photosynthesis

Question 1

describe the Light Dependent Reaction

Answer 1

-photoionisation: chlorophyll absorbs light energy via photoionisation and excites electrons so they move from the chlorophyll into electron transfer chain releasing energy

-photophosphorylation: this released energy is used to form a proton gradient (of H+ ions) these H+ ions diffuse through ATP synthase providing energy to join ADP and Pi to form ATP
.
-photolysis: water molecules splits into H+ ions , e- and O2.
NADP is reduced by electrons and
H+.

Question 2

describe light independent reaction

Answer 2

-carbon fixation: carbon binds to RuBP through the enzyme rubisco.
and produces two GP molecules,

-reduction: GP is reduced into TP using reduced NADP and energy from ATP
-some TP is converted into glucose/starch/cellulose

regeneration: the remaining TP is used to regenerate RuBP -using phosphate from ATP

Question 3

what are some factors that affect photosynthesis in order

Answer 3

-light intensity
-concentration of carbon dioxide
-temperature
-amount of RuBP or rubisco

Question 4

where does LDR and LIR take place

Answer 4

LDR - thylakoid
LIR - stroma

Question 5

what is the thylakoid

Answer 5

single, flattened, membrane bound sacs found in the chloroplast

Question 6

what is a granum/grana

Answer 6

stacks of thylakoid

Question 7

what is the stroma

Answer 7

its a protein rich matrix(fluid) surrounding the thylakoids, containing enzymes, starch grains and ribosomes

Question 8

what is photophosphorylation

Answer 8

ATP production in LDR

Question 9

what is photolysis

Answer 9

the splitting of a water molecule to produce H+ ions and e- and O2

Question 10

what is the calvin cycle

Answer 10

cyclical chain of reactions in LIR

Question 11

what happen if there was less light

Answer 11

-less production of ATP and reduced NADP
-which means less GP being reduced into TP
-so less organic compounds synthesised.
-also less TP regenerated into RuBP
-which means less RuBP binding CO2