Question 1 (B1.1)
What is a plant demonstrating when carbon dioxide is released from its cells?
A. assimilation
B. egestion
C. excretion
D. nutrition
▶️Answer/Explanation
Answer: C
Explanation: Excretion is the removal of waste products of metabolism, such as carbon dioxide from respiration. Assimilation involves incorporating nutrients into cells, egestion removes undigested food, and nutrition is the intake of food materials.
Question 2 (B2.1)
The diagram shows a section through a cell.
What shows that this is a plant cell?
A. It has a cell membrane.
B. It has a nucleus.
C. It has a permanent vacuole.
D. It has cytoplasm.
▶️Answer/Explanation
Answer: C
Explanation: While both plant and animal cells have a cell membrane, nucleus, and cytoplasm, only plant cells typically have a large permanent vacuole that occupies most of the cell’s volume.
Question 3 (B4.1)
Which result with the biuret test shows that protein is present?
A. blue
B. green
C. orange
D. purple
▶️Answer/Explanation
Answer: D
Explanation: The biuret test turns purple in the presence of proteins due to the formation of a copper-peptide complex. Blue indicates no protein, while green and orange are not typical results of this test.
Question 4 (B5.1)
Four test-tubes were set up to investigate the effect of pH on the digestion of protein by the enzyme pepsin. Each test-tube contained the same volumes of cloudy egg white suspension and pepsin solution. The temperature in each tube was the same but the pH differed as shown.
In which test-tube would the suspension clear first?
A. pH 2
B. pH 5
C. pH 8
D. pH 11
▶️Answer/Explanation
Answer: A
Explanation: Pepsin works optimally at pH 2, which is the acidic environment of the stomach. At this pH, it breaks down proteins most efficiently, causing the egg white suspension to clear fastest.
Question 5 (B6.1)
Green plants need magnesium ions. Which plant process is limited when magnesium is deficient?
A. meiosis
B. photosynthesis
C. pollination
D. respiration
▶️Answer/Explanation
Answer: B
Explanation: Magnesium is a central component of chlorophyll, the pigment essential for photosynthesis. Without sufficient magnesium, chlorophyll production decreases, limiting photosynthesis.
Question 6 (B7.2)
Where is bile stored?
A. gall bladder
B. liver
C. pancreas
D. stomach
▶️Answer/Explanation
Answer: A
Explanation: While bile is produced in the liver, it is stored and concentrated in the gall bladder before being released into the small intestine to emulsify fats.
Question 7 (B8.1)
The diagrams show sections through a stem and a root.
Which indicate the positions of the xylem?
A. P and S
B. P and T
C. Q and S
D. Q and T
▶️Answer/Explanation
Answer: B
Explanation: In both stems and roots, xylem is typically located toward the center of the vascular bundle (P in stem) and in the center of the root (T). Phloem is usually found toward the outside.
Question 8 (B12.1)
What are the products of the anaerobic respiration of glucose in yeast?
A. alcohol and carbon dioxide
B. alcohol only
C. lactic acid and carbon dioxide
D. lactic acid only
▶️Answer/Explanation
Answer: A
Explanation: Yeast undergoes alcoholic fermentation during anaerobic respiration, producing ethanol (alcohol) and carbon dioxide. Lactic acid is produced by animal cells during anaerobic respiration.
Question 9 (B13.1)
Which actions are voluntary and which are involuntary?
| a change in pupil size due to a change in light intensity | the lens in the eye changing shape during accommodation | |
| A | involuntary | involuntary |
| B | involuntary | voluntary |
| C | voluntary | involuntary |
| D | voluntary | voluntary |
▶️Answer/Explanation
Answer: A
Explanation: Both pupil size adjustment (pupillary reflex) and lens accommodation are automatic, involuntary responses controlled by the autonomic nervous system to optimize vision under different conditions.
Question 10 (B15.3)
The diagram shows a type of reproduction.
Which row is correct for this type of reproduction?
▶️Answer/Explanation
Ans: C
Question 11 (B16.1)
A body cell taken from a male kangaroo contains 16 chromosomes in the nucleus.
How many chromosomes would be found in the nucleus of a sperm cell from the same kangaroo and what term describes this number?
▶️Answer/Explanation
Answer: B
Explanation: Sperm cells are gametes, which are haploid (half the chromosome number of body cells). Since the body cell has 16 chromosomes (diploid), the sperm cell would have 8 chromosomes (haploid).
Question 12 (B18.2)
In the food chain shown, 10% of the energy is transferred between each trophic level.
grass → grasshopper → frog → snake → buzzard
For every 100 kJ of energy in the herbivore, how much energy will be transferred to the tertiary consumer?
A. 0.1 kJ
B. 1 kJ
C. 10 kJ
D. 100 kJ
▶️Answer/Explanation
Answer: B
Explanation: The herbivore (grasshopper) is the primary consumer (100 kJ). The frog (secondary consumer) receives 10% = 10 kJ. The snake (tertiary consumer) receives 10% of 10 kJ = 1 kJ.
Question 13 (B18.3)
The diagram shows some of the processes in the carbon cycle.
Which process is respiration?
▶️Answer/Explanation
Answer: C
Explanation: Respiration is the process where organisms release carbon dioxide into the atmosphere. Option C shows animals producing carbon dioxide, which is the result of respiration.
Question 14 (C1.1)
Which property of a substance is used to determine that it is pure?
A. colour
B. melting point
C. pH
D. shape of the crystals
▶️Answer/Explanation
Answer: B
Explanation: Pure substances have sharp, well-defined melting points. Impure substances melt over a range of temperatures, so melting point is the best indicator of purity.
Question 15 (C6.1)
Which processes are chemical changes?
1. conversion of steam to liquid water
2. cracking of alkanes
3. fractional distillation of petroleum
4. thermal decomposition of calcium carbonate
A. 1 and 3
B. 1 and 4
C. 2 and 3
D. 2 and 4
▶️Answer/Explanation
Answer: D
Explanation: Chemical changes form new substances. Cracking alkanes (2) and thermal decomposition of calcium carbonate (4) both produce new substances. The other options are physical changes.
Question 16 (C2.6)
Silicon(IV) oxide has a giant molecular structure.
Which row is correct?
| number of oxygen atoms bonded to each silicon atom | number of silicon atoms bonded to each oxygen atom | |
|---|---|---|
| A | 2 | 2 |
| B | 2 | 4 |
| C | 4 | 2 |
| D | 4 | 4 |
▶️Answer/Explanation
Answer: C
Explanation: In silicon(IV) oxide, each silicon atom forms 4 covalent bonds with oxygen atoms (SiO₄), and each oxygen atom forms 2 bonds (bridging between silicon atoms).
Question 17 (C3.3)
Which sample does not contain two moles of hydrogen atoms?
A. Avogadro’s number of hydrogen molecules
B. 1 g of hydrogen molecules
C. 18 g of water molecules
D. 24 dm³ hydrogen molecules at room temperature and pressure
▶️Answer/Explanation
Answer: B
Explanation: A) H₂ molecules: 1 mole = 2 moles H atoms B) 1 g H₂ = 0.5 mole H₂ = 1 mole H atoms C) 18 g H₂O = 1 mole H₂O = 2 moles H atoms D) 24 dm³ H₂ at RTP = 1 mole H₂ = 2 moles H atoms
Question 18 (C4.1)
Concentrated aqueous sodium chloride is electrolysed using inert electrodes.
Which row describes how the number of sodium ions and of chloride ions changes during the electrolysis?
| number of sodium ions | number of chloride ions | |
|---|---|---|
| A | decreases | decreases |
| B | decreases | no change |
| C | no change | decreases |
| D | no change | no change |
▶️Answer/Explanation
Answer: C
Explanation: In the electrolysis of concentrated NaCl solution: – Na⁺ ions are not discharged (H⁺ from water is discharged instead at cathode) – Cl⁻ ions are discharged at anode (2Cl⁻ → Cl₂ + 2e⁻), so their number decreases
Question 19 (C6.3)
A redox reaction is shown.
Fe + Cu²⁺ → Fe²⁺ + Cu
Which substance is the reducing agent?
A. Cu
B. Cu²⁺
C. Fe
D. Fe²⁺
▶️Answer/Explanation
Answer: C
Explanation: The reducing agent is the species that gets oxidized (loses electrons). Here, Fe is oxidized to Fe²⁺ (loses 2e⁻) while reducing Cu²⁺ to Cu.
Question 20 (C12.3)
The colours in an ink can be separated by chromatography.
Which diagram shows the correct way to set up the apparatus?
▶️Answer/Explanation
Answer: C
Explanation: In chromatography, the ink spot should be just above the solvent surface (not touching it initially) to allow the solvent to rise up the paper by capillary action and separate the components.
Question 21 (C8.1)
Which statement about the Periodic Table is correct?
A. Elements are listed in order of neutron number.
B. Elements are listed in order of nucleon number.
C. Elements are listed in order of proton number.
D. Elements are listed in order of relative atomic mass.
▶️Answer/Explanation
Answer: C
Explanation: The Periodic Table arranges elements in order of increasing proton number (atomic number), which is unique for each element and determines its position in the table. While relative atomic mass generally increases with proton number, there are exceptions (like tellurium and iodine), making proton number the definitive ordering criterion.
Question 22 (C8.2)
Which row describes a Group II element in period 3 of the Periodic Table?
| electrical conductivity | number of outer shell electrons | |
|---|---|---|
| A | good | 2 |
| B | good | 3 |
| C | poor | 2 |
| D | poor | 3 |
▶️Answer/Explanation
Answer: A
Explanation: The Group II element in period 3 is magnesium. All Group II elements (alkaline earth metals) have 2 outer shell electrons and are good conductors of electricity due to their metallic bonding with delocalized electrons.
Question 23 (C9.1)
Which statement describes all metals?
A. They break when hit with a hammer.
B. They conduct electricity.
C. They dissolve in water.
D. They have high densities.
▶️Answer/Explanation
Answer: B
Explanation: All metals conduct electricity due to their delocalized electrons. While many metals are malleable (A is false), not all dissolve in water (C is false), and some like lithium have low densities (D is false).
Question 24 (C9.4)
Which pair of substances do not react with each other?
A. copper and aqueous magnesium sulfate
B. iron and aqueous copper(II) sulfate
C. magnesium and aqueous zinc sulfate
D. zinc and aqueous iron(II) sulfate
▶️Answer/Explanation
Answer: A
Explanation: Copper is below magnesium in the reactivity series, so it cannot displace magnesium from its compound. The other pairs will react as the more reactive metal (Fe, Mg, Zn) displaces the less reactive one from solution.
Question 25 (C6.3)
Which processes produce carbon dioxide?
1. acid reacting with a metal
2. respiration
3. combustion of ethanol
4. acid reacting with a metal oxide
A. 1 and 2
B. 1 and 4
C. 2 and 3
D. 3 and 4
▶️Answer/Explanation
Answer: C
Explanation: Respiration (2) and combustion of organic compounds like ethanol (3) produce CO₂. Acids reacting with metals typically produce hydrogen gas (1), while acids reacting with metal oxides produce salt and water (4).
Question 26 (C11.2)
Which structure represents ethanol?
▶️Answer/Explanation
Answer: D
Explanation: Ethanol has the molecular formula C₂H₅OH. Option D correctly shows two carbon atoms single-bonded to each other, with one carbon bonded to an -OH group (hydroxyl group) and the remaining bonds filled with hydrogen atoms.
Question 27 (C11.7)
A section of a polymer chain is shown.
Which monomer is used to make this polymer?
▶️Answer/Explanation
Answer: B
Explanation: The polymer shown is poly(chloroethene) or PVC, formed by addition polymerization of chloroethene (CH₂=CHCl) monomers. The double bond in the monomer opens up to form the repeating -CH₂-CHCl- units in the polymer chain.
Question 28 (P1.5.1)
There is no resultant force acting on a body. Which statement is correct?
A. The body is either at rest or moving at constant speed in a straight line.
B. The body must be at rest.
C. The body is gaining speed.
D. The body is losing speed.
▶️Answer/Explanation
Answer: A
Explanation: Newton’s First Law states that with no resultant force, a body maintains its state of motion – either remaining at rest or continuing to move at constant velocity (constant speed in a straight line). Acceleration (C or D) would require a resultant force.
Question 29 (P1.5.1)
Diagram 1 shows a spring with its length indicated. Diagram 2 shows the same spring with a 20 N load hung from it, and the new length of the spring.
The spring obeys Hooke’s Law.
Which graph is the extension-load graph for the spring?
▶️Answer/Explanation
Answer: A
Explanation: The question states the spring obeys Hooke’s Law (F = kx), which means extension is directly proportional to load, giving a straight-line graph through the origin. The gradient equals 1/k (spring constant).
Question 30 (P1.6.1)
A body moving at speed v has kinetic energy E. What is the speed of the body when its kinetic energy is 4.0 E?
A. 0.25 v
B. 2.0 v
C. 4.0 v
D. 16 v
▶️Answer/Explanation
Answer: B
Explanation: Kinetic energy E = ½mv². For energy to become 4E, v² must become 4v² (since mass is constant), so the new speed is √4v² = 2v. Kinetic energy depends on the square of velocity.
Question 31 (P1.6.4)
A student wishes to measure his average power when running up a flight of steps. The energy transferred is 7.0 kJ and the time taken is 14 seconds.
What is the student’s average power?
A. 0.0020 W
B. 98 W
C. 500 W
D. 98.000 W
▶️Answer/Explanation
Answer: C
Explanation: Power is calculated using the formula: Power = Energy / Time. Here, Energy = 7.0 kJ = 7000 J and Time = 14 s. Thus, Power = 7000 J / 14 s = 500 W.
Question 32 (P3.2.2)
A glass block is surrounded by air. Light travelling in the glass block reaches the edge of the block. The critical angle of the glass is 42°.
Which row shows an angle of incidence i of the light and what happens to the light when it reaches the edge of the glass block at this angle of incidence?
| i | what happens to the light | |
|---|---|---|
| A | 30° | totally internally reflected |
| B | 45° | refracted |
| C | 60° | totally internally reflected |
| D | 75° | refracted |
▶️Answer/Explanation
Answer: C
Explanation: Total internal reflection occurs when the angle of incidence is greater than the critical angle (42°). At 60° (which is >42°), the light will be totally internally reflected. At angles less than the critical angle (like 30° and 45°), the light will be refracted.
Question 33 (P3.2.3)
Which statement about real and virtual images formed by a thin converging lens is correct?
A. All real images are enlarged and inverted.
B. All real images can be produced on a screen.
C. All virtual images are diminished and upright.
D. All virtual images can be produced on a screen.
▶️Answer/Explanation
Answer: B
Explanation: Real images formed by a converging lens can always be projected onto a screen because the light rays actually converge at the image location. Virtual images cannot be projected onto a screen as the light rays only appear to diverge from the image location.
Question 34 (P4.2.4)
Which graph is the current-voltage characteristic of a filament lamp?
▶️Answer/Explanation
Answer: D
Explanation: A filament lamp shows a non-linear I-V characteristic because as current increases, the filament heats up and its resistance increases. This results in a curve that flattens as voltage increases, which is best represented by graph D.
Question 35 (P4.3.2)
The diagram shows a circuit containing two switches P and Q, and three lamps. One lamp is labelled X.
Which of the switches must be closed so that only lamp X is lit?
A. neither switch
B. switch P only
C. switch Q only
D. switch P and switch Q
▶️Answer/Explanation
Answer: D
Explanation: For only lamp X to be lit, the circuit must be completed through X while preventing current from flowing through the other lamps. This typically requires both switches to be in specific positions (both closed in this case) to create the correct path.
Question 36 (P4.3.2)
Which row shows how lamps are connected in a lighting circuit in a house and gives an advantage of connecting them in this way?
| how lamps are connected | advantage of connecting them in this way | |
|---|---|---|
| A | in parallel | they can be switched separately |
| B | in parallel | they share the voltage |
| C | in series | they can be switched separately |
| D | in series | they share the voltage |
▶️Answer/Explanation
Answer: A
Explanation: House lighting circuits use parallel connections so that each lamp can be switched independently and the failure of one lamp doesn’t affect the others. They don’t share voltage in parallel – each gets the full supply voltage.
Question 37 (P4.4)
An electrical extension block has four sockets, a cable which can safely take a current of 6A and a plug. It is protected by a fuse rated at 5A.
The extension block is used with four appliances and the 5A fuse blows. The owner replaces the 5A fuse with a 13A fuse.
Why is the extension block now dangerous?
A. The appliances may overheat before the fuse blows.
B. The cable may overheat before the fuse blows.
C. The sockets may burn out before the fuse blows.
D. The 13A fuse may blow too soon.
▶️Answer/Explanation
Answer: B
Explanation: The cable is only rated for 6A. With a 13A fuse, the cable could carry much more current than it’s designed for, causing overheating and potential fire risk before the fuse would blow at 13A.
Question 38 (P4.5.4)
The diagram shows a current-carrying conductor between the poles of a magnet. The direction of the current is shown.
In which direction is the force that acts on the wire?
A. into the page
B. out of the page
C. to the left
D. to the right
▶️Answer/Explanation
Answer: A
Explanation: Using Fleming’s Left-Hand Rule: the magnetic field is from N to S (left to right), current is upwards, so the force is into the page.
Question 39 (P4.5.2)
Which graph shows the output voltage from a simple a.c. generator?
▶️Answer/Explanation
Answer: D
Explanation: A simple AC generator produces a sinusoidal (sine wave) output voltage that alternates between positive and negative values, which is shown in graph D.
Question 40 (P5.2.2)
Which type of radiation has the greatest ionising effect, and which is the most penetrating?
| greatest ionising effect | most penetrating | |
|---|---|---|
| A | α-particles | α-particles |
| B | α-particles | γ-rays |
| C | γ-rays | α-particles |
| D | γ-rays | γ-rays |
▶️Answer/Explanation
Answer: B
Explanation: Alpha particles have the greatest ionizing effect due to their large mass and charge, while gamma rays are the most penetrating as they have no charge and minimal mass.