Photosynthesis Flashcards

Vocabulary flashcards based on lecture notes about photosynthesis.

Visible Spectrum

The portion of the electromagnetic spectrum that we can see, consisting of the colors red, orange, yellow, green, indigo, and violet.

Photons

Discrete particles that light behaves as though it is made up of, each with a fixed quantity of energy.

Pigments

Substances that absorb light.

Chlorophyll

A pigment that absorbs violet-blue and red light while transmitting and reflecting green light.

Absorption Spectrum

A graph plotting a pigment's light absorption as a function of wavelength.

Action Spectrum

A graph of the effectiveness of different wavelengths of light in driving photosynthesis.

Photosystems

Groups of pigment molecules in the thylakoid membrane of chloroplasts, consisting of a light-harvesting complex and a reaction center.

Light-harvesting complex

Made up of chlorophyll and carotenoid molecules, gathers light effectively.

Stroma

Fluid-filled area enclosed by the two membranes of the chloroplast.

Thylakoids

Interconnected membranous sacs within the stroma.

Thylakoid space

Compartment segregated by thylakoids from the stroma.

Stomata

Tiny pores on the exterior of the lower epidermis of a leaf through which carbon dioxide enters and oxygen and water exit the leaf.

Transpiration

The loss of water through open stomata.

Light Reactions

The stage of photosynthesis that occurs in the thylakoid membranes where light energy is converted to the chemical energy of ATP and NADPH; water is split and O2 is released.

Photophosphorylation

The process of generating ATP using chemiosmosis to power the addition of a phosphate group to ADP.

Calvin Cycle

The stage of photosynthesis that occurs in the stroma, where CO2 is incorporated into organic molecules in carbon fixation, and sugars are formed using fixed carbon plus NADPH and ATP from the light reactions.

Rubisco

The enzyme that catalyzes the first step of the Calvin cycle, where CO2 molecules are attached to RuBP.

C4 Photosynthesis

A metabolic adaptation to reduce photorespiration.

CAM

A metabolic adaptation to reduce photorespiration in hot, arid climates.