7. Photosynthetic Bacteria

Question 1

Lack of which photosystem = no O2 production? Why?

Answer 1

Lack of PSII

No hydrolysis of water = no O2 production

Question 2

2 major groups of photosynthetic bacteria?

Answer 2

Cyanobacteria

Green & purple photosynthetic bacteria

Question 3

What do they call cyanobacteria on TV?

Answer 3

blue-green algae

Question 4

Which photosystem(s) do cyanobacteria have?

Answer 4

PSI and II

Question 5

Photopigments of cyanobacteria?

Answer 5

Chlorophyll and accessory pigments

Question 6

Cyanobacteria e- donor? Is there O2 production?

Answer 6

E- donor = H2O

O2 production - yes (oxygenic)

Question 7

What are phycobilisomes, what do they contain, and what’s their function?

Answer 7

Particles on membranes of cyanobacteria that contain photosynthetic pigments and ETC’s

Contain phycobilin pigments (phycocyanin and phycoerythrin)

Transfer energy to PSII

Question 8

Products of cyanobacteria light reaction

Answer 8

ATP, NADPH, O2

Question 9

Common habitats of cyanobacteria

Answer 9

Aerobic enviros, all aquatic enviros worldwide

Question 10

Morphology of cyanobacteria?

Answer 10

Cocci, filamentous, spiral

Question 11

Cyanobacteria motility?

Answer 11

“Gliding motility” => secrete slime layer, move along it

Question 12

Cyanobacteria metabolism (“troph”)?

Answer 12

Most photolithoautotrophs

some chemoorganoheterotrophs (in the dark)

Question 13

Increase of nutrients from urban ruin-off cause ______

Answer 13

blooms

Question 14

Cyanobacteria are natural ________ with ______ (_______)

Answer 14

symbionts with fungi (lichen)

Question 15

3 methods of cyanobacteria reproduction? All are by _________ reproduction

Answer 15

Budding, fission, fragmentation

Asexual reproduction

Question 16

Cyanobacteria can also ____________

They convert ________ to a usable __________

Answer 16

Fix nitrogen

Convert N2 to a usable nitrogen source( NH4+)

Question 17

When do cyanobacteria fix N2?

Answer 17

In the dark when usable N sources are depleted

Question 18

Nitrogen sources for cyanobacteria?

Answer 18

NO3-, NH4+, amino acids

Question 19

Nitrogenase is inhibited by ____

Answer 19

O2

Question 20

What catalyzes nitrogen fixation in cyanobacteria?

Answer 20

Nitrogenase

Question 21

Have to break _______ bond between the 2 nitrogen atoms of N2

Answer 21

triple

Question 22

Green and purple photosynthetic bacteria have which photosystem(s)?

Answer 22

PSI only => cyclic phosphorylation

Question 23

Photopigment in G&P photosynthetic bact?

Answer 23

Bacteriochlorophyll

Question 24

G&P photosynthetic bact electron donors (sources)?

Answer 24

H2, H2S, S0

Question 25

G&P photosynthetic bacteria products of light reactions?

Answer 25

ATP (cyclic phosphorylation)

Question 26

G&P photosynthetic bacteria O2 production?

Answer 26

No => anoxygenic

No PSII => no hydrolysis of water => no O2

Question 27

G&P photosynthetic bacteria habitats?

Answer 27

Lower levels in water column

Most often in anaerobic sediments

Question 28

How do G&P photosynthetic bacteria regulate buoyancy/height in water?

Answer 28

Use gas vacuoles

Question 29

G&P photosynthetic bacteria that don’t have gas vacuoles fluorish in _______-rich mud

Answer 29

sulfide

Question 30

Main difference between non-cyclic and cyclic photophosphorylation?

Answer 30

Noncyclic = PSI and II involved

Cyclic = Only PSI (makes ATP, but less efficiently)

Question 31

End products of noncyclic photophosphorylation?

Answer 31

O2, ATP, NADPH, H+

Question 32

ATP synthase is driven by H+ gradient generated earlier around ___________

Answer 32

photosystem II

Question 33

Enzyme that converts NADP+ to NADPH during photosynthesis?

Answer 33

Pyridine nucelotide reductase

Question 34

Electron movement in photosynthesis

PSII –> ______ –> cytochrome bf –> ________ –> PSI –> _____ –> _____

Answer 34

plastoquinone, plastocyanin, ferredoxin, pyridine nucleotide reductase

Question 35

About ____% of all photosynthesis is carried out by photosynthetic bacteria and algar

Answer 35

50%