Weekly Quiz 6: Electron Transport and Photosynthesis Concepts

Electron transport system

A series of complexes that transfer electrons from electron donors to electron acceptors via redox reactions.

NADH

A common electron donor that can donate electrons to an electron transport system.

H2

A molecule that can donate electrons to an electron transport system.

CO2

A molecule that cannot donate electrons to an electron transport system.

Fe2+

A molecule that can donate electrons to an electron transport system.

NH4+

A molecule that can donate electrons to an electron transport system.

Oxidative phosphorylation

The production of ATP via the operation of an electron transport system.

Oxygenic photosynthesis

A form of photosynthesis performed by cyanobacteria and green plants that uses H2O as the electron source.

Initial substrate oxidoreductase

A component of an electron transport system.

Mobile electron carrier

A component of an electron transport system that transfers electrons between complexes.

Light-driven proton pump

A component that is NOT part of an electron transport system.

Terminal oxidase

A component of an electron transport system that transfers electrons to the final electron acceptor.

Lithotrophy

A metabolic process where microbes use inorganic compounds as electron sources.

Quinones

Molecules that play the role of the mobile electron carrier in an electron transport system.

Anaerobic photosystem I

Takes electrons from H2O; electrons used to pump H+ and make NADPH; used by cyanobacteria and plants.

Anaerobic photosystem II

Takes electrons from chlorophyll itself; too weak to make NADPH; pumps a few H+ to make ATP and returns the electrons to chlorophyll.

Oxygenic Z pathway

Takes electrons from H2 or H2S; uses the electrons to make NADPH; doesn't pump H+ but does make an H+ gradient by releasing protons outside the membrane.

Redox tower

A representation used to determine the energy yield from different electron donor and acceptor pairs.

Strongest electron acceptor

Among the listed options, the strongest electron acceptor can be determined using the redox tower.

F1FO ATPase

The molecular machine that converts energy in the form of the proton motive force into ATP.

Proton motive force

The force generated by the movement of protons across a membrane, used to power various cellular activities.

Carbon fixation

The process that takes place in photosynthetic cyanobacteria, primarily in the carboxysome.

Energy from light

Captured by the antenna complex during photosynthesis.

Bacterial activities powered by proton motive force

Includes rotation of the flagellum, allowing swimming.