Photosynthesis — Paper 2 · IGCSE Science - Combined 0653

1 The diagram shows a palisade cell as seen under a light microscope. Which structure converts light energy to chemical energy? B A C D

1 marks

Answer: B

This question in 0653/22 Feb/March 2017

4 What is the equation for photosynthesis? A 6H2O + 6CO2 → C6H12O6 + 6O2 B 6H2O + 6O2 → C6H12O6 + 6CO2 C C6H12O6 + 6CO2 → 6O2 + 6H2O D C6H12O6 + 6O2 → 6CO2 + 6H2O

1 marks

Answer: A

This question in 0653/22 Feb/March 2017

4 Which substance in leaves traps light energy for use in photosynthesis? A carbohydrate B carbon C carbon dioxide D chlorophyll

1 marks

Answer: D

This question in 0653/21 May/June 2017

4 The equation summarises a process that occurs in living organisms. 6H2O + 6CO2 → C6H12O6 + 6O2 Which molecule contains the greatest amount of chemical energy? A H2O B CO2 C C6H12O6 D O2

1 marks

Answer: C

This question in 0653/23 May/June 2017

2 The diagram shows a palisade cell. Which structure converts energy from light into chemical energy? D C A B

1 marks

Answer: D

This question in 0653/21 Oct/Nov 2017

5 Which letters from the list represent the balanced equation for photosynthesis? P C6H12O6 T H2O Q 6C6H12O6 U 6H2O R CO2 V O2 S 6CO2 W 6O2 A P + U → R + V B Q + T → S + U C R + T → W + P D U + S → P + W

1 marks

Answer: D

This question in 0653/21 Oct/Nov 2017

2 The diagram shows a palisade cell. Which structure converts energy from light into chemical energy? D C A B

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2017

2 The diagram shows a palisade cell. Which structure converts energy from light into chemical energy? D C A B

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2017

4 The list shows chemicals that are important to a plant. 1 carbon dioxide 2 nitrates 3 oxygen 4 water Which chemicals does a plant use in photosynthesis? A 1, 2 and 4 B 1 and 2 only C 1 and 4 only D 3 and 4 only

1 marks

Answer: C

This question in 0653/23 Oct/Nov 2017

5 A student is investigating how light affects photosynthesis. gas measuring cylinder beaker glass funnel water aquatic plant X Y The student shines a light from point Y and measures the volume of gas produced in five minutes. Which gas is produced and how does the rate of gas production change when the light is moved from Y to X? rate of gas gas produced production A carbon dioxide decreases B carbon dioxide increases C oxygen decreases D oxygen increases

1 marks

Answer: D

This question in 0653/22 Feb/March 2018

10 Light shines on a shoot tip from the direction shown. light X Y After three days the shoot tip has bent towards the light. What is the reason for this change? A Auxin moves away from the light causing cell elongation in area Y. B Auxin moves away from the light preventing cell elongation in area Y. C Auxin moves towards the light causing cell elongation in area X. D Auxin moves towards the light preventing cell elongation in area X.

1 marks

Answer: A

This question in 0653/22 Feb/March 2018

4 Which two chemical substances are required for photosynthesis? A carbon dioxide and glucose B glucose and oxygen C oxygen and water D water and carbon dioxide

1 marks

Answer: D

This question in 0653/21 May/June 2018

3 Which two chemical substances are required for photosynthesis? A carbon dioxide and glucose B glucose and oxygen C oxygen and water D water and carbon dioxide

1 marks

Answer: D

This question in 0653/22 May/June 2018

1 Which structure found in plant cells traps light energy for photosynthesis? A cell wall B chloroplast C nucleus D vacuole

1 marks

Answer: B

This question in 0653/23 May/June 2018

4 Which two chemical substances are required for photosynthesis? A carbon dioxide and glucose B glucose and oxygen C oxygen and water D water and carbon dioxide

1 marks

Answer: D

This question in 0653/23 May/June 2018

5 The diagram shows a leaf that was tested for starch using iodine solution. green area white area Which row shows the results for this leaf and explains the results? green area of white area of explanation leaf after test leaf after test A blue-black blue-black chlorophyll is found in all parts of the leaf B blue-black brown chlorophyll is found in only part of the leaf C brown brown chlorophyll is found in all parts of the leaf D brown blue-black chlorophyll is found in only part of the leaf

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2018

5 The diagram shows a leaf that was tested for starch using iodine solution. green area white area Which row shows the results for this leaf and explains the results? green area of white area of explanation leaf after test leaf after test A blue-black blue-black chlorophyll is found in all parts of the leaf B blue-black brown chlorophyll is found in only part of the leaf C brown brown chlorophyll is found in all parts of the leaf D brown blue-black chlorophyll is found in only part of the leaf

1 marks

Answer: B

This question in 0653/22 Oct/Nov 2018

4 The diagram shows a leaf that was tested for starch using iodine solution. green area white area Which row shows the results for this leaf and explains the results? green area of white area of explanation leaf after test leaf after test A blue-black blue-black chlorophyll is found in all parts of the leaf B blue-black brown chlorophyll is found in only part of the leaf C brown brown chlorophyll is found in all parts of the leaf D brown blue-black chlorophyll is found in only part of the leaf

1 marks

Answer: B

This question in 0653/23 Oct/Nov 2018

1 The following are features of palisade mesophyll cells: 1 column shaped 2 have a nucleus 3 have large vacuoles 4 have many chloroplasts Which features of these cells help them to absorb maximum light and carry out photosynthesis? A 1, 2, 3 and 4 B 1 and 4 only C 2 and 4 only D 4 only

1 marks

Answer: B

This question in 0653/22 Feb/March 2019

3 Which graph shows the effect of light intensity on the rate of photosynthesis? A B rate of rate of photosynthesis photosynthesis 0 0 0 light intensity 0 light intensity C D rate of rate of photosynthesis photosynthesis 0 0 0 light intensity 0 light intensity

1 marks

Answer: B

This question in 0653/22 Feb/March 2019

12 A farmer chops down a tree to provide firewood. He gets warm when chopping down the tree. The farmer then burns the wood to keep warm. What is the original source of the energy that warms the farmer in both cases? A photosynthesis by the tree growing the wood B respiration C the match used to light the fire D the Sun

1 marks

Answer: D

This question in 0653/22 Feb/March 2019

2 An incomplete symbol equation for photosynthesis is given below. xCOy + xH2O → CxHzOx + xOy Which row shows the numbers that should replace x, y and z to make the equation balanced? x y z A 6 2 6 B 6 12 2 C 6 2 12 D 12 6 2

1 marks

Answer: C

This question in 0653/22 May/June 2019

7 Which substances are used and produced during photosynthesis? substances used substances produced A carbon dioxide and glucose oxygen and water B carbon dioxide and water glucose and oxygen C glucose and oxygen carbon dioxide and water D oxygen and water carbon dioxide and glucose

1 marks

Answer: A

This question in 0653/23 May/June 2019

9 Diagram 1 shows a germinating bean seed placed horizontally. pin diagram 1 Diagram 2 shows the same seed after three days. The shoot has grown upwards because of the action of an auxin. Where is the auxin produced? D C A B pin diagram 2

1 marks

Answer: D

This question in 0653/23 May/June 2019

9 Auxins are produced in the tip of a shoot. In an experiment, auxin was applied to a plant shoot just below its tip. Which row describes the change to the shoot and explains this change? shoot explanation A becomes longer cells divide B becomes longer cells elongate C becomes longer cells elongate and then divide D did not change length the auxin has no effect

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2019

3 What is the word equation for photosynthesis? A carbon dioxide + oxygen → glucose + water B carbon dioxide + water → glucose + oxygen C glucose + oxygen → carbon dioxide + water D glucose + water → carbon dioxide + oxygen

1 marks

Answer: B

This question in 0653/23 Oct/Nov 2019

8 Which substances are the products of photosynthesis? A carbon dioxide and glucose B glucose and oxygen C oxygen and water D water and carbon dioxide

1 marks

Answer: B

This question in 0653/22 May/June 2020

4 What is necessary for photosynthesis? 1 carbon dioxide 2 chlorophyll 3 glucose 4 light 5 oxygen 6 water A 1, 2, 4 and 6 B 1, 3, 4 and 6 C 2, 3, 4 and 5 D 3, 4, 5 and 6

1 marks

Answer: A

This question in 0653/21 Oct/Nov 2020

4 What is the balanced equation for photosynthesis? A CO2 + H2O  C6H12O6 + O2 B CO2 + 6H2O  6C6H12O6 + O2 C 6CO2 + 6H2O  C6H12O6 + 6O2 D 6CO2 + 12H2O  6C6H12O6 + 6O2

1 marks

Answer: C

This question in 0653/21 May/June 2021

4 Which row is correct for photosynthesis? cells where substrates products photosynthesis occurs A C6H12O6 + 6O2 6H2O + 6CO2 palisade mesophyll B C6H12O6 + 6O2 6H2O + 6CO2 upper epidermis C 6H2O + 6CO2 C6H12O6 + 6O2 palisade mesophyll D 6H2O + 6CO2 C6H12O6 + 6O2 upper epidermis

1 marks

Answer: C

This question in 0653/22 May/June 2021

10 A shoot tip receives light from one direction only, as shown. Which diagram shows how auxin will distribute and how the shoot will respond? A B C D auxin

1 marks

Answer: A

This question in 0653/22 May/June 2021

4 The leaves of plants produce carbohydrates during photosynthesis. How are these carbohydrates used by the plants? for respiration to make other for storage substances A Jv x x B x x Jv Cc v x JV D J Jv Jv

1 marks

Answer: D

This question in 0653/23 May/June 2021

13 Which process takes carbon dioxide out of the air? A combustion B decomposition C photosynthesis D plant respiration

1 marks

Answer: C

This question in 0653/23 May/June 2021

4 Which letters from the list represent the balanced equation for photosynthesis? P C6H12O6 T H2O Q 6C6H12O6 U 6H2O R CO2 V O2 S 6CO2 W 6O2 A P + U  R + V B Q + T  S + U C R + T  W + P D U + S  P + W

1 marks

Answer: D

This question in 0653/21 Oct/Nov 2021

5 Which letters from the list represent the balanced equation for photosynthesis? P C6H12O6 T H2O Q 6C6H12O6 U 6H2O R CO2 V O2 S 6CO2 W 6O2 A P + U  R + V B Q + T  S + U C R + T  W + P D U + S  P + W

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2021

5 Which letters from the list represent the balanced equation for photosynthesis? P C6H12O6 T H2O Q 6C6H12O6 U 6H2O R CO2 V O2 S 6CO2 W 6O2 A P + U  R + V B Q + T  S + U C R + T  W + P D U + S  P + W

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2021

9 The shoot of a plant grows towards the light. plant shoot light Which diagram shows the correct distribution of auxin in this shoot? A B C D key = auxin

1 marks

Answer: D

This question in 0653/22 Feb/March 2022

4 Which graph correctly shows the effect of varying light intensity on the rate of photosynthesis? A B rate of rate of photosynthesis photosynthesis 0 0 0 light intensity 0 light intensity C D rate of rate of photosynthesis photosynthesis 0 0 0 light intensity 0 light intensity

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2022

4 Which substance in leaves traps light energy for use in photosynthesis? A carbohydrate B carbon C carbon dioxide D chlorophyll

1 marks

Answer: D

This question in 0653/22 Oct/Nov 2022

5 Four test-tubes are set up as shown. In which test-tube is there an increase in oxygen concentration after 4 hours? A B C D black polythene to keep water out light light light light light water plant water snail

1 marks

Answer: D

This question in 0653/21 May/June 2023

4 In plants, photosynthesis takes place in the leaf. During photosynthesis, … P … transfers … Q … energy into … R … energy. This is used for the synthesis of … S … . Which row correctly completes gaps P, Q, R and S? P Q R S A chlorophyll chemical light carbohydrate B chlorophyll light chemical carbohydrate C glucose chemical light chlorophyll D glucose light chemical chlorophyll

1 marks

Answer: B

This question in 0653/22 May/June 2023

4 In plants, which energy transfer occurs in chlorophyll during photosynthesis? A chemical to light B heat to chemical C light to chemical D chemical to heat

1 marks

Answer: C

This question in 0653/23 May/June 2023

1 The diagram shows a plant absorbing carbon dioxide in order to carry out photosynthesis. carbon dioxide Which characteristic of all living organisms is this? A movement B nutrition C excretion D reproduction

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2023

9 The diagram shows the apparatus used in an investigation on gas exchange in organisms. In which test-tube would the concentration of oxygen decrease most rapidly? A B C D light light snail water plant light-proof black box

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2023

9 Which statements correctly describe tropic responses? 1 Gravitropism is the growth of a shoot toward the light. 2 Gravitropism is the growth of a root downwards. 3 Phototropism is the growth of a shoot toward the light. 4 Phototropism is the growth of a root downwards. A 1 and 2 B 1 and 4 C 2 and 3 D 3 and 4

1 marks

Answer: C

This question in 0653/22 Feb/March 2024

4 Which row is correct for photosynthesis in a leaf? cells where substrates products photosynthesis occurs A C6H12O6 + 6O2 6H2O + 6CO2 palisade mesophyll B C6H12O6 + 6O2 6H2O + 6CO2 upper epidermis C 6H2O + 6CO2 C6H12O6 + 6O2 palisade mesophyll D 6H2O + 6CO2 C6H12O6 + 6O2 upper epidermis

1 marks

Answer: C

This question in 0653/22 May/June 2024

10 The table shows some possible tropic responses in a plant. direction of growth response to part of plant light (from gravity one direction) 1 root away towards 2 root towards away 3 shoot away towards 4 shoot towards away What are the correct tropic responses for gravitropism and phototropism? A 1 and 3 B 1 and 4 C 2 and 3 D 2 and 4

1 marks

Answer: C

This question in 0653/22 May/June 2024

5 Which substances are used and produced during photosynthesis? substances used substances produced A carbon dioxide and glucose oxygen and water B carbon dioxide and water glucose and oxygen C glucose and oxygen carbon dioxide and water D oxygen and water carbon dioxide and glucose

1 marks

Answer: B

This question in 0653/23 May/June 2024

10 A light shines onto a shoot from one side. Which row explains why the shoot bends towards the light? more auxin on the more cell elongation side of the shoot on the side of the shoot A furthest from the light furthest from the light B furthest from the light nearest to the light C nearest to the light furthest from the light D nearest to the light nearest to the light

1 marks

Answer: A

This question in 0653/23 May/June 2024

9 Which row is correct for auxin in a shoot? side of shoot where effect of auxin more auxin is found A cell division closer to the light B cell division further away from the light C cell elongation closer to the light D cell elongation further away from the light

1 marks

Answer: D

This question in 0653/23 Oct/Nov 2024

5 Carbon dioxide is needed for photosynthesis. How many molecules of carbon dioxide are needed to make five molecules of glucose? A 6 B 12 C 30 D 36

1 marks

Answer: C

This question in 0653/22 Feb/March 2025

4 What is the balanced equation for photosynthesis? A CO2 + H2O  C6H12O6 + O2 B CO2 + 6H2O  6C6H12O6 + O2 C 6CO2 + 6H2O  C6H12O6 + 6O2 D 6CO2 + 12H2O  6C6H12O6 + 6O2

1 marks

Answer: C

This question in 0653/21 May/June 2025

5 The diagram shows a transverse section through a leaf. layer 1 layer 2 layer 3 layer 4 Which layers have cells that can produce oxygen in the presence of light? A 1, 2, 3 and 4 B 1, 2 and 3 only C 2 and 3 only D 3 and 4 only

1 marks

Answer: D

This question in 0653/21 May/June 2025

6 Four tubes that contain red hydrogencarbonate indicator are set up as shown. After five hours, the colour of the hydrogencarbonate indicator is recorded. aquatic plant hydrogencarbonate indicator in light in light in dark in dark 1 2 3 4 Which row shows the colour of the hydrogencarbonate indicator in each tube after five hours? 1 2 3 4 A purple red red red B purple red yellow red C red yellow red purple D yellow red purple red

1 marks

Answer: B

This question in 0653/22 May/June 2025

2 Palisade mesophyll cells are specialised cells. What is the function of these specialised cells? A photosynthesis B transport C reproduction D immunity

1 marks

Answer: A

This question in 0653/23 May/June 2025

6 An aquatic plant is in a test-tube of water. The test-tube is sealed and placed in the dark. water aquatic plant Which changes occur to the concentration of carbon dioxide and oxygen in the water after two hours? concentration of concentration of carbon dioxide oxygen A decreases decreases B decreases increases C increases decreases D increases increases

1 marks

Answer: C

This question in 0653/23 May/June 2025

5 Which graph shows the effect of light intensity on the rate of photosynthesis? A B rate of rate of photosynthesis photosynthesis 0 0 0 0 light intensity light intensity C D rate of rate of photosynthesis photosynthesis 0 0 0 0 light intensity light intensity

1 marks

Answer: B

This question in 0653/21 Oct/Nov 2025

5 Which statement about photosynthesis is correct? A Chlorophyll transfers energy from light into energy in chemicals for the synthesis of carbohydrates. B Chlorophyll transfers energy from light into energy in chemicals for the synthesis of carbon dioxide. C Mitochondria transfer energy from light into energy in chemicals for the synthesis of carbohydrates. D Mitochondria transfer energy from light into energy in chemicals for the synthesis of carbon dioxide.

1 marks

Answer: A

This question in 0653/22 Oct/Nov 2025

4 The graph shows the effect of temperature and carbon dioxide concentration on the rate of photosynthesis in a plant. key 0.20% carbon dioxide rate of in atmosphere photosynthesis 0.04% carbon dioxide in atmosphere 10 15 20 25 30 35 40 45 temperature / °C What is a correct conclusion from the graph? A The higher the temperature, the faster the rate of photosynthesis. B The optimum temperature for photosynthesis for both carbon dioxide concentrations is 37.5 °C. C The rate of photosynthesis depends on both carbon dioxide concentration and temperature. D Increasing carbon dioxide concentration doubles the rate of photosynthesis at all temperatures.

1 marks

Answer: C

This question in 0653/23 Oct/Nov 2025