Question 1 (Subtopic Code: B1.1)
What is correct for all living organisms?
A. They are sensitive to changes in their environment.
B. They excrete solid waste from their bodies.
C. They feed on other living organisms.
D. They grow larger by increasing their cell number.
▶️Answer/Explanation
Answer: A
Explanation: All living organisms are sensitive to changes in their environment, which is one of the key characteristics of life. This sensitivity allows them to respond to stimuli, which is essential for survival.
Question 2 (Subtopic Code: B2.1)
The diagram shows a body cell and a blood capillary. The arrow represents the direction of diffusion.
For aerobic respiration to occur in the cell, which substances does the arrow represent?
A. carbon dioxide and glucose
B. carbon dioxide and water
C. oxygen and glucose
D. oxygen and water
▶️Answer/Explanation
Answer: C
Explanation: For aerobic respiration to occur, the cell requires oxygen and glucose. Oxygen is needed for the breakdown of glucose to release energy, and glucose is the primary fuel for cellular respiration.
Question 3 (Subtopic Code: B4.1)
Which chemical element is found in proteins, but not in carbohydrates or fats?
A. carbon
B. hydrogen
C. oxygen
D. nitrogen
▶️Answer/Explanation
Answer: D
Explanation: Nitrogen is a key element found in proteins (in the form of amino acids) but is not present in carbohydrates or fats. Proteins contain nitrogen due to the presence of amino groups in their structure.
Question 4 (Subtopic Code: B5.1)
The graphs show the possible effects of temperature on the rate of reaction of an enzyme. Which graph is correct for a human enzyme?
▶️Answer/Explanation
Answer: A
Explanation: Human enzymes typically have an optimal temperature around 37°C. The rate of reaction increases with temperature up to this point, after which the enzyme denatures, and the rate drops sharply. Graph A correctly represents this behavior.
Question 5 (Subtopic Code: B6.1)
Plants make sugars from water and carbon dioxide. From where do they get the carbon dioxide?
A. rain soaking into the leaves
B. the air
C. the soil through the roots
D. they make it in photosynthesis
▶️Answer/Explanation
Answer: B
Explanation: Plants obtain carbon dioxide from the air through tiny pores called stomata on their leaves. This carbon dioxide is used in the process of photosynthesis to produce sugars.
Question 6 (Subtopic Code: B7.2)
What is the correct definition of ingestion?
A. The breakdown of large, insoluble food molecules into small, water-soluble molecules.
B. The movement of digested food molecules through the wall of the small intestine into the blood.
C. The passing out of food that has not been digested, as faeces, through the anus.
D. The taking of substances into the body through the mouth.
▶️Answer/Explanation
Answer: D
Explanation: Ingestion refers to the process of taking food or other substances into the body through the mouth. It is the first step in the digestive process.
Question 7 (Subtopic Code: B9.1)
Which statement about the valves found in the human transport system is correct?
A. They are absent in veins.
B. They are present in arteries.
C. They ensure one-way flow of blood.
D. They pump blood from atria to ventricles.
▶️Answer/Explanation
Answer: C
Explanation: Valves in the human transport system, particularly in veins, ensure the one-way flow of blood, preventing backflow and aiding in the return of blood to the heart.
Question 8 (Subtopic Code: B11.1)
Limewater can be used to test for differences in composition between inspired and expired air. Which row is correct?
| Type of Air | Appearance of Limewater | Conclusion |
|---|---|---|
| A. expired | clear to milky | more carbon dioxide present |
| B. expired | milky to clear | more carbon dioxide present |
| C. inspired | clear to milky | more oxygen present |
| D. inspired | milky to clear | more oxygen present |
▶️Answer/Explanation
Answer: A
Explanation: Limewater turns milky in the presence of carbon dioxide. Expired air contains more carbon dioxide than inspired air, so the limewater will turn from clear to milky when testing expired air.
Question 9 (Subtopic Code: B13.1)
In a reflex arc, which structure carries nerve impulses towards the central nervous system?
A. effector
B. motor neurone
C. sensory neurone
D. spinal cord
▶️Answer/Explanation
Answer: C
Explanation: In a reflex arc, sensory neurones carry nerve impulses from the receptors to the central nervous system (CNS). The CNS then processes the information and sends a response via motor neurones to the effectors.
Question 10 (Subtopic Code: B15.3)
The diagram shows a section through an insect-pollinated flower. When pollination occurs, where must the pollen grains reach?
▶️Answer/Explanation
Answer: B
Explanation: In insect-pollinated flowers, pollen grains must reach the stigma (part B) for pollination to occur. The stigma is the receptive surface where pollen grains land and germinate.
Question 11 (Subtopic Code: B16.1)
Which sex chromosomes need to be present in a sperm cell to produce a male zygote?
A. X only
B. Y only
C. XX
D. XY
▶️Answer/Explanation
Answer: B
Explanation: A sperm cell must carry a Y chromosome to produce a male zygote. The combination of an X chromosome from the egg and a Y chromosome from the sperm results in a male (XY).
Question 12 (Subtopic Code: B18.2)
How do herbivores get their energy?
A. by eating animals and plants
B. by eating animals only
C. by eating plants only
D. directly from sunlight
▶️Answer/Explanation
Answer: C
Explanation: Herbivores are organisms that obtain their energy by consuming plants. They are primary consumers in the food chain and rely on plant material for their nutritional needs.
Question 13 (Subtopic: B19.1)
A pupil listed some undesirable effects of deforestation.
- increase of carbon dioxide in the atmosphere
- extinction of species
- flooding
- increased number of habitats
Which effects are correct?
A. 1, 2, 3 and 4
B. 1, 2 and 3 only
C. 1, 2 and 4 only
D. 2, 3 and 4 only
▶️Answer/Explanation
Answer: B
Explanation: Deforestation leads to an increase in carbon dioxide levels, extinction of species, and increased flooding due to the loss of trees. It does not increase the number of habitats; instead, it destroys them.
Question 14 (Subtopic Code: C1.1)
Which process occurs when the arrangement of particles in a substance changes from regular to random?
A. boiling
B. condensing
C. freezing
D. melting
▶️Answer/Explanation
Answer: D
Explanation: Melting is the process where a solid changes to a liquid, and the particles change from a regular arrangement to a more random arrangement as they gain energy.
Question 15 (Subtopic Code: C1.2)
Two substances, X and Y, are heated and then cooled. The observations are shown.
Which type of change occurs when X and Y are heated?
▶️Answer/Explanation
Answer: B
Explanation: Substance X undergoes a chemical change (color change indicates a new substance is formed), while substance Y undergoes a physical change (change of state from solid to vapour).
Question 16 (Subtopic Code: C2.4)
Which diagram represents a fluoride ion?
▶️Answer/Explanation
Answer: D
Explanation: A fluoride ion (F⁻) has gained one electron, giving it a negative charge. Diagram D correctly represents this ion with an extra electron.
Question 17 (Subtopic Code: C4.1)
The electrolysis of concentrated aqueous sodium chloride is shown.
Which statement describes the product at the cathode?
A. It is a colourless gas that pops with a lighted splint.
B. It is a colourless gas that relights a glowing splint.
C. It is a grey solid.
D. It is a pale green gas that bleaches litmus paper.
▶️Answer/Explanation
Answer: A
Explanation: During the electrolysis of concentrated aqueous sodium chloride, hydrogen gas is produced at the cathode. Hydrogen gas is colourless and produces a popping sound when tested with a lighted splint.
Question 18 (Subtopic Code: C5.1)
An acid is added to an alkali until the final solution is just neutral. The reaction is exothermic. Which graph shows how the temperature changes as the acid is being added to the alkali?
▶️Answer/Explanation
Answer: C
Explanation: In an exothermic neutralization reaction, the temperature rises as the acid is added to the alkali, reaching a maximum at the point of neutralization. Graph C correctly shows this trend.
Question 19 (Subtopic Code: C6.3)
In which reaction is zinc being oxidised?
- 2Zn + O₂ → 2ZnO
- ZnO + Mg → Zn + MgO
- Zn + CuO → ZnO + Cu
A. 1 and 2 only
B. 1 and 3 only
C. 2 and 3 only
D. 1, 2 and 3
▶️Answer/Explanation
Answer: B
Explanation: Zinc is oxidized in reactions 1 and 3, where it loses electrons and forms zinc oxide (ZnO). In reaction 2, zinc is reduced as it gains electrons.
Question 20 (Subtopic Code: C7.1)
Which row identifies the types of oxides?
| Acidic Oxides | Basic Oxides |
|---|---|
| A. CaO, Na₂O | CO₂, SO₂ |
| B. CaO, SO₂ | CO₂, Na₂O |
| C. CO₂, Na₂O | CaO, SO₂ |
| D. CO₂, SO₂ | CaO, Na₂O |
▶️Answer/Explanation
Answer: D
Explanation: CO₂ and SO₂ are acidic oxides, while CaO and Na₂O are basic oxides. This is because CO₂ and SO₂ react with water to form acids, whereas CaO and Na₂O react with water to form bases.
Question 21 (Subtopic Code: C7.3)
Hydrochloric acid and sodium hydroxide neutralise each other to form water and sodium chloride. Which method is used to make the solution crystallise?
A. chromatography
B. evaporation
C. filtration
D. fractional distillation
▶️Answer/Explanation
Answer: B
Explanation: Evaporation is used to crystallise sodium chloride from the solution. As the water evaporates, the sodium chloride is left behind in solid form.
Question 22 (Subtopic Code: C8.1)
Which statement about the trends in the Periodic Table is correct?
A. Elements are arranged in order of nucleon number.
B. Elements on the left-hand side form acidic oxides.
C. The melting point of the Group I elements increases down the group.
D. The proton number increases from left to right across the table.
▶️Answer/Explanation
Answer: D
Explanation: The proton number (atomic number) increases from left to right across the Periodic Table. This is the fundamental basis for the arrangement of elements in the Periodic Table.
Question 23 (Subtopic Code: C9.1)
Which statement describes the properties of solid metals?
A. They are brittle and good thermal conductors.
B. They are brittle and poor thermal conductors.
C. They are malleable and good thermal conductors.
D. They are malleable and poor thermal conductors.
▶️Answer/Explanation
Answer: C
Explanation: Solid metals are malleable (can be hammered into shapes) and are good thermal conductors due to the free movement of electrons in their structure.
Question 24 (Subtopic Code: C10.2)
A sample of air is analysed before and after it is used in an experiment. The percentage composition of the air before and after the experiment is recorded. Which process does not produce this change in the composition of the air?
| Gas | Before (%) | After (%) |
|---|---|---|
| Nitrogen | 78 | 78 |
| Oxygen | 21 | 17 |
| Carbon dioxide | 0.04 | 4 |
| Other gases | Small amount | Small amount |
A. combustion of coal
B. combustion of natural gas
C. combustion of sulfur
D. respiration
▶️Answer/Explanation
Answer: C
Explanation: Combustion of sulfur produces sulfur dioxide (SO₂), not carbon dioxide (CO₂). Therefore, it does not explain the increase in carbon dioxide levels observed in the experiment.
Question 25 (Subtopic Code: C10.1)
What is not a use of limestone?
A. manufacture of calcium oxide
B. neutralising industrial waste products
C. purification of water
D. treating acidic soil
▶️Answer/Explanation
Answer: C
Explanation: Limestone is used to manufacture calcium oxide, neutralize industrial waste, and treat acidic soil. However, it is not typically used for water purification.
Question 26 (Subtopic Code: C11.1)
The structures of four compounds are shown.
What are the names of the compounds?
▶️Answer/Explanation
Answer: A
Explanation: Compound 1 is ethane (C₂H₆), compound 2 is ethanol (C₂H₅OH), compound 3 is ethene (C₂H₄), and compound 4 is methane (CH₄).
Question 27 (Subtopic Code: C11.7)
Which two statements describe addition polymers?
- They are large molecules.
- They contain carbon to carbon double bonds.
- They are small molecules.
- They are made from small units.
A. 1 and 2
B. 1 and 4
C. 2 and 3
D. 3 and 4
▶️Answer/Explanation
Answer: B
Explanation: Addition polymers are large molecules made from small repeating units (monomers). They do not necessarily contain carbon-to-carbon double bonds in the final polymer structure.
Question 28 (Subtopic Code: P1.3)
Which statement is correct?
A. Mass is a force and its unit is the kilogram.
B. Mass is a force and its unit is the newton.
C. Weight is a force and its unit is the kilogram.
D. Weight is a force and its unit is the newton.
▶️Answer/Explanation
Answer: D
Explanation: Weight is a force due to gravity, and its unit is the newton (N). Mass, on the other hand, is a measure of the amount of matter and is measured in kilograms (kg).
Question 29 (Subtopic Code: P1.4)
The diagrams show four solid objects of equal mass. Which object is made from the substance with the greatest density?
▶️Answer/Explanation
Answer: A
Explanation: Density is mass per unit volume. Object A has the smallest volume for the same mass, so it has the greatest density.
Question 30 (Subtopic Code: P1.6)
To calculate the work done by a force on an object, the size of the force must be known. Which other quantity must be known?
A. the acceleration of the object in the direction of the force
B. the distance moved by the object in the direction of the force
C. the final speed of the object
D. the time for which the force acts on the object
▶️Answer/Explanation
Answer: B
Explanation: Work done is calculated as force multiplied by the distance moved in the direction of the force. Therefore, the distance moved is required to calculate work done.
Question 31 (Subtopic Code: P1.6)
Which energy source is non-renewable?
A. geothermal
B. hydroelectric
C. nuclear fission
D. wind
▶️Answer/Explanation
Answer: C
Explanation: Nuclear fission relies on uranium, which is a finite resource, making it a non-renewable energy source. Geothermal, hydroelectric, and wind energy are renewable.
Question 32 (Subtopic Code: P3.1)
Diagram 1 represents a wave.
Which diagram represents a wave with twice the frequency and half the amplitude of the wave in diagram 1?
▶️Answer/Explanation
Answer: B
Explanation: A wave with twice the frequency will have more oscillations in the same time period, and half the amplitude will have a smaller peak-to-trough distance. Diagram B matches this description.
Question 33 (Subtopic Code: P3.2)
A student stands in front of a plane mirror on a wall. Which statement about the image of the student is not correct?
A. The image is laterally inverted.
B. The image is smaller than the student.
C. The image is upright.
D. The student and the image are equal distances from the mirror.
▶️Answer/Explanation
Answer: B
Explanation: In a plane mirror, the image is the same size as the object (student). Therefore, the statement that the image is smaller than the student is incorrect.
Question 34 (Subtopic Code: P3.4)
A sports field is next to a large school building. A student at the far side of the sports field sees a groundsman hit a pole with a hammer.
After the hammer hits the pole, the student hears two bangs. Why does the student hear two bangs?
▶️Answer/Explanation
Answer: C
Explanation: The first bang is the direct sound from the hammer hitting the pole, and the second bang is the sound reflected off the school building, which takes longer to reach the student.
Question 35 (Subtopic Code: P4.1)
Which statement about the core of an electromagnet is correct?
A. It is made of soft iron because soft iron is easy to magnetise.
B. It is made of soft iron because soft iron does not lose its magnetism easily.
C. It is made of steel because steel is easy to magnetise.
D. It is made of steel because steel loses its magnetism easily.
▶️Answer/Explanation
Answer: A
Explanation: Soft iron is used in electromagnets because it is easy to magnetise and demagnetise, making it ideal for temporary magnets.
Question 36 (Subtopic Code: P4.4)
The diagram shows the connections to an electric heater. The circuit includes three fuses.
Which of the fuses are correctly placed?
A. fuse 1, fuse 2 and fuse 3
B. fuse 1 and fuse 2 only
C. fuse 1 only
D. fuse 2 only
▶️Answer/Explanation
Answer: C
Explanation: Fuse 1 is correctly placed in the live wire to protect the circuit. Fuse 2 and fuse 3 are not necessary and could cause the circuit to fail unnecessarily.
Question 37 (Subtopic Code: P4.3)
In the circuit, component X is used to control the brightness of the lamp.
What is component X?
A. an ammeter
B. a fixed resistor
C. a fuse
D. a variable resistor
▶️Answer/Explanation
Answer: D
Explanation: A variable resistor is used to control the brightness of a lamp by varying the current flowing through it.
Question 38 (Subtopic Code: P4.2)
A student connects a length of metal resistance wire to a battery.
The student wishes to increase the current in the resistance wire. Which change does this?
A. connecting a second wire in series with the first wire
B. heating the wire
C. making the wire shorter
D. making the wire thinner
▶️Answer/Explanation
Answer: C
Explanation: Making the wire shorter reduces its resistance, which increases the current flowing through it according to Ohm’s Law (V = IR).
Question 39 (Subtopic Code: P5.1)
An atom of an isotope of strontium (Sr) has a proton number of 38 and contains 52 neutrons. What is the nuclide notation for this isotope?
A. \( _{38}^{52}\textrm{Sr}\)
B. \( _{38}^{90}\textrm{Sr}\)
C. \( _{52}^{38}\textrm{Sr}\)
D. \( _{52}^{90}\textrm{Sr}\)
▶️Answer/Explanation
Answer: B
Explanation: The nuclide notation is written as \( \frac{A}{Z} \) X, where A is the mass number (protons + neutrons) and Z is the proton number. For this isotope, A = 38 + 52 = 90, and Z = 38.
Question 40 (Subtopic Code: P5.2)
The half-life of a radioactive isotope is 8.0 days. How long does it take for the activity to decrease to \( \frac{1}{16} \) of its original value?
A. 16 days
B. 24 days
C. 32 days
D. 64 days
▶️Answer/Explanation
Answer: C
Explanation: The activity decreases by half every 8 days. To reach \( \frac{1}{16} \) of the original activity, it takes 4 half-lives (since \( \frac{1}{2^4} = \frac{1}{16} \)). Therefore, 4 × 8 = 32 days.