Chapter 8 - Photosynthesis Flashcards
(48 cards)
Photosynthesis
Process used by plants and other organisms to convert light energy, normally from the Sun, into chemical energy that can be later released to fuel the organisms’ activities.
Carbon fixation
The conversion process of inorganic carbon (carbon dioxide) to organic compounds by living organisms.
Thylakoid
A membrane-bound compartment inside chloroplasts and cyanobacteria. The site of the light-dependent reactions of photosynthesis. Consist of a thylakoid membrane surrounding a thylakoid lumen.
Grana
One of the structural units of a chloroplast in vascular plants, consisting of layers of thylakoids.
Chlorophyll
Green pigments found in cyanobacteria and the chloroplasts of algae and plants. Allows plants to absorb energy from light.
Stroma Lamallae
The holow tube-like channel that is paired with a stack of thylakoids (Granum). Transports nutients and substance needed for the thylakoids in order to keep the organelle alive and functioning.
Stroma
The colorless fluid surrounding the grana within the chloroplast.
Photosystem
Functional and structural units of protein complexes involved in photosynthesis that together carry out the primary photochemistry of photosynthesis: the absorption of light and the transfer of energy and electrons.
Light-dependent reaction
Take place on the thylakoid membranes. Photosystems absorb light and turn them into energy.
Light-independent reaction
Chemical reactions that convert carbon dioxide and other compounds into glucose. Occur in the stroma, the fluid-filled area of a chloroplast outside of the thylakoid membranes.
Chlorophyll a
A type of chlorophyll that is most common and predominant in all oxygen-evolving photosynthetic organisms.
photoelectric effect
Light striking the chlorophyll molecule causing it to be energetically exited.
chlorophyll b
Accessory photosynthetic pigment
accessory pigment
Light-absorbing compounds, found in photosynthetic organisms, that work in conjunction with chlorophyll a.
action spectrum
The efficiency with which electromagnetic radiation produces a photo-chemical reaction plotted as a function of the wavelength of the radiation.The action Spectrum is an indicator of which wavelength of light can be used by a plant to allow photosynthesis.
carotenoid
Any of a group of accessory pigments found in plants; in addition to absorbing light energy, these pigments act as antioxidants, scavenging potentially damaging free radicals.
phycobilin
Light-capturing pigments found in cyanobacteria and in the chloroplasts of red algae.
antenna complex
A complex of of hundreds of pigment molecules in a photosystem that collects photons and feeds the light energy to a reaction center
reaction center
A transmembrane protein complex in a photosystem that receives energy from the antenna complex exciting an electron that is passed to an acceptor molecule
photosystem I
After b6-f complex. Located in thylakoid membrane. Absorbs photons, exciting electrons that are passed through a carrier to reduce NADP+ to NADPH. Electrons are replaced by electron transport from photosystem II. P700. Absorbs longer wls (>680).
photosystem II
The first protein complex. Located in the thylakoid membrane. Absorbs photons, exciting the electrons that are passed to PQ. Electons lost are replaced by oxidation of H20. Absorbs shorther wls (<680). Involved in creation of ATP and hydrolysis of H20.
P700 (pigment 700)
The reaction center chlorophyll (or the primary electron donor) of photosystem I that is most reactive and best in absorbing light at wavelength of 700 nm.
P680 (pigment 680)
Photosystem II primary donor. refers to any of the 2 special chlorophyll dimers (also named special pairs), PD1 or PD2. Absorption maximum in the red part of the visible spectrum (680 nm).
b6-f complex
Receives electrons from PQ and passes them PC. Provides energy for b6-f to pump protons into Thykaloid.