Photosynthesis Vocabulary

Flashcards for Photosynthesis Lecture Review

Photosynthesis

Energy within light is captured and used to synthesize sugars and produce oxygen.

Autotrophs

Produce organic molecules from inorganic molecules.

Chloroplast

Organelle in plants and algae that carries out photosynthesis.

Granum

Stack of thylakoids.

Light reactions

Use light energy converts light energy to chemical energy.

Calvin Cycle

Uses ATP and NADPH to incorporate CO2 into carbohydrate.

Photons

Massless particles traveling in a wavelike pattern.

Pigments

A substance that can absorb visible light.

Absorption spectrum

Wavelengths that are absorbed by different pigments.

Action spectrum

Rate of photosynthesis by whole plant at specific wavelengths.

Reaction-center complex

Complex of proteins in the reaction center.

Light-harvesting complexes

Pigment molecules bound to proteins transfer the energy of photons to the reaction center.

Photosystem II (PS II)

Excited e- are removed from water to replenish e- removed from P680. Oxidation of H2O yields O2. Adds H+ to the lumen.

Photosystem I (PS I)

Best at absorbing a wavelength of 700 nm.

Photophosphorylation

ATP synthesis in chloroplasts.

Linear Electron Flow

Electrons begin at PSII and eventually transfer to NADP+ àNADPH.

Cyclic photophosphorylation

Path of e- is cyclic.

Homologous genes

Similar because they are derived from a common ancestral gene.

Calvin Cycle

Uses ATP and NADPH to fix CO2 into sugar.

Carbon fixation

CO2 is incorporated into RuBP (5C sugar).

Reduction and Carb production

ATP converts 3PG to 1,3-BPG. 1,3-BPG is then reduced to G3P.

Regeneration of RuBP

10 remaining G3P are used to regenerate RuBP.

Alternative Mechanisms of Carbon Fixation

On hot, dry days, plants close stomata, which reduces evaporative water loss, but also prevents gas exchange.

Photorespiration

Rubisco fixes O2 instead of CO2 and produces a two-carbon compound.