There are two types of plants C3 and C4 plants. In C3plants, Ribulose bisphosphate can fix carbon as explained in thismodule leading to the formation of 3- Phosphoglycerate andeventually formation of sugar through the Calvin cycle. Ribulosebisphosphate is also able to catalyze the reaction in which oxygenis transformed into glycolate which eventually forms CO2 (a processcalled photorespiration). Therefore, in C3 plants, oxygen andcarbon dioxide compete for RuBP. In C4 plants, carbon dioxideinitially reacts with phosphoenol pyruvate to make malate andoxaloacetate. The products of this reaction are then able to travelto an inner compartment of the leaf that contains RuBP and sugar iseventually made. Since RuBP is contained in an inner compartment,oxygen is not able to react with it.
(1) Why are C4 plants able to continue photosynthesiseven at low CO2 levels.
(2) Would you expect the greenhouseeffect (an increase in CO2 content of the atmosphere) to have agreater effect on C3 or C4 plants? Why?
There are two types of plants C3 and C4 plants. In C3plants, Ribulose bisphosphate can fix carbon as explained in thismodule leading to the formation of 3- Phosphoglycerate andeventually formation of sugar through the Calvin cycle. Ribulosebisphosphate is also able to catalyze the reaction in which oxygenis transformed into glycolate which eventually forms CO2 (a processcalled photorespiration). Therefore, in C3 plants, oxygen andcarbon dioxide compete for RuBP. In C4 plants, carbon dioxideinitially reacts with phosphoenol pyruvate to make malate andoxaloacetate. The products of this reaction are then able to travelto an inner compartment of the leaf that contains RuBP and sugar iseventually made. Since RuBP is contained in an inner compartment,oxygen is not able to react with it.
(1) Why are C4 plants able to continue photosynthesiseven at low CO2 levels.
(2) Would you expect the greenhouseeffect (an increase in CO2 content of the atmosphere) to have agreater effect on C3 or C4 plants? Why?
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Review question its 1-12 sorry for the xtra questions in the bottom 1:2D chromatography is so named because ____ A: there are two steps: labeling with a radioactive marker and separation via chromatography B: two different solutions are used in the paper chromatography C: the molecules are separated into a linear arrangement, meaning two dimension D: two different types of radioactive markers must be used E: the process separates the molecules in two direction, first along the X and then along the Y axis 2: :Which molecule(s) regulate(s) photosynthesis by sensing the metabolic status of the chloroplast and regulating proton flow out of the thylakoid lumen?? A: ATP synthase B: antenna complex C: Chrolophyll B D: carotenoids E: chlorphyll A 3: When does A CAM plant take in atmospheric CO2? A: daytime only B: Summer day C: winter day D: nighttime only E: anytime the calvin cycle is happening 4: Where can you find ATP synthase in a plant cell ? B: in the mitochondial inner membrane C: both thylakid and inner mitochondria membrane D: only in the nucleus E: embedded in the plasma membrane 5: chloroplast kept in the daek can continue to make sugar is provided with A: NADPH, CO2, and ADP B: CO2, and ATP C: NADPH, ATP, and CO2 D: NADPH and ATP E: water and ATP 7: C3 plants are more susceptible to photorespiration than either C4 or CAM plants. Why do most plants lack the C4 pathway?? A: Switching between C3, C4, and CAM photosynthesis is very difficult for most plants B: ?Rubisco is more efficient in C3 plants when compared to rubisco of C4 and CAM plants C: Most plant species do not have vacuoles in their cells to store the malate generated from CO2 taken in during the night. D; : Photorespiration is not a serious problem for most plants.? E: There is an energetic cost to C4 and CAM pathways that only makes them advantageous in very hot and/or arid environments.? 8: In Engelmann's classic experiment, why were the oxygen-requiring bacteria clustered around the regions of Spirogyra algae that were bathed in red, blue, and violet light? A; The bacteria were immobile and that is where Engelmann happened to place them .? B; The most energy-rich wavelengths of light are found at the edges of visible and nonvisible light (ultra violet and infrared) C; Photosynthesis is most active in those wavelengths of light and thus more oxygen is consumed by the algae in those regions. D: Photosynthesis is most active in those wavelengths of light and thus more oxygen is produced by the algae in those regions.? E: : Chlorophyll is green and thus reflects green light. 9: In any experiment, changes to the dependent variable based on the manipulations of the independent variable are measured. When determining the action spectrum of a given plant, what is the independent variable and what is the dependent variable? A: independent = rate of O2 release in photosynthesis; dependent = wavelength? B: ?independent = absorption of light; dependent = wavelength C: independent = wavelength; dependent = rate of O2 release in photosynthesis? D: independent = wavelength; dependent = absorption of light? E: independent = rate of O2 release in photosynthesis; dependent = absorption of light 10: Which plant structure is responsible for gas exchange?? A: stromal lamellae B: grana C: granastomata? D: stroma 11: n order to elucidate the Calvin cycle, Calvin and his colleagues used two-dimensional paper chromatography to analyze the presence of different molecules under different conditions. What did they conclude from the accumulation of RuBP when CO2 levels were low?? A: CO2 serves as a non-competitive inhibitor of rubisco. B: RuBP is the last substrate to react in the Calvin cycle. C: RuBP only reacts with CO2 when concentrations of ATP are low D: RuBP is the first substrate to react with CO2 E: ?RuBP only reacts with CO2 in the sunlight. 12: Why isn't oxygen produced by organisms that perform anoxygenic photosynthesis? A; their membranes lack ATP synthase? B; They use a different enzyme for the initial reactions of the calvin cycle C: they use electrons donors other than water D: their photosystem do not utilize the calvin cycle E: their chorophyll contains an iron rather than magnesium A: ?there are two steps: labeling with a radioactive marker and separation via chromatography |
B: two different solutions are used in the paper chromatography process? |
C: the molecules are separated into a linear arrangement, meaning two dimensions? |
D: two different types of radioactive markers must be used? |
E: the process separates the molecules in two directions, first along the x axis and then along the y axis? |
2:Which molecule(s) regulate(s) photosynthesis by sensing the metabolic status of the chloroplast and regulating proton flow out of the thylakoid lumen??
A: ?ATP synthase |
B: the antenna complex? |
C: chlorophyll b? |
D: carotenoids? |
E: chlorophyll a 3: When does a CAM plant take in atmospheric CO2??
6: Where does the Calvin cycle occur?
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7: C3 plants are more susceptible to photorespiration than either C4 or CAM plants. Why do most plants lack the C4 pathway??
A: Switching between C3, C4, and CAM photosynthesis is very difficult for most plants.? |
B: ?Rubisco is more efficient in C3 plants when compared to rubisco of C4 and CAM plants. |
C: Most plant species do not have vacuoles in their cells to store the malate generated from CO2 taken in during the night.? |
D: Photorespiration is not a serious problem for most plants.? |
E: There is an energetic cost to C4 and CAM pathways that only makes them advantageous in very hot and/or arid environments.? |
8: In Engelmann's classic experiment, why were the oxygen-requiring bacteria clustered around the regions of Spirogyra algae that were bathed in red, blue, and violet light??
A:The bacteria were immobile and that is where Engelmann happened to place them.? |
B: The most energy-rich wavelengths of light are found at the edges of visible and nonvisible light (ultra violet and infrared).? |
?c: Photosynthesis is most active in those wavelengths of light and thus more oxygen is consumed by the algae in those regions. |
D; Photosynthesis is most active in those wavelengths of light and thus more oxygen is produced by the algae in those regions.? |
?e: Chlorophyll is green and thus reflects green light. |
9; In any experiment, changes to the dependent variable based on the manipulations of the independent variable are measured. When determining the action spectrum of a given plant, what is the independent variable and what is the dependent variable??
A: independent = rate of O2 release in photosynthesis; dependent = wavelength? |
B: ?independent = absorption of light; dependent = wavelength |
C: independent = wavelength; dependent = rate of O2 release in photosynthesis? |
D: independent = wavelength; dependent = absorption of light? |
E: independent = rate of O2 release in photosynthesis; dependent = absorption of light? |
10: Which plant structure is responsible for gas exchange??
A: stromal lamellae? |
B: grana? |
C: stomata? |
?D: stroma 11: In order to elucidate the Calvin cycle, Calvin and his colleagues used two-dimensional paper chromatography to analyze the presence of different molecules under different conditions. What did they conclude from the accumulation of RuBP when CO2 levels were low??
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