AQA A LEVEL BIOLOGY PAPER 1,2&3
2026 ASSESSMENT QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES ||
100% GUARANTEED PASS!!
<LATEST VERSION>
PAPER 1
1. Which of the following is a function of carbohydrates in cells?
A) Catalyzing reactions
B) Storing genetic information
C) Providing energy
D) Acting as a receptor
Answer: C) Providing energy
Rationale: Carbohydrates like glucose provide energy via respiration and can be
stored as glycogen or starch. Proteins catalyze reactions (A), DNA stores genetic
information (B), and receptors are proteins (D).
2. Which type of bond holds complementary base pairs in DNA together?
A) Covalent bond
B) Hydrogen bond
C) Ionic bond
, D) Peptide bond
Answer: B) Hydrogen bond
Rationale: Hydrogen bonds between A-T (2 bonds) and C-G (3 bonds) stabilize
the DNA double helix while allowing strand separation during replication.
3. During which stage of the cell cycle does DNA replicate?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
Answer: B) S phase
Rationale: The S (synthesis) phase ensures each daughter cell receives an exact
copy of the genome.
4. Which organelle is responsible for ATP production?
A) Nucleus
B) Mitochondrion
C) Ribosome
D) Golgi apparatus
Answer: B) Mitochondrion
Rationale: Mitochondria produce ATP through aerobic respiration via the electron
transport chain.
,5. Which property of water makes it important in transport in plants?
A) High specific heat capacity
B) Cohesion and adhesion
C) Low density as a solid
D) Non-polarity
Answer: B) Cohesion and adhesion
Rationale: Cohesion allows water molecules to stick together; adhesion allows
water to climb xylem walls via capillary action.
6. Which type of RNA carries the genetic code from DNA to the ribosome?
A) rRNA
B) tRNA
C) mRNA
D) siRNA
Answer: C) mRNA
Rationale: mRNA transcribes the DNA code and transports it to ribosomes for
protein synthesis.
7. The rate of diffusion is affected by which factors?
A) Concentration gradient
B) Temperature
C) Surface area
D) All of the above
Answer: D) All of the above
Rationale: Higher concentration gradients, increased temperatures, and larger
surface areas all increase diffusion rates.
, 8. Which of the following is a feature of prokaryotic cells?
A) Membrane-bound nucleus
B) Circular DNA
C) Mitochondria
D) Linear chromosomes
Answer: B) Circular DNA
Rationale: Prokaryotes lack a nucleus and mitochondria. Their DNA is circular,
while eukaryotic chromosomes are linear.
9. Which enzyme breaks down hydrogen peroxide in cells?
A) Catalase
B) Amylase
C) Lipase
D) DNA polymerase
Answer: A) Catalase
Rationale: Catalase decomposes hydrogen peroxide, a toxic by-product of
metabolism, into water and oxygen.
10. Which molecule is a monomer of proteins?
A) Glucose
B) Amino acid
C) Nucleotide
D) Fatty acid
Answer: B) Amino acid
Rationale: Proteins are polymers of amino acids joined by peptide bonds.
2026 ASSESSMENT QUESTIONS AND CORRECT
DETAILED ANSWERS WITH RATIONALES ||
100% GUARANTEED PASS!!
<LATEST VERSION>
PAPER 1
1. Which of the following is a function of carbohydrates in cells?
A) Catalyzing reactions
B) Storing genetic information
C) Providing energy
D) Acting as a receptor
Answer: C) Providing energy
Rationale: Carbohydrates like glucose provide energy via respiration and can be
stored as glycogen or starch. Proteins catalyze reactions (A), DNA stores genetic
information (B), and receptors are proteins (D).
2. Which type of bond holds complementary base pairs in DNA together?
A) Covalent bond
B) Hydrogen bond
C) Ionic bond
, D) Peptide bond
Answer: B) Hydrogen bond
Rationale: Hydrogen bonds between A-T (2 bonds) and C-G (3 bonds) stabilize
the DNA double helix while allowing strand separation during replication.
3. During which stage of the cell cycle does DNA replicate?
A) G1 phase
B) S phase
C) G2 phase
D) M phase
Answer: B) S phase
Rationale: The S (synthesis) phase ensures each daughter cell receives an exact
copy of the genome.
4. Which organelle is responsible for ATP production?
A) Nucleus
B) Mitochondrion
C) Ribosome
D) Golgi apparatus
Answer: B) Mitochondrion
Rationale: Mitochondria produce ATP through aerobic respiration via the electron
transport chain.
,5. Which property of water makes it important in transport in plants?
A) High specific heat capacity
B) Cohesion and adhesion
C) Low density as a solid
D) Non-polarity
Answer: B) Cohesion and adhesion
Rationale: Cohesion allows water molecules to stick together; adhesion allows
water to climb xylem walls via capillary action.
6. Which type of RNA carries the genetic code from DNA to the ribosome?
A) rRNA
B) tRNA
C) mRNA
D) siRNA
Answer: C) mRNA
Rationale: mRNA transcribes the DNA code and transports it to ribosomes for
protein synthesis.
7. The rate of diffusion is affected by which factors?
A) Concentration gradient
B) Temperature
C) Surface area
D) All of the above
Answer: D) All of the above
Rationale: Higher concentration gradients, increased temperatures, and larger
surface areas all increase diffusion rates.
, 8. Which of the following is a feature of prokaryotic cells?
A) Membrane-bound nucleus
B) Circular DNA
C) Mitochondria
D) Linear chromosomes
Answer: B) Circular DNA
Rationale: Prokaryotes lack a nucleus and mitochondria. Their DNA is circular,
while eukaryotic chromosomes are linear.
9. Which enzyme breaks down hydrogen peroxide in cells?
A) Catalase
B) Amylase
C) Lipase
D) DNA polymerase
Answer: A) Catalase
Rationale: Catalase decomposes hydrogen peroxide, a toxic by-product of
metabolism, into water and oxygen.
10. Which molecule is a monomer of proteins?
A) Glucose
B) Amino acid
C) Nucleotide
D) Fatty acid
Answer: B) Amino acid
Rationale: Proteins are polymers of amino acids joined by peptide bonds.
