Quiz 9.1-9.6 Flashcards
what is photosynthesis?
the first step in energy flow through most of the living world
what is visible light?
a small portion of the electromagnetic spectrum
how does radiation in the EM spectrum travel?
as waves
what is a wavelength?
the distance from one wave peak to the next
what are photons?
small particles of energy that make up light
what is the relationship between shorter wavelengths and longer wavelengths?
shorter wavelengths have more energy per photon
what happens to one electrons when a molecule absorbs a photon of light?
it become energized
after a molecule absorbs a photon of light and the electron is energized what happens?
the atom may return to ground state and energy is given off as heat or fluoresces or the energy of the electron leaves the atom and is accepted by an electron acceptor
what is the chloroplasts enclosed by?
an outer and inner membrane
what does the inner membrane enclose?
fluid filled stroma that contain enzymes required to produce carbohydrates
what is the third system of membrane suspended in the stroma?
thylakoids
what is the inside of a thylakoid called?
thylakoid lumen
what is a stack of thylakoids called?
grana
what do thylakoid membranes include?
pigments
What is the main pigment of photosynthesis?
chlorophyll
what lights does chlorophyll absorbs and reflect?
absorbs red and blue and reflects green
what is chlorophyll a?
a blue-green the initiates light dependent reactions (forming the reaction center)
what is chlorophyll b?
yellow-green, an accessory pigment
what are carotenoids?
yellow and orange accessory photosynthetic pigments (absorbs different wavelengths from chlorophyll)
what is the absorption spectra?
measures the efficiency of light absorptions (chlorophyll a and b)
what is the action spectra?
measures the efficiency of photosynthesis
what are the two phases of photosynthesis?
light dependent reactions and carbon fixation reactions
what does the light dependent reaction do?
converts light energy to chemical energ, starts as soon as chlorophyll captures light
where does the light dependent reaction occur?
the thylakoids
what happens during the light dependent reaction?
an energized electron is transferred to an acceptor molecules and replaced by an electron from H2O, H2O is split into O2
what are the products of the light dependent reaction?
Atp, NADH, and O2
what is the carbon fixation reaction?
a reaction that fixes carbon ants from CO2 to existing skeletons of organic molecules
what does the carbon fixation reaction do?
transfers energy from ATP and NADPH molecules from the light dependent reaction to chemical bonds in carbohydrates
where does the carbon fixation reaction occur?
the storm of the chloroplast
how many molecules make an antenna complex?
250-400
what are clusters of antenna complexes called?
photosystems
what is photo system 1’s absorption peak?
P 700
what is photo system 2’s absorption peak?
P 680
what does a pigment molecule in an antenna complex do?
absorbs a photon of light energy
what is a primary electron acceptor in photosystem 2?
pheophytin
how many electrons does the reaction center or photosystem 2 lose?
2
what is photolysis?
the splitting of water
what are the products of photosystem 2?
2 electrons, 2 H+, and 1 oxygen
