5.6-botosynthesis Flashcards
what is a granum?
stacks of thylakoid membranes
what happens at the granum?
the light dependent stage of photosynthesis
what is the stroma?
fluid filled matrix
what happens at the stroma?
light independent stage of photosynthesis
is the outer membrane permeable?
yes, very
what is the chloroplast layer?
the double membrane of the chloroplast
what is the space between the outer and inner membranes called?
intermembrane compartment
what do the intergranal lamellae do?
allow separate grana to be interconnected
what are thylakoids?
flattened membrane bound sacs containing photosynthetic pigments
what happens in thylakoids?
light dependent stage
where is ps1 found?
intergranal lamellae
where is ps2 found?
grana
what are the 5 pigments of chorophyll?
chlorophyll a chlorophyll b carotenoids xanthophyll phaephytin
what is the colour of chlorophyll a?
blue green
what is the colour of chlorophyll b?
yellow green
what is the colour of carotenoids?
orange and yellow
what is the colour of xanthophyll?
yellow brown
what is the colour of phaephytin?
grey
what is the most abundant chlorophyll pigment?
chlorophyll a
how is the structure of the granum adapted to its function?
large surface area
contains pigments + photosystems
contains electron carriers/ ATP synthase
what is a compound made from TP that’s not part of the Calvin cycle?
amino acid
how many carbons does RuBP have?
5
why does the chloroplast contain fat droplets?
membrane formation/phospholipid/cholesterol for membrane
fatty acid/pigment synthesis
where does the light independent stage of photosynthesis take place?
stroma
what photosystems does cyclic phosphorylation involve?
just PSI
what is produced in cyclic photophosphorylation?
a small amount of ATP
how do guard cells work?
their chloroplasts only contain PSI, so they do cycylic photophosphorylation and the ATP produced is used to actively transport potassium so water follow potassium into the cell, causing it to swell and opening the stomata.
what photosystems are involved in non cyclic photophosphorylation?
PSI and PSII
which photophosphorylation does photolysis occur in?
non cyclic
what are the products of non cyclic photophosphorylation?
ATP
reduced NADP
oxygen
where does the light independent stage of photosynthesis take place?
thylakoid membranes
what reaction does RuBisCO catalyse?
CO2 + RuBP —> 2GP
what does GP stand for?
glycerate-3-phosphate
what does TP stand for?
triose phosphate?
what does RuBP stand for?
ribulose biphosphate
what does RuBisCO stand for?
ribulose biphosphate carboxylase-oxygenase
how many carbons does GP have?
3
how many carbons does TP have?
3
how many molecules of TP formed in the calvin cycle leave the calvin cycle?
2/12
what is water stress?
the condition a plant will experience when water supply becomes limited
what are limiting factors?
the factors that affect the rate of a process
what is photosynthesis an example of?
carbon fixation
is photosynthesis endothermic or exothermic?
endo
what is compensation point?
the point when photosynthesis and respiration are happening at the same rate in a plant.
what’s the importance of photosynthetic pigments in photosynthesis?
- accessory pigments pass energy to reaction centres (primary pigments)
- primary pigments/reaction centres becomes oxidised
- for LDR/photophosphorylation
- cause photons to initiate photosythesis
what happens during photolysis?
water gets split into protons, electrons, and oxygen.
why does the calvin cycle only work during daylight?
in daylight the conc of mg2+ increases in stroma, which act as cofactors of rubisco.
what is tp used for?
glucose, starch, cellulose
amino acids, fatty acids, glycerol
what do you have to make sure of when using a photosynthometer?
air tight
no bubbles in capillary tubing
