Photosynthesis Flashcards
what is photosynthesis
the conversion of light energy by CO2 and converting to energy
autotrophs
self feeding organisms; they produce their own energy and do not have to go to other organism for energy
phototrophs
self feeding by use of light energy
IE: plants
Heterotrophs
organisms that go to other organisms for energy
IE: humans
chemotrophs
organisms that obtain their energy through the oxidation of inorganic molecules, such as iron and magnesium.
Photosynthesis equation
6CO2 + 12H20 + light energy –> C6H12O2 + 6O2 + 6H2O
Splitting water
a type of hydrolysis, taking place in chlorophyl pigment and produces oxygen as a waste produce
chloroplast
organelles of a plant found in the mesophyll and are the cites of photosynthesis
chlorophyll
give plants green pigment, required to carryout photosynthesis and found in granum
Stomata
they open and close so that CO2 can enter and O2 can exit. Gascious exchange. Regulate water exchange through the release of water vapour.
thylakoid
flatten disk
granum
singular stack of thylakoids
grana
stacks of flatten disk
stroma
similar to cytoplasm
photosynthesis reactants
6CO2 + 12H2O
photosynthesis products
6CH12O6 + 6H2O + 6O2
First stage of photosynthesis (light cycle)
Light reaction occurs in thylakoids. Splitting of water takes place. NADP+ reduces to NADPH and generates ATP from ADP by the process of photophosphorylation. Also releases CO2
Second stage of photosynthesis (calvin cycle)
Occurs in the stroma. When sugar is formed from CO2. The ATP and NADPH from the light cycle get fed into the calvin cycle to make sugar.
- NADPH is the higher electron carrier
Light is a form of electromagnetic energy, also called
electromagnetic radiation. Like other electromagnetic energy, light travels in rythmic waves
Wavelength is
the distance between crests of waves. it determines the type of electromagnetic energy
The electromagnetic spectrum is the
entire range of electromagnetic energy or radiation
Visible light consist of
wavelengths that produce colors we can see
Light also behaves as though it consist of discrete particles called
photons
pigments are
substances that absorb visible light
The color visible to the eye
is the color that is being reflected off the object
objects and substances absorb
pigments
red, blue, and violet are useful for
photosynthesis
chlorophyll a
main photosynthetic pigment, forest green in color
chlorophyll b
accessory pigments, show up as lime green
carotenoids
don’t do much photosynthesis, absorb all the extra light, like a protector, all the other light would be harmful to the chlorophyll, usually orange or yellow
electrons go from a ground state to
an excited (exitation) state, unstable
photosystem
embeded in the thylakoid membrane
reaction center
accepts the sunlighht
primary electron center
final absorption of electrons
light harvesting complexes surround the
reaction center complex, which have a special pair of chlorophyll a molecules
What happens in the photosystems
1 - photons hit the light harvesting complexes
2 - it exits the molecules bumping energy from one chlorophyll to another
3 - then the energy is transffered to one of the special chlorophyl a pair
4 - then that chlorophyl is oxidized
5 - the electron is then absorbed by the primary electron acceptor
photosystem II
functions first and is best at absorbing a wavelength of 680nm. the reaction center chlorophyll a of PS II is called P680
photosystem I
is best at absorbing a wavelength of 700nm. The reaction center chlorophyll of PS I is called P700
From photosystem II 2 electrons fall down the
Electron transport chain to photosystem I. Then the electrons go to NADP+ and the electron make NADPH.
NADP+ is the final
electron acceptor
The splitting of water provides
the electrons
Cyclic electron flow is the absence of
photosystem II
Cyclic electron flow produces
a surpless of ATP, alternative pathway, dont not generate NADPH, and there is no splitting of water.
