Photosynthesis

Question 1

Chlorophyll a

Answer 1

A primary pigment light energy excites electrons from magnesium
Exists as PSII 680 PSI 700

Question 2

Photosynthetic pigments

Answer 2

Accessory pigments absorb wide range of light pass energy on

Question 3

Thylakoids

Answer 3

Discs that contain photosynthetic pigments - v large SA

Question 4

Light dependent stage

Answer 4

Photolysis splits water into hydrogen ions and electrons
Light hits pII and excites pair of e-
E- passed along cytochromes this releases energy which pumps h+ ions in
Light hits PI and exited 2e-
These join with NADP to for NADPred
H+ ions pump through ATP synthase
Forms atp

Question 5

ATP synthase

Answer 5

EMF which converts kinetic energy into chemical energy

Question 6

Light independent stage

Answer 6

Takes place in the stroma
6 full turns produce glucose

Question 7

RuBP to 2 GP

Answer 7

RubisCo + CO2 carboxylation
GP forms amino acids and fatty acids

Question 8

2GP to 2TP

Answer 8

2 NADPred -> 2 NADP
Uses 2 ATP
TP forms glycerol and hexose sugars
Reduction

Question 9

2TP to RuBP

Answer 9

Regeneration
Uses ATP

Question 10

Light intensity effects on Calvin cycle (low light)

Answer 10

Less light energy
Less ATP and NADPred formed
GP cannot convert to TP
TP cannot convert to RuBP
RuBP convert to GP CO2 levels = same

Question 11

Limiatations of using photosynthometer

Answer 11

Take into account effect of respiration
Some O2 may dissolve into the water
Lamp= heat
Dark only 1 light source
Not acclimatised

Question 12

Cyclic light dependent stage

Answer 12

Occurs at same time
Only produces ATP and uses only PSI
No O2 or NADPred