Cambridge IGCSE Science - Combined 0653 — 2021 May/June Paper 1 · Variant 2
0653/12/M/J/21 · 40 questions · 40 marks · ≈45 min
The question paper and its mark scheme, free to read here and free to download. This is Cambridge’s own paper, exactly as it was sat.
Question paper16 pages
Mark scheme3 pages
Answers below. Sit the paper first if you are practising.
Questions as text
Q1 · The diagram shows a plant cell as seen under a light microscope
1 The diagram shows a plant cell as seen under a light microscope. X What is the function of the part labelled X? A photosynthesis B site of chemical reactions C stores DNA D supports the cell
Mark scheme: D
Q2 · The diagrams represent four similar animal cells immersed in blood plasma
2 The diagrams represent four similar animal cells immersed in blood plasma. The black dots represent molecules of dissolved oxygen. Which cell will have oxygen molecules diffusing into it most rapidly? A B C D
Mark scheme: C
Q3 · A student tests an unknown substance with biuret reagent
3 A student tests an unknown substance with biuret reagent. It produces a violet colour. What is the unknown substance an example of? A fat B protein C reducing sugar D starch
Mark scheme: B
Q4 · Which name is given to biological catalysts?
4 Which name is given to biological catalysts? A antibodies B enzymes C hormones D platelets
Mark scheme: B
Q5 · The flow diagram shows the stages in testing a green leaf for starch
5 The flow diagram shows the stages in testing a green leaf for starch. 1, 2, 3 and 4 are all liquids. 4 iodine solution white tile hot water 1 2 3 boiling water boiling alcohol to warm water to kill the leaf remove the chlorophyll to wash the leaf What are the colours of liquids 2 and 4 for a leaf that contains starch? 2 4 A green blue / black B colourless brown C colourless blue / black D green brown
Mark scheme: A
Q6 · Which part of the alimentary canal carries out digestion and absorption?
6 Which part of the alimentary canal carries out digestion and absorption? A C B D
Mark scheme: B
Q7 · Which statement describes chemical digestion?
7 Which statement describes chemical digestion? A food particles passing along the alimentary canal B large food molecules being broken down into smaller molecules C large pieces of food being broken down into smaller pieces D nutrients passing through the wall of the small intestine
Mark scheme: B
Q8 · What can be used to test for the presence of carbon dioxide?
8 What can be used to test for the presence of carbon dioxide? A Benedict’s solution B ethanol C iodine solution D limewater
Mark scheme: D
Q9 · Which equation represents aerobic respiration?
9 Which equation represents aerobic respiration? A carbon dioxide + glucose oxygen + water B carbon dioxide + water glucose + oxygen C glucose + oxygen carbon dioxide + water D glucose + water carbon dioxide + oxygen
Mark scheme: C
Q10 · When the hormone adrenaline is released in humans it causes changes in breathing rate and…
10 When the hormone adrenaline is released in humans it causes changes in breathing rate and pupil size. What are the correct changes? breathing rate pupil size A decreases decreases B decreases increases C increases decreases D increases increases
Mark scheme: D
Q11 · The diagram shows the human female reproductive system
11 The diagram shows the human female reproductive system. Where does fertilisation usually take place? D C A B
Mark scheme: D
Q12 · The diagram shows a food web
12 The diagram shows a food web. hawk snake small bird lizard snail grasshopper grass Which statement about the snake is correct? A It is a consumer and it is a carnivore. B It is a producer and it is a carnivore. C It is a consumer and it is a herbivore. D It is a producer and it is a herbivore.
Mark scheme: A
Q13 · Which process takes carbon dioxide out of the air?
13 Which process takes carbon dioxide out of the air? A combustion B decomposition C photosynthesis D plant respiration
Mark scheme: C
Q14 · What is an example of a physical change?
14 What is an example of a physical change? A carbon dioxide turning limewater milky B the crystallisation of copper(II) sulfate from solution C the electrolysis of molten lead(II) bromide D the thermal decomposition of calcium carbonate
Mark scheme: B
Q15 · Which substances are mixtures?
15 Which substances are mixtures? 1 air 2 brass 3 sodium chloride A 1 and 2 only B 1 and 3 only C 2 and 3 only D 1, 2 and 3
Mark scheme: A
Q16 · Which statement about the particles is correct?
16 Which statement about the particles is correct? A 1 1H has the same number of protons as neutrons. B 2 H + has the same number of electrons as neutrons. 1 C OH– contains more protons than electrons. D NH3 has the same number of protons as electrons.
Mark scheme: D
Q17 · The apparatus used in an electrolysis experiment is shown
17 The apparatus used in an electrolysis experiment is shown. – + Q R S Which row identifies Q, R and S? Q R S A anode cathode electrode B cathode anode electrode C anode cathode electrolyte D cathode anode electrolyte
Mark scheme: D
Q18 · Some calcium carbonate and dilute hydrochloric acid start to react
18 Some calcium carbonate and dilute hydrochloric acid start to react. Water is then added to the reaction mixture. What happens to the rate of the reaction? A It decreases. B It increases. C It stays the same. D It stops.
Mark scheme: A
Q19 · The diagram shows an experiment to prepare a salt from compounds P and Q
19 The diagram shows an experiment to prepare a salt from compounds P and Q. aqueous P stirrer aqueous Q + Universal Indicator Aqueous Q has a pH value of 1. Aqueous P is added until the pH value of the mixture reaches 7. What are the formulae of compounds P and Q? compound P compound Q A HCl NaOH B HNO3 H2SO4 C KOH HCl D NaOH NH3
Mark scheme: C
More questions on The characteristic properties of acids and bases
Q20 · Which two substances form a white precipitate when they are mixed?
20 Which two substances form a white precipitate when they are mixed? A barium chloride and hydrochloric acid B barium chloride and nitric acid C silver nitrate and hydrochloric acid D silver nitrate and nitric acid
Mark scheme: C
Q21 · Which statement describes how the elements change across a period in the Periodic Table…
21 Which statement describes how the elements change across a period in the Periodic Table from left to right? A They change from elements to compounds. B They change from metals to non-metals. C They change from gases to solids. D They change from non-metals to metals.
Mark scheme: B
Q22 · Which row shows the properties of a transition element?
22 Which row shows the properties of a transition element? melting electrical colour of catalytic point conductivity chloride properties A high high white no B high low white no C high high green yes D low low blue yes
Mark scheme: C
Q23 · Which words describe a noble gas?
23 Which words describe a noble gas? A compound, colourless, does not burn in air B element, colourless, burns in air C element, colourless, does not burn in air D element, green, does not burn in air
Mark scheme: C
Q24 · Which compound can oxidise carbon?
24 Which compound can oxidise carbon? A aluminium oxide B copper oxide C magnesium oxide D potassium oxide
Mark scheme: B
Q25 · An experiment is set up to show the effect of air and water on iron
25 An experiment is set up to show the effect of air and water on iron. tube X tube Y iron wire iron wire coated with grease air air water water The experiment is left for one week. What happens to the water level in each tube? tube X tube Y A falls falls B no change rises C rises rises D rises no change
Mark scheme: D
Q26 · Which type of compound contains only carbon and hydrogen?
26 Which type of compound contains only carbon and hydrogen? A carbohydrate B carbonate C hydrocarbon D hydroxide
Mark scheme: C
Q27 · Which process produces alkenes?
27 Which process produces alkenes? A cracking B fractional distillation C polymerisation D reduction
Mark scheme: A
Q28 · Which speed–time graph represents the motion of an object with constant, non-zero…
28 Which speed–time graph represents the motion of an object with constant, non-zero acceleration? A B speed speed 0 0 0 time 0 time C D speed speed 0 0 0 time 0 time
Mark scheme: C
Q29 · The gravitational field strength g on the surface of the Earth is 10 N / kg
29 The gravitational field strength g on the surface of the Earth is 10 N / kg. What is the weight of a 500 g mass on the surface of the Earth? A 5.0 kg B 5.0 N C 5000 kg D 5000 N
Mark scheme: B
Q30 · Which row shows apparatus used to measure length, time and volume?
30 Which row shows apparatus used to measure length, time and volume? length time volume A measuring cylinder metre rule stop-clock B measuring cylinder stop-clock metre rule C metre rule measuring cylinder stop-clock D metre rule stop-clock measuring cylinder
Mark scheme: D
More questions on Physical quantities and measurement techniques
Q31 · A block is placed on the ground causing a pressure on the ground
31 A block is placed on the ground causing a pressure on the ground. Which row shows a pair of changes that must increase the pressure on the ground? area of contact weight of block with ground A decreases decreases B decreases increases C increases decreases D increases increases
Mark scheme: C
Q32 · A student applies a force to an object, causing the object to move in the same direction…
32 A student applies a force to an object, causing the object to move in the same direction as the force. She measures the size of the force and the distance moved by the object. Which quantity can she now calculate? A the acceleration of the object B the power she produces C the speed of the object D the work done on the object
Mark scheme: D
Q33 · Cold water evaporates as molecules leave it
33 Cold water evaporates as molecules leave it. Which molecules leave the water and from which part of the water do they leave? molecules that where they leave the water leave from A least energetic the surface only B least energetic throughout the water C most energetic the surface only D most energetic throughout the water
Mark scheme: C
Q34 · Which material is a good conductor of heat?
34 Which material is a good conductor of heat? A copper B glass C plastic D wood
Mark scheme: A
Q35 · A navigation buoy floating on the sea oscillates up and down as a wave passes
35 A navigation buoy floating on the sea oscillates up and down as a wave passes. navigation buoy sea In 2.0 minutes, 6.0 wavelengths pass the buoy. What is the frequency of the waves? A 0.050 Hz B 0.33 Hz C 3.0 Hz D 20 Hz
Mark scheme: A
Q36 · The diagram shows rays of light from an object being reflected by a plane mirror
36 The diagram shows rays of light from an object being reflected by a plane mirror. plane mirror X object Y At which labelled point is the image formed, and is the image real or virtual? image real or virtual A at X real B at X virtual C at Y real D at Y virtual
Mark scheme: D
Q37 · The diagram represents a circuit that includes a battery, an ammeter, a voltmeter and a…
37 The diagram represents a circuit that includes a battery, an ammeter, a voltmeter and a variable resistor. A V What happens to the readings on the meters as the resistance of the variable resistor is increased? ammeter reading voltmeter reading A decreases decreases B decreases stays constant C increases decreases D increases stays constant
Mark scheme: B
Q38 · Two lamps are connected in the circuit shown
38 Two lamps are connected in the circuit shown. The currents at three points are labelled I1, I2 and I3. I1 I2 I3 How are I1, I2 and I3 related? Use the key to help you. key < less than > greater than = equal to A I1 < I2 < I3 B I1 = I2 = I3 C I1 > I2 and I1 = I3 D I1 > I2 > I3
Mark scheme: B
Q39 · Two resistors are connected as shown
39 Two resistors are connected as shown. 3.0 Ω 3.0 Ω What is the combined resistance of the two resistors? A less than 3.0 B 3.0 C 6.0 D 9.0
Mark scheme: A
Q40 · An air conditioner and a television are both connected to the same electrical circuit
40 An air conditioner and a television are both connected to the same electrical circuit. X power air television supply conditioner The current in the air conditioner is 9.0 A and the current in the television is 2.0 A. Several different fuses are available. Which fuse should be connected at X? A 1 A B 3 A C 7 A D 13 A
Mark scheme: D
What was in this paper
The subtopics covered by these 40 questions, and how many questions each got. Open one in a new tab to see every Cambridge question on it.
3Identification of ions and gases2Alkenes1Arrangement of elements1Atomic structure and the Periodic Table1Biological molecules1Carbon cycle1Cell structure1Corrosion of metals1Diffusion1Digestion1Digestive system1Drugs1Electrical safety1Electrolysis1Elements, compounds and mixtures1Energy, work and power1Enzymes1Food chains and food webs1General properties of waves1Kinetic particle model of matter1Light1Mass and weight1Motion1Noble gases1Photosynthesis1Physical and chemical changes1Physical quantities and measurement techniques1Pressure1Rate of reaction1Redox1Respiration1Sexual reproduction in humans1Terminology1The characteristic properties of acids and bases1Transfer of thermal energy1Transition elements1What you needed in this session
Cambridge’s own grade thresholds for 2021 May/June, Paper 1 · Variant 2. A higher threshold means an easier paper — the bar moves with how the cohort did.