Exam 9, 6, 51 Flashcards
what is the relationship between visible light and the electromagnetic spectrum (EM)?
visible light is a small portion of the EM spectrum
how does radiation travel along the EM spectrum?
as waves
what is a wavelength?
the distance from one peak to the next
what are photons?
small particles which make up light
what is the difference in energy per photon for shorter wavelengths versus longer wavelengths?
shorter wavelength of light have more energy per photon
when a molecules absorbs a photon of light, what happens to an electrons?
electrons become energized
when a molecules absorbs a photon and electrons become energized, what happens?
-atoms may return to ground state and release energy as heat of fluoresces
-the electron may leave the atom and be accepted by an electron acceptor molecule (redox)
what encloses chloroplast?
an outer and inner membrane
what does stroma contain?
enzymes required to produce carbohydrates
the inner layer of the chloroplasts encloses what?
fluid filled stroma
what is suspended within the stroma?
a third system of membranes called the thylakoids
how are thylakoid sacs arranged?
in stacks called grana (granum for singlular)
what is the inside of a thylakoid called?
the thylakoid lumen
what is found inside the thylakoid membrane?
pigments called chlorophyll
what do pigments absorb differently?
different pigments absorb light of different wavelengths
what is chlorophyll?
the main pigment of photosynthesis, which absorbs red and blue light but reflects green light
what is the function of chlorophyll a?
to initiate light dependent reactions of photosynthesis (forms the reaction center)
what is chlorophyll b?
an accessory pigment
what are carotenoids?
yellow and orange accessory photosynthetic pigments which absorb different wavelengths form chlorophyll
equation for photosynthesis?
6CO2 + 6H2O –> C6H12O6 + 6O2
what are the two phases that divide photosynthesis?
light dependent reactions and carbon fixation reactions
what is the function of light dependent reactions?
to convert light energy to chemical energy
where do light dependent reactions occur?
the thylakoid
when do light dependent reactions begin?
as soon as chlorophyll captures light energy