Question 1 (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 (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, the cell needs oxygen and glucose. Oxygen diffuses into the cell from the blood capillary, and glucose is transported into the cell for energy production.
Question 3 (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, which are primarily composed of carbon, hydrogen, and oxygen.
Question 4 (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.
Question 5 (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 openings called stomata on their leaves. This carbon dioxide is used in the process of photosynthesis to produce sugars.
Question 6 (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 (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 that blood flows in one direction, preventing backflow and maintaining efficient circulation.
Question 8 (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: Expired air contains more carbon dioxide than inspired air. When limewater is exposed to expired air, it turns from clear to milky due to the formation of calcium carbonate, indicating the presence of carbon dioxide.
Question 9 (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 receptors towards the central nervous system (CNS), where the information is processed.
Question 10 (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 pollination, pollen grains must reach the stigma (part B) of the flower, where they can germinate and grow a pollen tube to fertilize the ovule.
Question 11 (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 carrying a Y chromosome will result in a male zygote (XY) when it fertilizes an egg (which always carries an X chromosome).
Question 12 (B18.1)
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.
Question 13 (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 (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.
Question 15 (C2.1)
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), while substance Y undergoes a physical change (change of state from solid to vapor).
Question 16 (C2.4)
Which diagram represents a fluoride ion?
▶️Answer/Explanation
Answer: A
Explanation: A fluoride ion is formed when a fluorine atom gains one electron, resulting in a negative charge (F–).
Question 17 (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 is a colourless gas that pops with a lighted splint.
Question 18 (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 until the solution is neutral. After neutralization, the temperature remains constant or decreases slightly.
Question 19 (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: In reactions 1 and 3, zinc (Zn) loses electrons and is oxidized to form zinc oxide (ZnO). In reaction 2, zinc is reduced, not oxidized.
Question 20 (C7.2)
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: Acidic oxides (e.g., CO2, SO2) are typically formed by non-metals, while basic oxides (e.g., CaO, Na2O) are formed by metals.
Question 21 (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 forms crystals.
Question 22 (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, as elements are arranged in order of increasing atomic number.
Question 23 (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.
Question 24 (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.
| Gas | Before (%) | After (%) |
|---|---|---|
| nitrogen | 78 | 78 |
| oxygen | 21 | 17 |
| carbon dioxide | 0.04 | 4 |
| other gases | small amount | small amount |
Which process does not produce this change in the composition of the air?
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). The increase in CO2 and decrease in O2 suggest processes like respiration or combustion of hydrocarbons.
Question 25 (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, neutralise acidic waste, and treat acidic soil, but it is not typically used for water purification.
Question 26 (C11.2)
The structures of four compounds are shown.
What are the names of the compounds?
▶️Answer/Explanation
Answer: A
Explanation: The compounds are correctly identified as ethane (C2H6), ethanol (C2H5OH), ethene (C2H4), and methane (CH4).
Question 27 (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-carbon double bonds in the final polymer structure.
Question 28 (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 is a measure of the quantity of matter, and its unit is the kilogram (kg).
Question 29 (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 (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 × distance moved in the direction of the force. Therefore, the distance moved is required.
Question 31 (P1.6.3)
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 non-renewable. Geothermal, hydroelectric, and wind energy are renewable sources.
Question 32 (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 waves in the same time period, and half the amplitude will have a smaller vertical displacement. Diagram B matches this description.
Question 33 (P3.2.1)
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: The image formed by a plane mirror is the same size as the object, upright, laterally inverted, and located at the same distance behind the mirror as the object is in front of it.
Question 34 (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 sound reaching the student directly, and the second bang is the sound reflected off the school building, which takes longer to reach the student.
Question 35 (P4.5.1)
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 the core of an electromagnet because it is easy to magnetise and demagnetise, making it ideal for temporary magnets.
Question 36 (P4.3.2)
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 if they blow.
Question 37 (P4.3.2)
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 the circuit.
Question 38 (P4.2.4)
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 according to Ohm’s Law (V = IR).
Question 39 (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. 5238Sr
B. 9038Sr
C. 3852Sr
D. 9052Sr
▶️Answer/Explanation
Answer: B
Explanation: The nuclide notation is written as AZX, where A is the mass number (protons + neutrons = 38 + 52 = 90), Z is the proton number (38), and X is the element symbol (Sr).
Question 40 (P5.2.4)
The half-life of a radioactive isotope is 8.0 days. How long does it take for the activity to decrease to 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 a factor of 1/16 after 4 half-lives (since 1/16 = (1/2)4). Therefore, the time taken is 4 × 8.0 days = 32 days.