photosynthesis

Question 1

stroma

Answer 1

stroma is space in chloroplasts

Question 2

stack of thylakoids

Answer 2

granum

Question 3

thylakoids adaptation

Answer 3

membranes have large surface area
thylakoid space is needed for accumulation of protons
stroma contains enzymes needed or calvin cycle (rubiso)

Question 4

light dependent reaction

Answer 4

first stage of photosynthesis inc PS1 and PS2

Question 5

photolysis

Answer 5

light dependent
H2O-> 2H+ +2E- + .5O2
electrons enter photosystem 2
hydrogen reduces NAD+
oxygen is by product

Question 6

photsystem

Answer 6

a group of pigments located in thylakoid membrane (e.g. chlorophyll a )

Question 7

photosystem 2

Answer 7

electrons become excited due to light energy
absorption of light causes photoionisation of chlorophyll and electrons enter the etc and passed down losing energy as they move
chemiosmosis occurs (energy used to to pump H+ from stroma to thylakoid lumen) and H+ conc grad made (photophosphorylation)
H+ pass back by atp synthase which makes ATP from ADP and inorganic phosphate (ADP+Pi->ATP)
electrons move to ps 1

Question 8

photosystem 1

Answer 8

electrons become excited due to light energy
absorption of light causes photoionisation of chlorophyll and electrons enter the etc
energy used to pump H+ into thylakoid lumen

NAD+ + electrons release + H+ grad H+ -> NADH (reduction)

Question 9

light independent stage

Answer 9

happens in stroma (calvin cycle)
however uses ATP and NADH from dependent

Question 10

kalvin cycle

Answer 10

1) CO2 is fixed to ribulose bisphosphate (RuBP) by RUBISCO
2) 6C molecule immediately splits to 2 x glycerate-3-phosphate
3P reduced to GALP (suning ATP and NADPH)
GALP makes hexose sugars (inc glucose)
rest of GALP regenerate RUBP for cycle to repeat

Question 11

role of light dependent products in light inependent reaction

Answer 11

NADPH provided H to reduce GP to GALP
ATP provided energy to reduce GP to GALP

Question 12

non-cyclic photophosphorylation

Answer 12

electrons become excited and reaction gains energy at start of PS11 and PS1 when light hits and then energy is lost as electrons move down the ETC

Question 13

cyclic photophosphorylation

Answer 13

during excess light (temporary)
lack of NADP+ means NAH cannot be made bc it is the limiting factor so electrons from ps1 and re-excited fed back into ps2 to create more ATP