Lec 6 - Photosynthesis Flashcards
Where does photosynthesis take place?
Some prokaryotes and in the chloroplasts of plants and algae
What two processes provide energy for life?
Photosynthesis and cellular respiration
What organisms eat other organisms to get proteins and energy?
Heterotroph (Consumers)
What organisms produce their own food for energy?
Autotrophs (Producers)
What process converts light energy to chemical energy in food?
Photosynthesis
What is the Site of Photosynthesis in Plants?
Chloroplasts
What is the green pigment within chloroplast?
Chlorophyll
Where are chloroplasts found mainly?
in the cells of mesophyll, the interior tissue of leaf
How many chloroplasts does each mesophyll contain?
30 -40
What is the microscopic pores of the leaf where co2 and o2 exit?
Stomata
Where can you find chlorophyll?
Thylakoids
What is the connected sacs in the chloroplast?
thylakoids
What do you call the stack columns of thylakoids?
Grana / granum (singular)
What is the dense interior fluid in chloroplasts?
Stroma
What is this series of reaction called? 6CO2 + 6H2O -> C6H12O6 + 6O2?
Photosynthesis
Photosynthesis is a redox process in which water is _____ and carbon dioxide is ___
oxidized, reduced
Photosynthesis is an______ process; the energy boost is provided by light
endergonic
What are the two stages of Phosyn?
Light-dependent reactions and the calvin Cycle
Light is a form of electromagnetic energy also called?
electromagnetic radiation
What is the distance between crests of waves?
Wavelength
What is the entire range of electromagnetic energy, or radiation?
electromagnetic spectrum
What consists of wavelengths (including those that drive photosynthesis) that produce colors we can see
Visible light
Light also behaves as though it consists of discrete particles, called
Photons
What are substances that absorb visible light?
Pigments
What measures a pigment’s ability to absorb various wavelengths, sends light through pigments and measures the fraction of light transmitted at each wavelength
spectrophometer
What is a graph plotting a pigment’s light absorption versus wavelength
absorption spectrum
The absorption spectrum of chlorophyll a suggests that
violet-blue and red light work best for photosynthesis
What profiles the relative effectiveness of different wavelengths of radiation in driving a process
action spectrum
Who demonstrated the action spectrum of photosynthesis was first in 1883 ?
Theodor
W. Engelmann
What is the main photosynthetic pigment ? What is the accessory pigment that broaden the spctrum used for photosynthesis?
Chlorophyll a and Chlorophyll b
Accessory pigments called ______absorb excessive light that would damage chlorophyll
carotenoids
What is an afterglow that occurs when photons are given off after excited electrons fall back to ground state?
Fluorescence
A ______ consists of a reaction-center complex (a type of protein complex) surrounded by light-harvesting complexes
photosystem
A ______ in the reaction center accepts excited electrons and is reduced as a result
primary electron acceptor
What is the primary pathway, involves both photosystems and produces ATP and NADPH using light energy?
Linear electron flow
What uses only photosystem I and produces ATP, but not NADPH?
Cyclic electron flow
_____ transfer chemical energy from food to ATP; ______transform light energy into the chemical energy of ATP
Mitochondria , chloroplast
What type of photosynthesis uses ATP and NADPH to reduce carbon dioxide to sugar?
Calvin cycle
For net synthesis of 1 G3P, the cycle must take place ______, fixing 3 molecules of carbon dioxide
three times
What are the 3 phases of Calvin cycle?
Carbon Fixation (catalyzed by Rubisco), Reduction, and Regeneration of the carbon dioxide acceptor (RuBP)
In most plants (_____), initial fixation of carbon dioxide, via rubisco, forms a three-carbon compound (3-phosphoglycerate)
(C3 plants)
In _______, rubisco adds oxygen instead of carbon dioxide in the Calvin cycle, producing a two-carbon compound
photorespiration
What type of plants minimize the cost of photorespiration by incorporating carbon dioxide into four-carbon compounds in mesophyll cells
C4 Plants
What plants, including succulents, use crassulacean acid metabolism (CAM) to fix carbon. These plants open their stomata at night, incorporating carbon dioxide into organic acids
Stomata close during the day, and carbon dioxide is released from organic acids and used in the Calvin cycle
CAM plants
Plants store excess sugar as starch in structures such as ___, ____, _____, and ______
roots, tubers, seeds, and fruits
_______ made in the chloroplasts supplies chemical energy and carbon skeletons to synthesize the organic molecules of cells
Sugar
