light-dependent reactions
The first stage in photosynthesis, occuring the presence of light. The light captured is used in the production of ATP
light-independent reactions
These are chemical reactions that convert carbon-dioxide to glucose (organic moles)
action spectrum
A spectrum of photosynthesis that shows the percentage of light used for photosynthesis depending on different wavelengths (nm).
absorption spectrum
electromagnetic spectrum transmitted through a substance, showing wavelengths
wavelength
Each color is composed of different _______ and frequencies. Allows us to scientifically identify different colored lights. The unit of measure is nm.
nm
one-billionth of a meteter; unit of measurement
nanometer
it is a unit of measurement; one billionth of a meter
photosynthesis
It is the process of converting water, carbon dioxide and light energy to oxygen and ATP (from light energy to chemical energy)
violet-blue
The color with wavelengths of around 200nm to 500nm. Around 70 to 90 percent of this type of light is absorbed by both chlorophyll 'a' and 'b'.
green-yellow
The photosynthesis that occurs here is due to accessory pigment (carotene/xathophll); Lowest % use of light in photosynthesis;(500nm - 600nm)
orange-red
Photosynthesis occurs here when the wavelength is around 650nm-750nm. At around 60%, this light acts, and at around 40-50%, this type of light is absorbed by chlorophyll a and b.
chlorophyll
The green pigment inside a thylakoid that activates from light energy, and is the main phtotsynthetic pigment.
chlorophyll a
Green pigment- does not absorb green light waves. It is the only pigment that can actually participate directly in the light reactions
chlorophyll b
Example of an accessory pigment that is green.
absorption
To take in
xanthophyll
Pigment that causes photosynthesis when the wavelength of light 500-600nm (green/yellow)
carotene
Accessory pigment in plants that helps absorb red/orange light
visible light
spectrum you can see (ROYGBIV)
photoactivation
Photoactiavtion occurs when chlorophyll molecules absorb light, the energy from the light rasies electrons to a high energy state
photosystem I
the "back-up" photosystem in case of a lack of NADP+ due to the excessive accumulation of NADPH (when there is a limiting factor); cyclic photophosphorylation because the electrons are transported along the proton gradient in a cyclic manner; it provides an alternative pathway of electrons to allow ATP production
photosystem II
It is a back up system involved in cyclic photophosphorylation when there is not enough NADH.
non-cyclic photophosphorylation
producing ATP using energy from an excited electron from photosystem (straight line), this is in the presence of light adding phosphate to ADP to make ATP
cyclic photophosphorylation
Cyclic Phopsporilation is the process of electrons running through photosystem 2 and creating a proton gradient, and it is called cyclic because it keeps going through a cycle, and does not end, like electrons running through photosystem 1. Electrons that go through photosystem 2 only enter when there are limiting factors in order to keep establishing the proton gradient. The continuous cycle of electrons moving creates a gradient and ATP and NADPH can be made again.
ATP
Produced as a result of the high concentrations of the protons
ADP
Converted to ATP with the help of ATP synthase
NADPH
NAD is a coenzyme and also works as a carrier it carries an ion from one reaction to another. NAD carries a phosphate and forms NADP at a point then it realeases ADP to convert ATP. Hydogen from the split of water molecules also bind to NADP and forms NADPH. Then NADPH goes to the Calvin cycle, the hydrogen are then released and then goes back to NADPand used to produce carbohydrates in the Calvin cycle.
NADP+
NADP+ temporarily stores the energized electrons.
H+
H+ ions are pumped across a membrane to provide ATP for photosynthesis.
thylakoid
Area where light-dependent reaction occurs, and is arranged in stacks in the chloroplast.
thylakoid membrane
Area between the stroma and lumen where the Hydrogen (proton) passes through and helps the ADP+P convert to ATP
stroma
The thick fluid between the granum which supports the cell
thylakoid space
space bound the membrane of the thylakoid organelle in the chloroplasts and contains pigments for absorption of light
e-
The flow of electrons causes protons to be pumped into the thylakoid space.
water
the source of oxygen in the light-dependent reactions
oxygen
A product of photosynthesis; waste product; the source is water
photolysis
The splitting of water molcules
Calvin cycle
Light independent reaction that occurs in three steps: carbon fixation, reduction, and regeneration of RuBP
carbon fixation
the combining of ribulose biphosphate and carbon dioxide to form a temporary 6 carbon molecule. Also known as caboxylation reaction.
rubisco
One of the main players in the Calvin Cycle. The enxyme that catalyzes the reaction of carbon fixation of carbon dioxide and ribulose bisphosphate. This enxyme is also known as ribulose trisphosphate carboxylase.
ribulose bisphosphate
Organic substance that is part of photosynthesis. Catalyzes reaction between RuBP with CO2.
carbon dioxide
One of the limiting factors; without this the amount of glycerate 3-phosphate produced is limited.
GP
Another way to say glycerate-3 triphosphate. It is the product of the splitting of the temporary 6 carbon compound found in the calvin cycle. It gets converted into triose phosphate.
TP
For every 6 molecules of this, 5 will be used to regenerate RuBP and one will be used to produce glucose phosphate
glycerate 3-phosphate
A non-abbreviated term for GP; a product of the carbon fixing that occurs to the Rubisco Biphosphate (RuBP), joins to form a temporary 6 carbon combound in the calvin cycle. Later, becomes converted into triose phosphate.
triose phosphate
A molecule that is generated through the Calvin Cycle. Ribulose Biphosphate goes through the the carboxylation reaction, producing glycerate-3-phosphate as a result. Through the reduction reaction of glycerate-3-phosphate, this molecule is made. For every 6 of these molecules, 5 will be used to regenerae RuBP and 1 will be used to produce glucose phosphate.
glucose phosphate
After the production of triose phosphate, glucose phosphate is produced. this happens because for every 6 molecules of triose phosphate, 5 will be used to regenerate Rubisco Biphosphate while 1 will be used to produce this glucose phosphate molecule. This molecule is important because the energy source for plants, starch, is produced by the condensation reaction of many glucose phosphate molecules combined.
reduction
Gain of electrons
granum
Stacks of thylakoids
starch grain
inside the chloroplast carrying the function of storing the glucose that was produced from the calvin cycle
limiting factor
Temperature, Carbon Dioxide and light intensity affects the rate of photosynthesis
rate-limiting step
The slowest step of the photosynthesis reaction; decreases the rate of photosynthesis as a whole; determined by external environmental factors (limiting factors) such as temperature, CO2 concentration and light intensity
temperature
One of the limiting factors that slows down the process of the Calvin Cycle by inhibiting the enxzymes. The rate limiting step affected by this limiting factor is the point where carbon dioxide is fixed.
light intensity
One of the limiting factors; when this is poor, there is a shortage of ATP and NADP. Without these products, the light independent reactions can't occur as glycerate 3-phosphate cannot be reduced. Therefore a shortage of these products will limit the rate of photosynthesis.