Lecture #11 – Cellular Energetics, Part 3

These flashcards cover key concepts, definitions, and processes related to cellular energetics and photosynthesis as discussed in lecture.

Chloroplasts

Organelles found in plant cells where photosynthesis occurs.

Photosynthesis

The process by which plants convert light energy into chemical energy stored in carbohydrates.

Light-dependent reactions

Reactions in photosynthesis that convert solar energy into chemical energy in the form of ATP and NADPH.

Light-independent reactions (Calvin Cycle)

Reactions that do not require light, where ATP and NADPH are used to convert CO2 into glucose.

C3 plants

Plants that use the Calvin cycle for carbon fixation, producing a three-carbon compound.

C4 plants

Plants that fix CO2 into four-carbon compounds to reduce water loss and improve photosynthetic efficiency.

CAM plants

Plants that fix CO2 at night to reduce water loss, utilizing crassulacean acid metabolism.

NADPH

Nicotinamide adenine dinucleotide phosphate; an electron carrier used in photosynthesis.

ATP

Adenosine triphosphate; the energy currency of the cell, used in various biological processes.

Rubisco

Ribulose bisphosphate carboxylase/oxygenase; the enzyme that catalyzes the carboxylation of RuBP in the Calvin cycle.

Photon

A particle of light energy.

Thylakoid membrane

Membrane-bound compartments inside chloroplasts where the light-dependent reactions take place.

Electron transport chain

A series of protein complexes that transfer electrons and create a proton gradient, leading to ATP synthesis.

Photorespiration

A process where O2 is consumed and CO2 is released, reducing the efficiency of photosynthesis.

Proton motive force

The potential energy stored as a gradient of protons across a membrane, used to drive ATP synthesis.

Oxidation-reduction (redox) reaction

A chemical reaction involving the transfer of electrons from one molecule to another, crucial for energy transformations in photosynthesis.

Cyclic photophosphorylation

A process that produces ATP without generating NADPH, occurring in photosystem I.

Non-cyclic photophosphorylation

A process that generates both ATP and NADPH, involving both photosystems II and I.

Z scheme

A model that describes the transfer of electrons from water to NADP+ during the light reactions of photosynthesis.

Glyceraldehyde 3-phosphate (G3P)

The three-carbon sugar produced in the Calvin cycle that is the precursor to glucose and other carbohydrates.