Photosynthesis

Question 1

what is the abosrption spectrum of chlorophyll a and b

Answer 1

400-500nm and 600-700nm

Question 2

what structure in chlorophyll makes it good at absorbing light energy

Answer 2

the conjugated double bond system

Question 3

what atom exists in chlorophyll

Answer 3

magnesium

Question 4

what is the structural difference between chlorophyll and pheophytin

Answer 4

two hydrogen atoms replace the magnesium atom

Question 5

why is the structure of pheophytin much more stable than chlorophylls

Answer 5

because of the hydrogen bond interactions

Question 6

what is the P value of the special pair chlorophyll molecules

Answer 6

P960

Question 7

what polypeptides form the photosynthetic reaction centre in Rhodoseudomonas?

Answer 7

4 polypeptides - L, M, H and cytochrome subunit.

Question 8

what structures are similar to L and M?

Answer 8

The D2 and D1 structures of the PSII complex

Question 9

what is an important complex of the PSII complex

Answer 9

the oxygen evolving complex

Question 10

What is the P value for the special pair in PSII

Answer 10

P680

Question 11

What does PSII reduce

Answer 11

plastoquinone

Question 12

what oxidises the reduced plastoquinone

Answer 12

cytochrome b6f complex

Question 13

what structure in the mitochondira is b6f complex homologous to?

Answer 13

bc1

Question 14

what protein links the bc1 complez and cytochrome oxidase

Answer 14

plastocyanin

Question 15

what is the special pairs P value in PS1

Answer 15

p700

Question 16

what clusters does the PS1 complex consist of

Answer 16

3 4Fe-4S complexes

Question 17

what does p700 eventually reduce?

Answer 17

Ferradoxin

Question 18

what does ferrdoxin donate electrons to and what does this eventually cause?

Answer 18

Ferredoxin-NADP+ reductase which converts NADP+ to NADPH

Question 19

what reduced photosystem I

Answer 19

plastocyanin

Question 20

how is light energy transferred from one chlorophyll to another

Answer 20

by resonance energy transfer