Chap. 10 (Vocab) Flashcards
Photosynthesis
Conversion of light energy to chemical energy stored in sugars
Autotrophs
Produce their own food using sunlight or chemical energy
Heterotrophs
Consume other organisms to obtain their food, meaning they cannot make their own food
Chroloplast
Perform photosynthesis
Mesophyll
Internal tissue of a plant leaf
Stomata
Tiny pores on the surface of plant leaves
Stroma
Fluid outside thylakoid containing ribosomes + DNA
Thylakoid
Flat, membranous sac inside a chloroplast. Convert light energy into chemical energy
Granum
Stack that makes up thylakoids
Chlorophyll
Green pigment in thylakoid
Light Reactions
Sunlight energy captured by chlorophyll convert it into chemical energy stored as ATP and NADPH
Calvin Cycle
Second stage where carbon dioxide is converted into sugar molecules (glucose) using energy from ATP and NADPH within the stroma of the chloroplast
NADPH
Reduced form of NADP that stores electrons produced during light reactions
Photophosphorylation
Generation of ATP from ADP + phosphate by chemiosmosis
Carbon Fixation
Convert inorganic carbon dioxide from the atmosphere into organic compounds (sugar)
Wavelength
Distance between crests of waves
Crest
Highest point of a wave
Visible Light
Portion of spectrum that can be detected by the human eye
Electromagnetic Spectrum
Spectrum of electromagnetic radiation
Photons
Single particle of light energy absorbed by chlorophyll molecules
Pigments
Substances that absorb light
Spectophotometer
Measure of light absorbed at specific wavelengths
Absorption Spectrum
Describes the wavelengths absorbed, shows which colors of light are most effectively captured
Chlorophyll a
Absorbs blue-violet light + reflects green
Chlorophyll b
Absorbs red light + reflects green
-Collects energy and passes to a
Action Spectrum
How effective different wavelengths are at producing a biological response
Carotenoids
Pigments responsible for yellow, orange, and red colors
Photosystem
Protein in thylakoid that absorbs light energy and transfers it to electrons
Reaction-center Complex
Protein that acts as the primary site for converting light energy into chemical energy by initiating process of electron transfer
Light Harvesting Complex
Proteins that absorb light energy from the sun and transfer it to the reaction center of a photosystem
Primary Electron Acceptor
Molecule that accepts electrons and is reduced
Photosystem I
Protein in thylakoid membrane that uses the electrons from PS II to make NADPH
Photosystem II
Protein in thylakoid membrane that splits water molecules to release oxygen and provides electrons to PS I
Linear Electron Flow
Electrons are passed from one molecule to another in a linear pathway, converting light energy into chemical energy stored in ATP and NADPH
Cyclic Electron Flow
Electrons are recycled around PS I making ATP
- only uses PS I
Glyceraldehyde 3-phosphate (G3P)
- 3-carbon carbohydrate
- Direct product from Calvin Cycle
Rubisco
Enzyme that catalyzes attachment of CO2 to a 5-carbon sugar
Potorespiration
Enzyme RuBisCO uses ATP and accidentally binds to oxygen instead of carbon dioxide during photosynthesis, leading to the release of carbon dioxide and a loss of fixed carbon
Bundle Seath Cells
Cells that form tightly packed layer around veins in leaf
PEP Carboxylase
Enzyme crucial for carbon fixation in C4
CAM
Photosynthesis where plants open their stomata at night to collect carbon dioxide and store it as an acid and use it during the day for photosynthesis when their stomata are closed to minimize water loss
