Photosynthesis — Paper 2 · IGCSE Biology (9-1) 0970

11 The equation for photosynthesis is shown. … 1 … + … 2 … → glucose + … 3 … Which words correctly complete gaps 1, 2 and 3? 1 2 3 A carbon dioxide light oxygen B carbon dioxide water oxygen C oxygen light carbon dioxide D oxygen water carbon dioxide

1 marks

Answer: B

This question in 0970/21 May/June 2018

11 An experiment was carried out using the apparatus shown. The carbon dioxide content of the water in each test-tube was measured at the start and again three hours later. In which test-tube would there be a decrease in carbon dioxide content? A B C D black polythene water to keep out light light light light water plant water snail

1 marks

Answer: C

This question in 0970/22 Oct/Nov 2018

11 The diagram shows an experiment to investigate the balance between respiration and photosynthesis. In which tube are photosynthesis and respiration taking place at the same time? A B C D black water polythene to keep snail out light light light light pond weed

1 marks

Answer: C

This question in 0970/21 May/June 2019

1 Carbon dioxide diffuses into a leaf. Which characteristic of living things requires this? A excretion B movement C nutrition D respiration

1 marks

Answer: C

This question in 0970/22 May/June 2019

11 The diagram shows an experiment to investigate the balance between respiration and photosynthesis. In which tube are photosynthesis and respiration taking place at the same time? A B C D black water polythene to keep snail out light light light light pond weed

1 marks

Answer: C

This question in 0970/22 May/June 2019

12 Some gardeners use Epsom salts (magnesium sulfate) as a fertiliser for their plants. Epsom salts release magnesium ions into the soil. How would this benefit the plants? A prevents pests from eating the leaves B prevents the leaves from going yellow C prevents water loss from the leaves D prevents the growth of weeds

1 marks

Answer: B

This question in 0970/22 May/June 2019

10 The diagram shows an experiment investigating the effect of light intensity on an aquatic plant. light light source source 20 cm 10 cm P Q Photosynthesis occurred in both test-tube P and test-tube Q. Both test-tubes were kept at the same temperature. The number of bubbles produced in test-tube P was 12 bubbles per minute. What is the most likely number of bubbles produced in one minute in test-tube Q? A 0 B 3 C 12 D 48

1 marks

Answer: D

This question in 0970/22 Oct/Nov 2019

10 An experiment is set up to investigate gas exchange in aquatic plants. hydrogencarbonate indicator solution light aquatic plant The hydrogencarbonate indicator solution is orange at the start. Which colour is it after three hours? A blue-black B orange C purple D yellow

1 marks

Answer: C

This question in 0970/21 May/June 2020

11 The diagram shows how the rate of photosynthesis varies with light intensity. The four curves show different conditions of temperature and carbon dioxide concentration. 30°C, 0.2% CO, 20°C, 0.2% CO, rate of photosynthesis 30°C, 0.1% CO, P 20°C, 0.1% CO, light intensity What limits the rate of photosynthesis at point P? light intensity carbon dioxide temperature concentration key J/ = yes X =no

1 marks

Answer: C

This question in 0970/21 May/June 2020

12 Four test-tubes are set up as shown. Which test-tube contains the least carbon dioxide after one hour? A B C D black water polythene to keep aquatic out light animal light light light aquatic plant

1 marks

Answer: C

This question in 0970/21 May/June 2020

11 The diagram shows how the rate of photosynthesis varies with light intensity. The four curves show different conditions of temperature and carbon dioxide concentration. 30°C, 0.2% CO, te ot 20°C, 0.2% CO, rate o photosynthesis 30°C, 0.1% CO, 20°C, 0.1% CO, light intensity What limits the rate of photosynthesis at point P? ar . carbon dioxide light intensity ; temperature concentration A Jv v x key B J x x v=yes Cc x v v X =no D x x v

1 marks

Answer: C

This question in 0970/22 May/June 2020

12 The diagram shows a plant cell. In which part of the cell does photosynthesis occur? A B C D

1 marks

Answer: D

This question in 0970/22 May/June 2020

11 The graph shows how the rate of photosynthesis of a plant changes with light intensity, at three different carbon dioxide concentrations. In each case the temperature is 15 C. 0.10% carbon dioxide X rate of 0.04% carbon dioxide photosynthesis 0.02% carbon dioxide light intensity What is the limiting factor for the rate of photosynthesis at point X on the graph? A carbon dioxide concentration B light intensity C surface area of the plant D temperature

1 marks

Answer: A

This question in 0970/22 Oct/Nov 2020

12 The graph shows how the percentage of protein found in potatoes was affected by the concentration of nitrate fertiliser added to the crop when it was growing. percentage of protein in potatoes concentration of nitrate fertiliser added These results suggest that greater concentrations of nitrate fertiliser allow the potatoes to make more A amino acids. B cellulose. C lipid. D starch.

1 marks

Answer: A

This question in 0970/22 Oct/Nov 2020

13 A plant with striped leaves was kept in bright light for six hours. white stripe green stripe A leaf was taken from the plant and the chlorophyll was removed. The leaf was then tested for starch using iodine solution. Which diagram shows the result of the test? A B C D yellow-brown white blue-black yellow-brown blue-black blue-black green green

1 marks

Answer: A

This question in 0970/21 May/June 2021

14 The graph shows daily carbon dioxide uptake and transpiration by the plant Agave americana. The plant is adapted to live in very dry conditions. 10 0.6 CO2 uptake 8 0.4 transpiration CO2 uptake 6 / g H2O / mg per dm2 per dm2 per hour 4 transpiration 0.2 per hour 2 0 0 0 4 8 12 16 20 24 time of day / hours What can be concluded from this graph? A More stomata are closed during dark periods. B More stomata are closed during light periods. C There is no carbon dioxide uptake during dark periods. D There is no water uptake during light periods.

1 marks

Answer: B

This question in 0970/21 May/June 2021

4 Which part of a cell makes glucose? A cell membrane B chloroplast C nucleus D vacuole

1 marks

Answer: B

This question in 0970/22 May/June 2021

13 A plant with striped leaves was kept in bright light for six hours. white stripe green stripe A leaf was taken from the plant and the chlorophyll was removed. The leaf was then tested for starch using iodine solution. Which diagram shows the result of the test? A B C D yellow-brown white blue-black yellow-brown blue-black blue-black green green

1 marks

Answer: A

This question in 0970/22 May/June 2021

14 The graph shows daily carbon dioxide uptake and transpiration by the plant Agave americana. The plant is adapted to live in very dry conditions. 10 0.6 CO2 uptake 8 0.4 transpiration CO2 uptake 6 / g H2O / mg per dm2 per dm2 per hour 4 transpiration 0.2 per hour 2 0 0 0 4 8 12 16 20 24 time of day / hours What can be concluded from this graph? A More stomata are closed during dark periods. B More stomata are closed during light periods. C There is no carbon dioxide uptake during dark periods. D There is no water uptake during light periods.

1 marks

Answer: B

This question in 0970/22 May/June 2021

18 The diagram shows a plant at different times of year. stage 1 At the start of the growing season, the plant uses the food reserves stored in the bulb for the growth of shoots and leaves. stage 2 Later in the season, the leaves of the plant photosynthesise and the food reserves in the bulb are replaced. new growth of photosynthesising shoots and leaves leaves food reserves in the bulb bulb containing being replaced food reserves stage 1 stage 2 What is the role of the bulb during stage 1 and stage 2? stage 1 stage 2 A sink sink B sink source C source sink D source source

1 marks

Answer: C

This question in 0970/22 May/June 2021

9 In a photosynthesis experiment, a plant is left in bright sunlight for several hours. A leaf is then removed from the plant and tested for starch, using iodine solution. The diagram shows the leaf from the plant that was used in the experiment. white area green area Which diagram shows the result of the experiment? A B C D key iodine solution turns blue-black iodine solution stays brown

1 marks

Answer: C

This question in 0970/22 Oct/Nov 2021

12 Two similar leaves are set up in test-tubes as shown. One is exposed to light, while the other is kept in the dark. green leaf green leaf black paper orange hydrogencarbonate indicator solution After a few hours, which colour would the hydrogencarbonate indicator solution be in each test-tube? light dark A colourless blue-black B purple yellow C red blue D yellow purple

1 marks

Answer: B

This question in 0970/22 Oct/Nov 2021

11 Tomato fruit production was measured in five different environmental conditions. 80 70 60 tomato fruit 50 production 40 / kg per m2 30 20 10 0 1 2 3 4 5 open field unheated heated heated heated glasshouse glasshouse glasshouse glasshouse with carbon with an dioxide gas artificial supplied light source in excess and with carbon dioxide gas supplied in excess environmental conditions What is a correct conclusion for the data shown in the graph? A There are no limiting factors in 1, so tomato fruit production is the lowest. B Temperature is the limiting factor in 3. C Carbon dioxide is the limiting factor in all five environmental conditions. D Light is the limiting factor in 4.

1 marks

Answer: D

This question in 0970/21 May/June 2022

12 How do the air spaces in the spongy mesophyll of a leaf help to adapt it for photosynthesis? A They act as a store of oxygen. B They allow carbon dioxide gas to diffuse through the leaf more rapidly. C They increase the surface area for absorption of light energy. D They let rainwater enter the leaf tissues.

1 marks

Answer: B

This question in 0970/21 May/June 2022

11 The statements describe some of the events that occur in a plant after light energy is absorbed by chlorophyll. 1 converted to chemical energy 2 converted to sucrose for translocation 3 starch is stored in the roots or seeds 4 glucose is produced In which order do these events occur? A 1  4  3  2 B 4  2  3  1 C 4  1  2  3 D 1  4  2  3

1 marks

Answer: D

This question in 0970/22 May/June 2022

12 A deficiency of magnesium ions can cause plant leaves to become yellow between the leaf veins. What is the reason for this? A increased chlorophyll production B increased protein production C decreased chlorophyll production D decreased protein production

1 marks

Answer: C

This question in 0970/22 May/June 2022

35 The diagram shows part of the carbon cycle. carbon dioxide in the atmosphere X X X fossil consumers producers fuels decomposers Which process is shown by the arrows labelled X? A combustion B fossilisation C photosynthesis D respiration

1 marks

Answer: D

This question in 0970/22 May/June 2022

11 Two test-tubes were filled with hydrogencarbonate indicator. An aquatic plant was placed into each test-tube and the test-tubes were sealed with bungs, as shown. hydrogencarbonate box that lamp excludes light indicator aquatic plants test-tube X test-tube Y Test-tube X was illuminated and test-tube Y was kept in the dark. The results are shown. colour of the hydrogencarbonate indicator test-tube at the start of at the end of the investigation the investigation X orange red Y orange yellow What causes the colour changes in the hydrogencarbonate indicator in X and Y? X Y A a decrease in the an increase in the concentration of carbon dioxide concentration of carbon dioxide B a decrease in the an increase in the concentration of oxygen concentration of oxygen C an increase in the a decrease in the concentration of carbon dioxide concentration of carbon dioxide D an increase in the a decrease in the concentration of oxygen concentration of oxygen

1 marks

Answer: A

This question in 0970/22 Oct/Nov 2022

12 The substances listed are found in the leaf of a plant. Which substance is obtained from the soil? A carbon dioxide B chlorophyll C glucose D mineral ions

1 marks

Answer: D

This question in 0970/22 Oct/Nov 2022

35 The diagram shows the flow of energy through living organisms. energy from photosynthesis energy feeding energy in the Sun in plants animals Which term should be placed in both boxes to complete the diagram? A chemical B heat C kinetic D light

1 marks

Answer: A

This question in 0970/22 Oct/Nov 2022

39 Deforestation results in an increase in the concentration of carbon dioxide in the atmosphere. What is the correct explanation? A There is less decay. B There is less photosynthesis. C There is less respiration. D There is less transpiration.

1 marks

Answer: B

This question in 0970/22 Oct/Nov 2022

11 An experiment is set up to investigate gas exchange in aquatic plants. hydrogencarbonate indicator solution light aquatic plant The hydrogencarbonate indicator solution is orange at the start. Which colour is it after three hours? A blue-black B orange C purple D yellow

1 marks

Answer: C

This question in 0970/21 May/June 2023

12 Certain factors are needed for photosynthesis. If a factor is in short supply, it limits the rate of photosynthesis. Which of these could be limiting factors? 1 carbon dioxide 2 oxygen 3 light intensity A 1 and 2 B 1 and 3 C 2 and 3 D 3 only

1 marks

Answer: B

This question in 0970/21 May/June 2023

16 Sucrose and amino acids move around a plant from sources to sinks. Which row shows the sources and sinks? palisade root cortex cells xylem vessels mesophyll cells A source and sink neither source B sink sink source and sink C neither source and sink sink D source and sink source neither

1 marks

Answer: A

This question in 0970/21 May/June 2023

11 The diagram shows a leaf on a plant used in a photosynthesis experiment. At the start of the experiment, there is no starch in the leaf. A piece of black paper is attached to the upper surface of the leaf. The plant is placed in bright light for 12 hours. Four discs are then cut from the leaf in the positions shown on the diagram. The discs are tested for starch. Which disc contains starch? disc A disc B green area white area disc C disc D black paper

1 marks

Answer: A

This question in 0970/22 May/June 2023

12 The graph shows the effect of temperature on the rate of photosynthesis. rate of photosynthesis 0 5 10 15 20 25 30 35 40 temperature / °C Which statement explains the change in rate of photosynthesis between 15 °C and 20 °C? A Chlorophyll is able to transfer more energy in chemicals to energy in light. B Enzymes involved in photosynthesis have denatured. C Kinetic energy of molecules is increasing, resulting in more effective collisions. D Light intensity and not temperature is limiting the rate of photosynthesis.

1 marks

Answer: C

This question in 0970/22 May/June 2023

35 Which term is used to describe an organism that makes its own organic nutrients? A carnivore B decomposer C herbivore D producer

1 marks

Answer: D

This question in 0970/22 May/June 2023

11 The diagram shows how the rate of photosynthesis varies with light intensity. The four curves show different conditions of temperature and carbon dioxide concentration. 30°C, 0.2% CO, te ot 20°C, 0.2% CO, rate o photosynthesis 30°C, 0.1% CO, 20°C, 0.1% CO, light intensity What limits the rate of photosynthesis at point P? ar ; carbon dioxide light intensity ; temperature concentration A Jv v x key B J x x v=yes Cc x v v X =no D x x v

1 marks

Answer: C

This question in 0970/22 Oct/Nov 2023

12 The diagram shows a cell with groups of bacteria around its edge. cell cytoplasm spiral-shaped chloroplast bacteria The bacteria have moved to areas of high oxygen concentration. Which process in the cell causes the bacteria to form these groups? A digestion B photosynthesis C reproduction D respiration

1 marks

Answer: B

This question in 0970/22 Oct/Nov 2023

10 The diagram shows an experiment to investigate the effect of increasing light intensity on the rate of photosynthesis in an aquatic plant. The rate is found by measuring the rate of bubble release by the plant. As the light intensity increases, the rate of bubble release increases and then becomes constant. bubble light Which statement describes why the rate of bubble release becomes constant at high light intensities? A Carbon dioxide concentration becomes a limiting factor. B Light intensity becomes a limiting factor. C Oxygen availability becomes a limiting factor. D Water availability becomes a limiting factor.

1 marks

Answer: A

This question in 0970/21 May/June 2024

11 The diagram shows a section through the leaf of a flowering plant. 1 2 3 4 Where does photosynthesis take place? A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

1 marks

Answer: B

This question in 0970/21 May/June 2024

18 Which statement is correct for a flowering plant during photosynthesis? A The flowers, fruits, leaves and roots are all sources of sucrose. B The fruits are a source of sucrose and the flowers are a sink. C The leaves are a source of sucrose and the fruits are a sink. D The roots are a source of sucrose and the leaves are a sink.

1 marks

Answer: C

This question in 0970/21 May/June 2024

11 Which substance is needed to make chlorophyll and which part of the plant absorbs the substance? part of the plant substance where the substance is absorbed A calcium root hairs B calcium stomata C magnesium root hairs D magnesium stomata

1 marks

Answer: C

This question in 0970/22 Oct/Nov 2024

1 Which characteristic of living things requires carbon dioxide to diffuse into a leaf? A excretion B movement C nutrition D respiration

1 marks

Answer: C

This question in 0970/21 May/June 2025

8 Which descriptions of adaptations for photosynthesis are correct for spongy mesophyll tissue? air spaces for long, rectangular efficient gas cells to absorb exchange light A yes yes B yes no C no yes D no no

1 marks

Answer: B

This question in 0970/21 May/June 2025

9 A student investigated how the rate of photosynthesis is affected by carbon dioxide concentration, temperature and light intensity. The graphs show the results. 2 rate of rate of photosynthesis photosynthesis 3 1 carbon dioxide temperature concentration 4 rate of photosynthesis light intensity What is a correct statement for these results? A Carbon dioxide concentration is a limiting factor at 1. B No enzymes are denatured at 3. C Light intensity is a limiting factor at 4. D Temperature is a limiting factor at 2.

1 marks

Answer: A

This question in 0970/22 May/June 2025

35 Which row describes the energy flow into and through a food chain that starts with a plant? energy transferred energy entering between organisms a food chain in a food chain A chemical chemical B chemical heat C light chemical D light heat

1 marks

Answer: C

This question in 0970/22 May/June 2025