Photosynthesis Lecture Notes

Flashcards about Photosynthesis

Photosynthesis

The process of converting light energy into chemical energy by green plants.

Chloroplast

Organelle in plant cells where photosynthesis takes place. Contains DNA and prokaryotic ribosomes.

Grana

Location of the light reaction in photosynthesis.

Stroma

Location of the carbon fixation reaction in photosynthesis.

Quantasome

A complex of pigment and protein that performs light reactions; it is regularly arranged into thylakoid membranes.

Chlorophyll

Pigment involved in photosynthesis; similar in structure to hemoglobin, containing a porphyrin ring and Mg.

Chlorophyll a

Chlorophyll that functions as the reaction center pigment in photosynthesis.

Carotenoids

Accessory pigments that absorb light at different wavelengths and transfer energy to chlorophyll a, protecting it from intense light.

Absorption Spectrum

Graph showing the absorption of light by photosynthetic pigments.

Action Spectrum

Graph showing the rate of photosynthesis at various wavelengths of light.

Compensation Point

Point at which the rate of photosynthesis equals the rate of respiration.

Light Saturation Point

Point at which the rate of photosynthesis no longer increases with increasing light intensity.

CO2 and Photosynthesis

Photosynthesis will increase until this substrate becomes limited.

Light Reaction

Stage of photosynthesis where water is split and oxygen is released, occurring in the thylakoid membrane and producing ATP and NADPH.

Carbon Fixation Reaction

Stage of photosynthesis where carbon dioxide is fixed and converted into glucose, occurring in the stroma.

Ruben's Experiment

Experiment demonstrating that oxygen produced during photosynthesis comes from water.

Hill's Experiment

Experiment demonstrating oxygen production in the absence of CO2 absorption.

Calvin Cycle

Cycle also know as the Calvin-Benson cycle, where carbon dioxide is fixed to produce glucose.

Light Reaction

Light-dependent reactions occurs in the Chloroplast Grana in the Thylakoid membrane

Antenna Complex

A cluster of pigment molecules in the thylakoid membrane that capture light energy.

Reaction center

Where a dimer Chlorophyll a is located.

Photosystems

Photosystem I (PSI) and Photosystem II (PSII)

photosystemⅠ

Photosystem with Chlorophylla-P700 reaction center.

photosystemⅡ

Photosystem with Chlorophyl l a-P680 reaction center.

Photophosphorylation

Noncyclic and cyclic photophosphorylation reactions.

Chemical Osmotic Phosphorylation

Process by which ATP is generated across the thylakoid membrane via a proton gradient.

Rubisco

Enzyme responsible for catalyzing the first major step of carbon fixation.