Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
36 Cards in this Set
- Front
- Back
Photosynthesis
|
Conversion of light energy to chemical energy that is stored in sugars and other organic compounds.
|
|
Autotrophs
|
Organisms that produce organic molecules from inorganic molecules (CO2, H2O), using energy from the sun.
****Self Feeder. Examples: Green plants, algae, photosynthetic bacteria. |
|
Heterotrophs
|
Organisms incapable of producing their own food, instead living off other organisms or substances produced by them.
|
|
Chloroplast
|
Organelle that absorbs sunlight and uses it to drive the synthesis of organic compounds from CO2 and H2O.
|
|
Stomata
|
Microscopic pores in the leaf that allow CO2 to enter and O2 & water vapor to exit.
Water is absorbed by the roots |
|
Guard Cells
|
Regulate the opening and closing of stomata.
|
|
Stroma
|
Dense fluid found within chloroplasts.
|
|
Thylakoids
|
An elaborate system of interconnected
membranous sacs. |
|
Grana
|
Stacks of thylakoid sacs.
|
|
Chlorophyll
|
Light-energy absorbing green pigment
located within membranes of chloroplasts. |
|
Redox reaction
|
Chemical reaction involving the complete or partial transfer of one or more electrons from one reaction to another.
a) Oxidation – loss of electrons from a substance. b) Reduction – addition of electrons to a substance. |
|
NADP+
(Nicotinamide adenine dinucleotide phosphate): |
An electron carrier that temporarily stores energized electrons produced during the light reaction.
|
|
Light Reaction
|
Reaction which occurs on the thylakoid membranes of chloroplasts, converting solar energy to chemical energy – specifically ATP and NADPH – and releasing oxygen in the process.
|
|
Calvin Cycle
|
Reaction which involves the fixation of atmospheric CO2 and the reduction of fixed carbon into carbohydrates.
|
|
. Photophosphorylation
|
Process of generating ATP from ADP by means of chemiosmosis using a proton-motive force generated across the thylakoid membrane during the light reaction.
|
|
Chemiosmosis
|
energy-coupling mechanism that uses energy stored in the form of a hydrogen ion gradient across a membrane to drive cellular work; process by which most ATP synthesis occurs under aerobic conditions.
|
|
Carbon Fixation
|
Initial incorporation of carbon from CO2 into an organic compound already present in the chloroplast by autotrophs.
|
|
A.Nature of Sunlight: Light
|
is a form of energy known as electromagnetic (EM) energy or radiation. Electromagnetic energy travels in rhythmic waves.
|
|
Wavelength
|
Distance between crests of EM waves.
|
|
EM Spectrum
|
Entire range of EM radiation.
|
|
Visible Light
|
Portion of EM spectrum that can be detected as various colors by the human eye.
|
|
Photon
|
Discrete quantity of light energy that be-haves as if it were a particle; basic unit of light. The amount of energy is inversely related to the wavelength of light – shorter the wavelength, the greater the energy (violet has 2X the amount of energy as red light)
|
|
Pigment
|
Chemical compounds which reflect cer-tain wavelengths of visible light while absorbing other wavelengths of light. Colors we see are reflected by pigments. Colors we don’t see are absorbed by pigments.
|
|
Absorption spectrum
|
Range of a pigment’s ability to absorb various wavelengths of light (chlorophyll). Violet-blue & red (ends of spectrum) are most effective while green (middle of spectrum) is least effective.
|
|
Chlorophyll a
|
Pigment that participates directly in the light reactions, converting solar energy to chemical energy; absorbs blue-violet and red light.
|
|
. Chlorophyll b
|
Accessory pigment that transfers energy to chlorophyll a; absorbs blue and orange light.
a) Also, absorbs and dissipates excessive light energy. |
|
Photosystem
|
Light-capturing unit located in the thylakoid membrane of chloroplast; consists of a reaction-center complex surrounded by numerous light-harvesting complexes.
|
|
Reaction center complex
|
Complex of proteins associated with a special pair of chlorophyll a molecules and a primary electron acceptor.
i)Triggers light reaction of photosynthesis. |
|
Light-harvesting complex
|
Complex of proteins associated with pigment molecules (chlorophyll a, b, and carotenoids) that captures light energy and transfers it to reaction center pigments.
|
|
Primary electron acceptor
|
In thylakoid membrane of chloroplast, specialized molecule that accepts an electron from a pair of chlorophyll a molecules.
i) Passes the electron on to the ETC. |
|
Photosystem II
|
Light-capturing unit in thylakoid membrane of chloroplast; has two molecules of P680 chlorophyll a at its reaction center (red). Absorbs red
|
|
Photosystem I
|
: Light-capturing unit in thylakoid membrane of chloroplast; has two molecules of P700 chlorophyll a at its reaction center (far red). Absorbs dark red
|
|
Linear electron flow
|
Route of electron flow that involves both photo systems and produces ATP, NADPH, and oxygen (net electron flow from H2O to NADP+.
|
|
Cyclic electron flow
|
Route of electron flow that involves only photo system I and produces ATP, but not NADPH or O.
|
|
Calvin Cycle
|
Second of two major stages in photosynthesis, involving the fixation of atm. carbon dioxide and reduction of the fixed car-bon into carbohydrates (glucose). Anabolic process (building carbohydrates from smaller molecules).
|
|
CAM Plants
|
Crussulacean acid metabolism) plants – adaptation for photosynthesis in arid conditions; CO2 entering open stomata at night is converted to organic acids, which release CO2 for the Calvin cycle during the day when stomata are closed.
1.Examples: cactus, pineapple |