10.2 Microbial Physio Module 10: Fermentation & Photosynthesis

Which pigment is essential for anoxygenic photosynthesis in Rhodobacter species?

• Chlorophyll a

• Bacteriochlorophyll

• Carotenoids

• Phycocyanin

Answer explanation

Answer: b. Rhodobacter species perform anoxygenic photosynthesis using bacteriochlorophyll

References:

Lee, H. (2009). Two-color Three-pulse Photon Echo Studies on the Photosynthetic Bacterial Reaction Center. University of California, Berkeley. https://escholarship.org/content/qt1d23j386/qt1d23j386.pdf

(Struck & White, 2019).

 

What type of photosynthesis is performed by Cyanobacteria?

• Anoxygenic

• Oxygenic

• Chemotrophic

• None of the above

Answer explanation

Answer: b. Cyanobacteria use oxygenic photosynthesis, producing oxygen as a byproduct

Reference:

Brock et al., 2021

Which electron donor is used in anoxygenic photosynthesis by Chlorobium species?

• Water

• Sulfide

• Oxygen

• Nitrate

Answer explanation

Answer: b. Green sulfur bacteria like Chlorobium use sulfide as an electron donor

Reference:

Brock et al., 2021

Which photosystem is unique to oxygenic photosynthesis?

• PSI

• PSII

• Bacteriochlorophyll

• Phycobilin

Answer explanation

Answer: b. Photosystem II (PSII) is used only in oxygenic photosynthesis by organisms like Cyanobacteria

References:

Brock et al., 2021

Struck & White, 2019

What is the end product of bacterial photosynthesis in Rhodopseudomonas?

• Oxygen

• Sulfur granules

• Carbohydrates

• CO₂

Answer explanation

Answer: c. Rhodopseudomonas produces carbohydrates without releasing oxygen

Reference:

Brock et al., 2021

Which cofactor is essential in bacterial photosynthesis for the transfer of electrons?

• NADH

• FADH2

• NADPH

• ATP

Answer explanation

Answer: c. NADPH is crucial for electron transfer in photosynthesis, enabling the reduction of CO₂ to sugars

Reference:

Struck & White, 2019

What type of photosynthetic bacteria perform cyclic photophosphorylation?

• Rhodobacter sphaeroides

• Anabaena

• Escherichia coli

• Methanococcus jannaschii

Answer explanation

Answer: a. Anoxygenic bacteria like Rhodobacter perform cyclic photophosphorylation to generate ATP without producing oxygen

Reference:

Brock et al., 2021

Seifert, K., Thiel, M., Wicher, E., Wodarczak, M., & Aniecki, M. (2012). Microbiological methods of hydrogen generation. In InTech eBooks. https://doi.org/10.5772/33563

Which pigment is involved in capturing light energy in Cyanobacteria?

• Carotenoids

• Bacteriochlorophyll

• Phycobilins

• Chlorophyll b

Answer explanation

Answer: c. Phycobilins are accessory pigments that aid in capturing light energy in Cyanobacteria

Reference:

Brock et al., 2021

Which photosynthetic bacteria can fix nitrogen under anaerobic conditions?

• Rhodospirillum rubrum

• Escherichia coli

• Lactobacillus acidophilus

• Clostridium difficile

Answer explanation

Answer: a. Rhodospirillum rubrum can fix nitrogen in anaerobic environments during photosynthesis

References:

Struck & White, 2019

What is the primary carbon source for Cyanobacteria during photosynthesis?

• Methane

• Carbon dioxide

• Acetate

• Glucose

Answer explanation

Answer: b. Cyanobacteria use carbon dioxide as the primary carbon source, fixing it into sugars during photosynthesis

Reference:

Brock et al., 2021