2017 Photosynthesis Respiration MCQ QP+MS

2017 Respiration and Photosynthesis MCQ2017 / H2 / ACJC PRELIM / P1 Q201Which of the following statements explains the mechanism for chemiosmosis in the synthesis of ATP?AThe energy released by the reduction and subsequent oxidation of components of the electron transport chain is transferred to ATP synthase for the synthesis of ATP.BPhosphorylation of ADP is linked to the proton gradient established by the electron transport chain.CThe difference in pH between the intermembrane space and the cytosol drives the formation of ATP.DThe flow of H+ through ATP synthase into the intermembrane space drives the synthesis of ATP.2017 / H2 / ACJC PRELIM / P1 Q212The diagram below shows the rate of photosynthesis of four different plants at different concentrations of carbon dioxide.200530Rate of CO2 uptake / cm3m-2h-1 CO2 Concentration / µl l-1 Which of the following conclusions can be made?1At CO2 concentrations below 150 µl l-1, CO2 concentration is the main limiting factor for all the plants.2CO2 compensation point is around 40 µl l-1 for sunflower and red clover, and it measures the light intensity when the rate of CO2 uptake equals to the rate of CO2 given off.3Rate of CO2 uptake was zero for maize at CO2 concentration of 0 µl l-1 as the amount of CO2 released from respiration is used for photosynthesis.

4Of the four plants, maple has the lowest amount of organic compound produced at CO2 concentration of 200 µl l-1.A1, 2 and 3 onlyB1, 3 and 4 onlyC1 and 2 onlyD3 and 4 only2017 / H2 / ACJC PRELIM / P1 Q223Dinitrophenol is a metabolic poison that can lodge within the thylakoid membranes of chloroplasts. It then provides an alternative route for H+ ions to diffuse across the thylakoid membranes. In what way will the Calvin cycle be affected in chloroplasts poisoned by dinitrophenol?ANo change in rate as Calvin cycle occurs in the stroma and not at thylakoid membranes.BThe rate of Calvin cycle will increase as pH in the stroma will decrease towards the optimum for enzymes involved in the cycle.CThe rate of Calvin cycle will decrease with the accumulation of glycerate-3-phosphate.DThe rate of Calvin cycle will decrease with the accumulation of glyceraldehyde-3-phosphate.2017 / H2 / AJC PRELIM / P1 Q184Which of the following is true about both cyclic and non-cyclic photophosphorylation?1Establishes an electrochemical gradient across the thylakoid membrane 2Involve photosystem II3Require oxygen as the final electron acceptor 4Photolysis of water occurs A1 onlyB1 and 2 onlyC2 and 4 onlyD1, 3 and 4 only

2017 / H2 / AJC PRELIM / P1 Q195The experimental setup below was created by homogenizing leaf cells to break their cell walls. The leaf suspensions containing the cytoplasm and organelles were then placed in test-tubes containing non-labeled water (H216O) and 18O-labeled water (H218O) respectively. A few drops of DCPIP, a hydrogen acceptor, were added to each test-tube. DCPIP will turn from blue to colourless when it is reduced and this colourless DCPIP can be reoxidized to blue. The test-tubes were then exposed to blue light for 30 minutes. Which of the following shows the results of the two test-tubes after 30 minutes?Tube ATube BGas evolvedDCPIP colourGas evolvedDCPIP colourAC16O2BlueC18O2BlueB16O2Blue16O2BlueCC16O2ColourlessC18O2ColourlessD16O2Colourless18O2Colourless2017 / H2 / AJC PRELIM / P1 Q206From which substrate is the first carbon dioxide molecule released during cellular respiration?AGlucoseBPyruvateCAcetyl-coADCitrate

2017 / H2 / ACJC PRELIM / P1 Q217Four tubes containing preparations from animal tissue were set up as shown in the table.Tube Contents1234Glucose + homogenized cells Glucose + cytoplasm lacking organellesPyruvic acid + homogenized cells Pyruvic acid + mitochondria After incubation, in which tube/ tubes would at least 36 ATP be produced?A1 onlyB1 and 3 onlyC1, 2 and 4 onlyD1, 3 and 4 only2017 / H2 / CJC PRELIM / P1 Q228Sodium azide is a strong inhibitor to the ETC in mitochondria. An experiment was conducted with isolated mitochondria, 2 molecules of glucose, 10 molecules of pyruvic acid along with oxygen, ADP and NAD+ which was supplied in excess. What would be the expected production of ATP from the experiment? A2B4C10D222017 / H2 / CJC PRELIM / P1 Q239Which of the following is not true of photosynthesis.AThe spectra of light in which photosynthesis is most efficient is in the red and violet region.BRate of ATP synthesis depends on the differential proton gradient across the thylakoid membrane. CPhotosynthesis starts first with the photolysis of water.DOxygen concentration affects the efficiency of the light independent reaction.

2017 / H2 / DHS PRELIM / P1 Q2310The graph shows the results of increased concentrations of carbon dioxide on soy bean photosynthesis at various leaf temperatures. Carbon dioxide concentration is measured in ppm (parts per million). Light intensity was at an optimum level. Which conclusion concerning the data in the graph is valid?AAt all temperatures up to 15ºC, carbon dioxide concentration is limiting. Above 15ºC, temperature becomes the limiting factor. BSupplementing plants with carbon dioxide is only effective at temperatures above 25ºC.CThe photosynthetic rate obtained at the optimum temperature for 370ppm CO2 could be achieved at a temperature 5ºC lower using an increased concentration of CO2. DWhen light intensity and temperature are limiting, increased carbon dioxide concentration increases the rate of photosynthesis. 2017 / H2 / DHS PRELIM / P1 Q2411Some apples can be stored in controlled atmospheric conditions for up to a year. Taste and texture are maintained by using conditions that reduce the production of a fruit-ripening plant hormone while limiting the build-up of ethanol. Ethanol damages the fruit.The storage conditions needed include low temperature (1ºC), high carbon dioxide concentration (1.2%) and low oxygen concentration (0.9%).Why are these conditions needed?1Low oxygen concentration favours anaerobic respiration.2Enzyme activity is reduced.

3Conversion of sugar to ethanol is minimised.4High carbon dioxide concentration promotes photosynthesis. A1, 2 and 3B1, 2 and 4C2 and 3 onlyD3 and 4 only2017 / H2 / JJC PRELIM / P1 Q2212Isolated chloroplasts, suspended in buffer solution, are often used to study the light dependent stage of photosynthesis.During this stage, electrons (e-) are transferred by carriers and provide energy so that a proton (H+) gradient can be formed. Protons diffuse through membrane proteins that are linked to synthase enzymes. Three compounds that can be added to isolated chloroplasts are:1DCMU, which inactivates a carrier that accepts electrons from photosystem II2DCPIP, which can act as a final electron acceptor3ammonium hydroxide solution, which absorbs protonsWhich compounds, when added separately to isolated chloroplasts, would allow the light dependent stage of photosynthesis to occur and which would inhibit it?allowinhibitA12 and 3B1 and 32C21 and 3D2 and 31

2017 / H2 / JJC PRELIM / P1 Q2313The rate of photosynthesis in pondweed was measured when one variable was changed and all others were standardised.The graph shows the rate of photosynthesis at different values of a variable, X. Which variables could be represented by X? 1carbon dioxide availability2light intensity3oxygen availability4temperature5leaf area exposed to direct lightA1, 2 and 5B1 and 2 onlyC2, 4 and 5D3 and 4

2017 / H2 / JJC PRELIM / P1 Q2414The diagram below shows the link reaction and stages of the Krebs cycle. Which molecules are represented by the letters W, X, Y and Z? WXYZAacetyl CoAcarbon dioxideADPpyruvateBpyruvateacetyl CoAcarbon dioxideADPCADPcarbon dioxideacetyl CoApyruvateDacetyl CoApyruvatecarbon dioxideADP2017 / H2 / MJC PRELIM / P1 Q20QUESTION 15Which of the following statement(s) is/are true with regards to cyclic and non-cyclic photophosphorylation?1Only cyclic photophosphorylation produces oxygen.2Only cyclic photophosphorylation can function in the abs