Which statement is TRUE regarding the light reactions?
A.They rely on energy provided by glucose synthesis.
B. Without photosystem I, photosystem II could not occur.
C. Without water, the system would shut down.
D.Oxygen is required.
E. ATP and NADPH are needed.
C. Without water, the system would shut down.
Which sequence accurately describes the flow of electrons in photosynthesis?
A. H2O → photosystem II → photosystem I → NADP
B. H2O → photosystem I → photosystem II → NADP
C. photosystem I → photosystem II → H2O → NADP
D. photosystem II → photosystem I → NADP → H2O
E. photosystem I → photosystem II → NADP → H2O
A. H2O → photosystem II → photosystem I → NADP
Which of these equations best summarizes photosynthesis?
A. H2O → 2 H+ + 1/2 O2 + 2e-
B. C6H12O6 + 6 O2 → 6 CO2 + 12 H2O
C. 6 CO2 + 6 O2 → C6H12O6 + 6 H2O
D.C6H12O6 + 6 O2 → 6 CO2 + 6 H2O + Energy
E. 6 CO2 + 6 H2O → C6H12O6 + 6 O2
E. 6 CO2 + 6 H2O → C6H12O6 + 6 O2
The light reactions of photosynthesis use _____ and produce _____.
carbon dioxide ... oxygen
A. carbon dioxide ... sugar
B. NADPH ... oxygen
C. NADPH ... NADP+
D. water ... NADPH
D. water ... NADPH
During the light reactions, water is split to produce oxygen. Excited electrons from water join with NADP+ to produce NADPH.
Based on the information provided in this figure, where does the oxygen gas produced by a leaf come from?
H2O
The light reactions of photosynthesis result in which of the following?
A. oxidation of glucose
B. reduction of H2O
C. oxidation of chlorophyll
D. synthesis of ATP
E. oxidation of CO2
D. synthesis of ATP
When discussing photosynthesis, some people mistakenly talk about the light reactions and the dark reactions. Why is "dark reactions" an inaccurate name for the Calvin cycle?
This implies that the Calvin cycle occurs only at night.
Which of the following is generally true about the stratosphere?
A.The dryness level varies with the moon cycle.
B. It is very moist.
C. It is very dry.
D.The dryness level varies with the season.
C. It is very dry.
Based on current findings, which of the following is true?
A. As climate change speeds up, there will be an increase in the number of strong storms, in turn causing an increased amount of ozone depletion.
B. As climate change speeds up, there will be an decrease in the number of strong storms, in turn causing an increased amount of ozone depletion.
A. As climate change speeds up, there will be an increase in the number of strong storms, in turn causing an increased amount of ozone depletion.
Where was the thinning of ozone initially discovered?
A. Over North America
B. Over the Antarctic
C. Over the Arctic
D. Over Europe
B. Over the Antarctic
You are the CEO of a major manufacturing company that decides to use CFCs in production of your products. What are you failing to abide by?
A. Paris Protocol
B. Montreal Protocol
C. Kyoto Protocol
D. Rio Protocol
B. Montreal Protocol
Which of the following two things worked in conjunction to make CFCs harmful to the ozone?
A. fluorine and water vapor
B. fluorine and chlorine
C. water vapor and sunlight
D. chlorine and sunlight
D. chlorine and sunlight
Why do plant leaves appear green?
A. The chlorophyll in the leaves transmits green light.
B. The chlorophyll in leaves reflects green light.
C.The chlorophyll in the leaves absorbs green light.
B. The chlorophyll in leaves reflects green light.
Energy is passed around different chlorophyll molecules until it reaches a specific chlorophyll molecule called the:
A. photoelectric point.
B. reaction center.
C.accessory pigment.
D.nucleus.
B. reaction center.
Why do chloroplasts make energy carriers during the light reactions?
A.to capture the energy of sunlight
B.to do work in the entire cell
C.to create oxygen for the synthesis of sugar
D.to provide energy for the synthesis of sugar
D.to provide energy for the synthesis of sugar
Before photosynthesis evolved, ________ was rare in Earth's atmosphere.
A. N2
B. CO2
C. H2O
D.O2
D.O2
What is the relationship between the light reactions and the Calvin cycle?
A.The light reactions produce oxygen by splitting water. The Calvin cycle produces sugar by fixing CO2.
B.The light reactions produce energy carriers, which are used in the Calvin cycle to convert PGA into G3P.
B.The light reactions produce energy carriers, which are used in the Calvin cycle to convert PGA into G3P.
Carbon fixation involves the addition of carbon dioxide to _____.
A. Rubisco
B.G3P
C. RuBP
D.3-PGA
C. RuBP
In the Calvin cycle, carbon dioxide is added to RuBP
After 3-PGA is phosphorylated, it is reduced by _____.
A. CO2
B. NADPH
C. ATP
B. NADPH
NADPH supplies the electrons that reduce the phosphorylated 3-PGA.
How many carbon dioxide molecules must be added to RuBP to make a single molecule of glucose?
A. 10
B. 2
C. 6
C. 6
Six carbon dioxide molecules are required to produce two G3P molecules, which can be combined to make one glucose molecule.
In the Calvin cycle, how many ATP molecules are required to regenerate RuBP from five G3P molecules?
A. 4
B. 3
C.1
B. 3
Why do plants produce O2?
A.because O2 is produced as a by-product when the plant creates H+ ions and free electrons from water
B. because O2 is produced as a by-product when the plant removes the carbon from CO2
C. because O2 is produced by the plant for later use during respiration
A.because O2 is produced as a by-product when the plant creates H+ ions and free electrons from water
Which of the following equations represents photosynthesis?
A. 6H2O + 6O2 → C6H12O6 + 6CO2
B. 6CO2 + 6H2O → C6H12O6 + 6O2
C. C6H12O6 + 6CO2 → 6O2 + 6H2O
B. 6CO2 + 6H2O → C6H12O6 + 6O2
In which of the following organelles does photosynthesis take place?
A. Ribosome
B. Chloroplast
C. Mitochondrion
B. Chloroplast
What connects the two photosystems in the light reactions?
A. A chain of glucose molecules
B. A thylakoid
C. An electron transport chain
C. An electron transport chain
What two molecules are produced by the light reactions and used to power the Calvin cycle?
A. ATP and NADPH
B. G3P and H2O
C. CO2 and O2
A. ATP and NADPH
What provides the carbon atoms that are incorporated into sugar molecules in the Calvin cycle?
A. RuBP
B. Sucrose (C12H22O11)
C. Carbon dioxide (CO2)
C. Carbon dioxide (CO2)
What transports electrons from the light reactions to the Calvin cycle?
A. NADPH
B. FADH2
C. An electron transport chain
A. NADPH
The light reactions take place in the _________ and the Calvin cycle takes place in the _________.
A. chloroplasts; mitochondria
B. thylakoids; stroma
C. stroma; thylakoids
B. thylakoids; stroma
Consider the scenario of two scientists conducting an experiment to track what happens to the carbon atoms from CO2 molecules used during the Calvin cycle of photosynthesis. They add a radioactive "tag" to the carbon atoms of the CO2 reactants and then collect the products following the reactions. They analyze the products for their level of radioactivity.
Which product(s) would you expect to be radioactive?
Glucose only
Hydrogen ions cross the thylakoid membranes from the stroma by:
A. synthesis.
B. facilitated diffusion.
C. active transport.
C. active transport.
The ATP and NADPH synthesized during the light reactions are:
A. dissolved in the cytoplasm.
B. transported into the nucleus.
C. dissolved in the stroma.
C. dissolved in the stroma.
Imagine that a plant in your garden doesn't receive an adequate amount of water. Which of the following would be most affected by this?
A. the light reactions of photosynthesis only
B. the Calvin cycle of photosynthesis only
C. both the light reactions and the Calvin cycle of photosynthesis
C. both the light reactions and the Calvin cycle of photosynthesis
Enzymes are required during which of the following reactions?
A. the Calvin cycle only
B. the light reactions only
C. both the light reactions and the Calvin cycle
D. neither the light reactions nor the Calvin cycle
C. both the light reactions and the Calvin cycle
All of the following are part of the Calvin cycle EXCEPT:
A. carbon fixation.
B. synthesis of G3P.
C. regeneration of RuBP.
D. generation of ATP.
D. generation of ATP.
Which process of photosynthesis is linked to the production of ATP?
A. splitting of a water molecule
B. fixing of carbon
C. photosystem II
C. photosystem II
What happens to CO2 when it moves into the stroma?
A. The CO2 becomes a by-product of cellular respiration.
B. It becomes a carbohydrate.
C.The CO2 gives up its O2.
B. It becomes a carbohydrate.
Which of the following is most similar to the Calvin cycle?
A. a solar panel converting sunlight into electricity
B. a robot assembling a car
C.a farmer harvesting grain in the fall
B. a robot assembling a car
Which of the following summarizes photosystem I and the electron transport chain I in terms of exergonic and endergonic reactions.
A. The energy of the electron from photosystem II is used to power the exergonic reaction of combining NADP+ with H+.
B. The energy of sunlight is used to power the exergonic reaction of combining NADP+ with H+.
C. The energy of sunlight is used to power the endergonic reaction of combining NADP+ with H+.
C. The energy of sunlight is used to power the endergonic reaction of combining NADP+ with H+.