Chapter 7: Photosynthesis Flashcards
photosynthesis converts solar energy into
chemical energy
photosynthesis directly and indirectly
sustains the entire living world
autotrophs produce
organic molecules from CO2 and other inorganic molecules
photoautotrophs use
energy of sunlight to make organic molecules
chemotrophs convert
inorganic molecules into organic molecules
heterotrophs are the
consumers
almost all heterotrophs depend on _______ for _____ and ____
- phototrophs
- food
- O2
the mesophyll is the
photosynthetic part of leaves
CO2 enters and O2 exits the leaf through the
stoma
the chloroplast is an organelle where
photosynthesis occurs
chloroplasts are mainly found in
mesophyll tissue
what is the grana?
stacks of flattened thylakoid membrane
what is the stroma?
a semi-liquid surrounding thylakoid membranes
what is the thylakoid?
internal membrane of grana
what forms the grana?
the inner membrane of the chloroplasts
what is the photosynthetic equation?
6CO2+12H2O+Light Energy -> C6H12O6 + 6O2 + 6H2O`
the chemical process of photosynthesis is the reverse of
cellular respiration
cells need oxygen to
oxidize organic molecules
plants make….
- cellulose (structure)
- protein in small amounts
- lipids
chloroplasts split H2O into
hydrogen and oxygen
electrons of hydrogen transfer to
sugar molecules
redox is a
oxidation reduction reaction
oxidation is…
the loss of an electron
think breaking down
reduction is…
the gain of an electron
photosynthesis is a
redox process
in a redox process H2O is ______ and CO2 is ______.
- oxidized
- reduced
photosynthesis is a ______ process, with energy provided by….
endergonic
light
in photosynthesis which reactant becomes reduced?
CO2
in photosynthesis which reactant becomes oxidized?
H2O
light reactions happen in the
thylakoids
explain what light reactions do
- split H2O
- release O2
- reduce NADP+ to NADPH
- generate ATP from ADP by photophosphorylation
the calvin cycle is found in the
stoma
the calvin cycle forms _____ from _____ using ____ and ____.
sugar
CO2
ATP and NADPH
the carbon cycle begins with
carbon fixation
what is carbon fixation?
incorporating CO2 into carbohydrate
chloroplasts can be described as
solar-powered chemical factories
thylakoids transform light energy into the chemical energy of
ATP and NADPH
ATP and NADPH powers the synthesis of
carbohydrates
light can be defined as
electromagnetic waves that travel in rhythmic waves
wavelength is
the distance between crests of waves
light consists of discrete particles called
photons
what is the electromagnetic spectrum?
the entire range of electromagnetic energy
pigments are
molecules that absorb visible light
wavelengths that are not absorbed are
reflected or transmitted
the absorption spectrum is a
plot of pigments light absorption vs. wavelength
in chlorophyll a what light works best for photosynthesis?
a violet blue or red
plants reflect which colors
green and yellow
chlorophyll a is…
the main photosynthetic pigment
chlorophyll b is…
an accessory pigment that broadens the spectrum used for photosynthesis
carotenoids are…
accessory pigments that absorb excessive light that would damage chlorophyll
what is a photosystem?
a reaction center complex surrounded by light-harvesting complexes
what are light-harvesting complexes?
they are pigment molecules that transfer energy of photons to the reaction center
what are the two types of photosystems in the thylakoid membrane?
PS II
PS I
photosystem II…
functions first was the second to be discovered
PS I…
function second
the calvin cycle is a ______ reaction
anabolic
linear electron flow involves both _______ and produces _____ and _____ using light energy
photosystems
ATP
NADPH
chemiosmosis is the
diffusion of H+
both chloroplasts and mitochondria generate ATP by
chemiosmosis
chloroplasts transform _____ energy to _____ energy of ATP producing _____.
light
chemical
glucose
mitochondria transfer ______ energy from food and produce ______.
chemical
ATP
polar molecules in high [ ] will ALWAYS attract
H2O
oxygen is released through what part of the plant?
the stomata
ATP and NADPH are both produced where in the plant?
the stroma side
light reactions generate ATP and raise the potential energy of electrons by
moving them from H2O to NADP to produce NADPH
the calvin cycle reduces CO2 to
sugar
carbon enter the cavin cycle as CO2 and leaves as
glyceraldehyde 3-phosphate (G3P)
3 turns of the calvin cycle fixes 3 molecules of CO2 to synthesize
1 G3P
the 3 phases of the carbon cycle are
- carbon fixation
- reduction
- regeneration of CO2 receptor (RuBP)
rubisco is the most important/ abundant…
enzyme that grabs CO2 from the atmosphere and binds it to RuBP
shorter wavelength produce
higher energy
longer wavelengths produce
lower energy
photorespiration consumes _________ and releases _______
O2 and organic fuel
CO2
photorespiration does not produce
ATP or sugar
chloroplasts supply chemical energy and carbon skeletons to synthesize
organic molecules of cells
plants store excess sugar as
starch
besides food production photosynthesis produces…
O2 of our atmosphere
name 4 other organisms besides plants that can carry out photosynthesis
- multicellular alga
- unicellular eukaryotes
- cyanobacteria
- purple sulfur bacteria
stomata is a
collection of pores
