosomes
where is chlorophyll found in a chloroplast
thylakoid
what is the role of the lamellae
acts as a skeleton
maintains a working distance between grana to maximize light for efficiency
what is the role of the stroma
contains the enzymes needed for photosynthesis
what are the main photosynthetic pigments
chlorophyll a (blue-green)
chlorophyll b (yellow-green)
carotenoids (orange-yellow )
what is the absorption spectrum
a graph of the amount of light absorbed by a pigment against the wavelength of light
what is the action spectrum
a graph demonstrating the rate of photosynthesis against the wavelength of light
how should you extract the pigment from a leaf for chromatography
grind leaves with propanone then filter till the filtrate is green
how do you calculate the Rf vale
distance of solute/distance of solvent
where are photosystem particles 1 & 2 found
PS1 - integral lamellae
PS2 - grana
where does the light dependent reaction occur
thylakoid membrane
what is produced in the light dependent reaction
ATP
H+ ions for the production of carbohydrates
what reactions make up the light dependent reactions
cyclic & non-cyclic photophosphorylation
Summarize what happens in cyclic photophosphorylation
light hits photosystem 1
electrons are exited & leave
electrons taken up by electron acceptor and transported to the electron transport chain where energy is released for chemiosmosis
they then rejoin photosystem 1
what occurs in chemiosmosis
H+ ions actively pumped from low concentration in stroma to high concentration in the thylakoid space
creates a concentration gradient
H+ ions diffuse back across thylakoid membrane via ATP synthase which catalyzes production of ATP
summarize what happens in the light dependent reaction
light hits chlorophyll electrons become exited so leave the chlorophyll molecule
exited electrons are then picked up by electron acceptors which synthesizes ATP via cyclic & non cyclic photophosphorylation
summarize noncyclic photophosphorylation
lights hits photosystem 2
2 electrons gain energy
both leave photosystem 2 & travel to the electron transport chain & are replaced by electrons from the photolysis of water energy released from the electron transport chain helps in chemiosmosis electrons from photosystem 2 pass to photosystem 1 combined with H+ ions from photolysis of water and NADP is reduced
what is a photochemical reaction
a reaction initiated by light
define photolysis
the splitting of a molecule using light
where does the light independent reaction happen
the stroma
what reaction makes up the light independent reaction
Calvin Benson cycle
what is produced in the light independent reaction
synthesis of carbohydrates
describe the Calvin Benson cycle
CO2 + RuBp (5C) catalysed by Rubisco to form a 6 carbon unstable intermediate
it then forms 2GP (3C)
2GALP formed through the oxidation of NADPH and conversion of ATP to ADP
1/6 carbons from the 2GALP go on to form hexose sugars and 5/6 of the carbons form RuBp for the cycle to repeat
what initiates the Calvin Benson cycle
carbon fixation by RuBp catalyzed by Rubisco
how can GALP be used around a plant
production of glucose fuel to provide energy
building blocks of amino acids
converted to acetyl coenzyme
production of nucleic acid
what is gluconeogenesis
the synthesis of glucose from non-carbohydrates
what are the 3 main limiting factors of photosynthesis
light intensity
CO2 concentration
temperature
