Exam 3_Openstax Chapter 5 Flashcards
Mesophyll
the middle layer of a leaf where photosynthesis takes place.
Stomata
where gas exchange of CO2 and oxygen takes place
Photosynthesis in all autotrophic eukaryotes take place in the …?
Chloroplast
Thylakoids
Granum
Stroma
Are stomata located on the upper epidermis or lower epidermis?
Lower
Photosynthesis takes place in two stages:
the light-dependent reactions and the Calvin cycle.
What happens in light-dependent reactions.
takes place in thylakoid membrane, chlorophyll absorbs energy from sunlight and then converts it into chemical energy with the use of water.
What is the by product of the light dependent reaction?
oxygen, from the hydrolysis of water as a byproduct
Where does the Calvin cycle take place?
The stroma
What happens in the Calvin cycle?
the chemical energy derived from the light-dependent reactions drives both the capture of carbon in carbon dioxide molecules and the subsequent assembly of sugar molecules.
What do the light-dependent reactions and the Calvin cycle use to transport the energy from one to the other?
carrier molecules
Wavelength
distance between two similar points in a wave, like crest to crest
Electromagnetic Spectrum
the range of all possible wavelength of radiation.
What kind of light do pigment molecules absorb in photosynthesis?
Visible light
Do pigments absorb or reflect the color of light they cannot absorb?
they reflect
Chlorophylla à
green color, most common pigment in photosynthetic organisms
What colors do chlorophyll a absorb?
blue and red
What kind of light does Chlorophyll b absorb?
blue and red-orange light
Absorption Spectrum
the color of light that a type of pigment absorbs
The light dependent reaction creates energy that is used to make what in the Calvin cycle?
Sugar molecules
What are the photosystems composed of?
pigment molecules and proteins
Where do photosystems exist?
membranes of thylakoids
How many photons is absorbed by a pigment molecule in the photosystem?
1
What is considered a packet of light energy in a photsystem?
a photon
Where does photon travel to?
a molecule of chlorophyll
After a photon excites an electron in chlorophyll, what happens?
Chlorophyll donates an electron
what is the purpose of light-dependent reactions?
to convert solar energy into chemical carriers used in the Calvin cycle
how many photosystems exist in eukarya and prokarya?
2
when photon hits, photosystem 2 transfers the free electron to the…
electron transport chain
Where do hydrogen ions move from?
From the Stroma into the thylakoid space.
Where does the electron finally get accepted to after fueling the membrane hydrogen pumps.
a pigment molecule in the next photosystem, which is photosystem 1
From photosystem II, the electron travels along…?
a series of proteins
In light dependent reactions, energy absorbed by sunlight is stored by two types of energy-carrier molecules, what are they?
ATP and NADPH
Energy is store in a bond for ATP, what molecule is ATP bonded to?
phosphate group
Energy is store in a bond for NADPH, what molecule is NADPH bonded to?
hydrogen atom
What part of photosynthesis do ATP and NADPH release their bonds?
The Calvin Cycle
What do ATP and NADPH tranform into after releasing their energy in the Calvin cycle.
ADP and NADP^+
What is the chemiosmosis?
the flow of hydrogen ions through ATP synthase
What is photophorylation
the process of attaching a third phosphate to ADP
After the hydrogen ions pass throught the thylakoid membrane, where do they pass through next?
the embedded protein complex called ATP synthase
When the electron arrives at photosystem 1, it re-energnized by another ___?
proton
After the electron has been re-energized by a proton in photosystem 1, what happens?
Formation of NADPH
What for is ATP and NADPH made in photosynthesis used for?
the formation of carbohydrate molecules
Define the Calvin cycle:
the reaction of photosynthesis used to form glucose and other carbs
CO2 enters the leaf through what part of the leaf?
the stomata
After the CO2 passes through the stomata where do they go next?
Into the mesophyll cells and then the stroma of the chloroplasts
What is the site of the Calvin cycle where sugar are synthesized?
the chloroplasts
What are the three basic stages of the Calvin cycle?
fixation, reduction, and regeneration
What other chemicals in the stroma beside CO2 are present in the Calvin cycle?
RuBisCO and RuBP
What does RuBP stand for?
the molecule ribulose bisphosphate
What atoms is RuBP composed of?
five atoms of carbon and a phosphate group on each end
RuBisCO catalyzes a reaction what?
Between CO2 and RuBP
CO2 and RuBP form what?
a six carbon compound that is then turned to three carbon compounds
What process is called carbon fixation?
when the six carbon is immediated turned into three carbon compounds
Why is it called carbon fixation?
because CO2 is fixed from being inorganic to organic molecules
What is the 3 carbon compound int eh Calvin cycle called?
3-PGA
what happens to 3-PGA?
it’s converted to another carbon compound called G3P
What molecules are use to converter 3-PGA into it’s next carbon compound?
ATP and NADPH
What type of reaction is called the reduction reaction?
the conversion of 3-PGA to G3P
Why is it called the reduction reaction in the calvin cycle?
because ADP and NAD+ form and therefore need to be re-energized
How many turns of the Calvin cycle to fix six carbon atoms from CO2?
six turns
The six turns in the Calvin cycle require how many molecules of ATP and NADPH?
12 ATP and 12 NADPH in reduction, and 6 ATP in the regeneration step.