AQA A-Level Biology 7402/2 Paper 2 Exam Actual 2025
with Detailed Rationales | Complete Exam-Style
Questions | Pass Guaranteed – A+ Graded
SECTION 1: CELL BIOLOGY & TRANSPORT (12 Questions)
Q1: Which organelle is responsible for synthesising proteins destined for secretion
from the cell?
A. Lysosome
B. Golgi apparatus
C. Rough endoplasmic reticulum [CORRECT]
D. Mitochondrion
Correct Answer: C
Rationale: Correct because the rough endoplasmic reticulum is studded with
ribosomes that synthesise proteins which enter the lumen for folding, modification,
and subsequent transport to the Golgi apparatus for secretion.
Q2: During osmosis, water molecules move across a partially permeable membrane
from:
A. A region of low water potential to a region of high water potential
B. A region of high solute concentration to a region of low solute concentration
C. A region of high water potential to a region of low water potential [CORRECT]
,D. A region of low solute concentration to a region of high solute concentration
against the concentration gradient
Correct Answer: C
Rationale: Correct because osmosis is the net movement of water molecules from
an area of higher water potential (lower solute concentration) to an area of lower
water potential (higher solute concentration) down a water potential gradient.
Q3: A student places red blood cells in a solution with a water potential of −150 kPa.
The red blood cells have an internal water potential of −300 kPa. What will happen to
the red blood cells?
A. They will shrink (crenate) as water leaves the cells [CORRECT]
B. They will swell and burst (haemolyse) as water enters the cells
C. They will remain unchanged
D. They will divide by mitosis
Correct Answer: A
Rationale: Correct because water moves from the higher water potential outside the
cell (−150 kPa) to the lower water potential inside the cell (−300 kPa), causing water
to leave the cells and resulting in crenation.
Q4: Which process requires ATP and moves substances against their concentration
gradient?
A. Facilitated diffusion
B. Simple diffusion
C. Active transport [CORRECT]
, D. Osmosis
Correct Answer: C
Rationale: Correct because active transport uses carrier proteins and energy from
ATP hydrolysis to move ions or molecules across a membrane against their
concentration gradient, from low to high concentration.
Q5: In which phase of the cell cycle does DNA replication occur?
A. G1 phase
B. S phase [CORRECT]
C. G2 phase
D. M phase
Correct Answer: B
Rationale: Correct because the S (synthesis) phase is the period during interphase
when DNA replication occurs, ensuring each chromosome consists of two identical
sister chromatids before cell division.
Q6: Which structure forms at the equator of a dividing animal cell during cytokinesis?
A. Cell plate
B. Cleavage furrow [CORRECT]
C. Spindle apparatus
D. Centrosome
Correct Answer: B
with Detailed Rationales | Complete Exam-Style
Questions | Pass Guaranteed – A+ Graded
SECTION 1: CELL BIOLOGY & TRANSPORT (12 Questions)
Q1: Which organelle is responsible for synthesising proteins destined for secretion
from the cell?
A. Lysosome
B. Golgi apparatus
C. Rough endoplasmic reticulum [CORRECT]
D. Mitochondrion
Correct Answer: C
Rationale: Correct because the rough endoplasmic reticulum is studded with
ribosomes that synthesise proteins which enter the lumen for folding, modification,
and subsequent transport to the Golgi apparatus for secretion.
Q2: During osmosis, water molecules move across a partially permeable membrane
from:
A. A region of low water potential to a region of high water potential
B. A region of high solute concentration to a region of low solute concentration
C. A region of high water potential to a region of low water potential [CORRECT]
,D. A region of low solute concentration to a region of high solute concentration
against the concentration gradient
Correct Answer: C
Rationale: Correct because osmosis is the net movement of water molecules from
an area of higher water potential (lower solute concentration) to an area of lower
water potential (higher solute concentration) down a water potential gradient.
Q3: A student places red blood cells in a solution with a water potential of −150 kPa.
The red blood cells have an internal water potential of −300 kPa. What will happen to
the red blood cells?
A. They will shrink (crenate) as water leaves the cells [CORRECT]
B. They will swell and burst (haemolyse) as water enters the cells
C. They will remain unchanged
D. They will divide by mitosis
Correct Answer: A
Rationale: Correct because water moves from the higher water potential outside the
cell (−150 kPa) to the lower water potential inside the cell (−300 kPa), causing water
to leave the cells and resulting in crenation.
Q4: Which process requires ATP and moves substances against their concentration
gradient?
A. Facilitated diffusion
B. Simple diffusion
C. Active transport [CORRECT]
, D. Osmosis
Correct Answer: C
Rationale: Correct because active transport uses carrier proteins and energy from
ATP hydrolysis to move ions or molecules across a membrane against their
concentration gradient, from low to high concentration.
Q5: In which phase of the cell cycle does DNA replication occur?
A. G1 phase
B. S phase [CORRECT]
C. G2 phase
D. M phase
Correct Answer: B
Rationale: Correct because the S (synthesis) phase is the period during interphase
when DNA replication occurs, ensuring each chromosome consists of two identical
sister chromatids before cell division.
Q6: Which structure forms at the equator of a dividing animal cell during cytokinesis?
A. Cell plate
B. Cleavage furrow [CORRECT]
C. Spindle apparatus
D. Centrosome
Correct Answer: B
