photosynthesis outline Flashcards
what did van Helmont do? what did he find out?
he planted a 5 lb plant in 200 lbs of soil and gave it H20 for 5 years. the tree gained 165 lbs, but the soil only lost 2 oz. he concluded plant’s mass comes from water, not soil (incorrect)
what did Joseph Priestly do? what did he found out
covered a candle with a closed contained and found that it burned out. but when he added a mint plant to it, the candle continued to burn. he concluded that the mint “restored” the air that the burning candle depleted without knowing of O2
what did Ingenhouse do?
discovered plants needed light, finishing the photosynthesis mystery
what is photosynthesis?
process by which autotrophs use light energy and convert it to chemical energy to make glucose molecules from carbon dioxide and water
where is chemical energy stored?
stored in C-C C-H bonds in glucose
equation for photosynthesis
6CO2 + 6 H2O+ (6 H2O) + light —> 6O2 + (6H20) + C6H1206
what carries out photosynthesis in plants? where are they located?
chloroplasts in green parts of plants
where are most chlorophylls located?
leaves
where do plants get their green color from?
chlorophyll pigment
where is chlorophyll found?
interior layer called mesophyll
where do CO2 and H2O enter plants from?
stomata
disk like sacs
thylakoid
stack of thylakoids
grana
thick fluid inside inner membrane
stroma
where are chlorophyll molecules found?
inside thylakoid membranes
xylum
H2O transport vein
phloem
sucrose transport vein
layers of a leaf
upper epidermis
mesophyll,
guard cell, stomate
lower epidermis
what type of process is photosynthesis?
redox process
what is oxidized and reduced in photosynthesis? what happens as a result?
water - oxidized
carbon dioxide - reduced
electrons gain energy
what provides energy for electrons to go up the energy hill?
light energy captured by chlorophyll molecules
pathway of energy
solar/light energy –> chemical energy/ATP—> energy stored in glucose
what type of energy is sunlight?
radiation or electromagnetic energy
what light can we see?
visible/white light
what happens as light hits a cholorplast?
pigment molecules in the thylakoids absorb different wavelengths of light
what light does chlorophyll a absorb?
mainly blue-violet and red light, and reflects green light
what does chlorophyll b absorb?
mainly blue and orange, and reflects yellow-green
cartenoids
family of orange colored pigments
carrots, tomatoes, fall leaves
what do chlorophyll b and carotenoids do in photosynthesis?
don’t directly participate in the reactions
broaden the range of light a plant can use and then pass the light energy they absorb onto chlorophyll a
what does chlorophyll a do in photosynthesis?
put the energy received to work in photosynthesis
correlation bw wavelength and amount of energy?
inverse
long wavelength=lower energy
short wavelength=high energy
high energy to low
gamma rays (V)
radiowaves (R)
how many stages does does photosynthesis have?
light dependent
light independent
what are the light reactions?
reactions that require light directly
what do light reactions do? what is this known as?
reactions that convert solar energy to chemical energy and produce 1/2 O2 as a waste product
“photo” part of photosynthesis as it takes energy from light
where does the light reactions of photosynthesis occur?
in the thylakoid membrane of the chloroplast’s grana
what does noncyclic phosphorylation use?
light (photo-)
ADP +Pi (phosphorylation)
what are photons?
discrete packets of energy
what can light behave as?
waves or photons
what happens when a pigment molecule absorbs a photon?
one of the pigment’s electrons gains energy
what does the electron that has gained energy do?
raised from the ground state to an excited stae and immediately loses that excess energy as it it unstable
what is the excess energy released as? (3)
heat
fluorescence
passed to primary electron acceptor
fluorescence
light that is emitted as an electron falls from excited to ground state
how are all pigments in the thylakoid membrane grouped?
clusters of 200-300 pigment molecules
what donates electrons to the primary electron acceptor?
only one chlorophyll a molecule
reaction center
chlorophyll a and primary electron acceptor
what does chlorophyll a pigments and other pigments molecules act as?
function together as light gathering antennae that absorb photons and pass the energy along the pigment molecules until it reaches the reaction center