BIOL 150 Ch8-SM/SD
A key role of PSI is to produce high-energy electrons that are used to make
NADPH
During the Calvin cycle, high-energy electrons are provided by_____and the source of energy for the reactions is______
NADPH; ATP
Which of the following organisms can carry out photosynthesis?
- Algae - Bacteria - Plants
Photosynthesis is a redox reaction. Which of the following statements are true?
- Carbon dioxide is reduced. - Water is oxidized.
Which of the following are products of the light reactions of photosynthesis that are used as reactants in the Calvin cycle?
- NADPH - ATP
Which of the following are major chemical products of the light reactions of photosynthesis?
- NADPH - Oxygen - ATP
Photosynthesis is a redox reaction. Which of the following statements are true?
- Water is oxidized. - Carbon dioxide is reduced.
Living organisms that are not plants depend on photosynthesis because photosynthesis produces: (1) organic molecules such as_____that can be used for nourishment; and (2) the____gas that makes up a large portion of the Earth's atmosphere.
- carbohydrates - oxygen
The energy released as electrons pass from an electron carrier to another in the electron transport chain between photosystem II and photosystem I is used to
- establish an electrochemical gradient - pump H+
Why is photorespiration considered wasteful?
-It reduces the ability of a plant to make carbohydrates. - It reverses the effects of photosynthesis.
The steps of the light reactions of photosynthesis yield three major products:
-NADPH - ATP - Oxygen
The G3P produced at the end of the second phase of the Calvin cycle is directly used for which of the following
-To regenerate ribulose bisphosphate - To make glucose or other carbohydrates
What is the product of the carbon fixation reaction catalyzed by rubisco in the Calvin cycle
3-phosphoglycerate
What is the product of the oxidation of water during photosynthesis
O2
What enzyme is responsible for carbon fixation
Rubisco
Why are carbohydrates critical for plant cells?
They provide a source of energy and form the precursors for most organic macromolecules.
In cyanobacteria, the Calvin cycle occurs in the____of cells
cytosol
true or false: photosynthetic bacteria have chlorophyll embedded in their chloroplast
false
The electrochemical gradient generated in the light reactions of photosynthesis is used primarily to
generate ATP via ATP synthase
what high energy molecule is the final product of photosynthesis
glucose
The process of photorespiration is wasteful because
it releases carbon dioxide from organic molecules, thus limiting plant growth
O2 is produced in the thylakoid lumen via the
oxidation of water in photosystem II
a particle of light is a
photon
In hot dry conditions, rubisco can attach O2 to RuBP in a process called_____which ultimately produces CO2.
photorespiration
A molecule that can absorb light energy is called a(n)
pigment
atrazine is a chemical that blocks the electron from leaving photosystem 11. what would be the immediate effect on the plant
prevents ATP synthesis
In photosynthesis, carbon dioxide is reduced and H2A is oxidized. What type of chemical reaction is this?
redox reaction
In the Calvin cycle, CO2 is____
reduced
During photosynthesis, oxygen is produced by the
removal of electrons from water in PSII
What enzyme is responsible for carbon fixation?
rubisco
The reactions of the Calvin cycle occur in the____
stroma
Chlorophylls a and b are found bound to integral membrane proteins in the______membrane of the chloroplast.
thylakoid
Where do the light reactions occur?
thylakoid membrane
where is the chlorophyll located in a plant
thylakoid membrane
The light reactions of photosynthesis take place in the_____membrane, while the Calvin cycle occurs in the_____of the chloroplast.
thylakoid; stroma
true or false: the end product of photosynthesis is the starting material of cellular respiration
true
The electrons that exit PSII are replenished by electrons from oxidized_____, which yields oxygen gas that can be used by plant cells or released to the environment.
water
Within a chloroplast, where is the stroma located?
Between the thylakoid membrane and the inner membrane
What molecule is reduced in the Calvin cycle
CO2
What part of photosynthesis is best described as "a series of energy changes"
The light reactions
The Calvin cycle uses energy from_____, and high-energy____supplied by NADPH.
ATP; electrons
During photosynthesis, NADPH is synthesized by
Photosystem 1
The end product of phase 2 of the Calvin cycle is G3P. This molecule is used to synthesize_____and to regenerate the starting material_____bisphosphate.
carbohydrates; RuBP
The source of carbon for the carbohydrates synthesized in the Calvin cycle is____in the atmosphere
carbon dioxide
what is the function of rubisco
carbon fixation
