1|Page
HESI A2 BIOLOGY NEWEST EXAM 2026 | 150
QUESTIONS AND CORRECT DETAILED
ANSWERS | RATED A +
This exam is a fully comprehensive, exam-ready Biology assessment
designed to mirror the structure, rigor, and cognitive demands of the
HESI A2 Biology examination. It evaluates foundational biological
principles, applied knowledge, and scenario-based reasoning expected of
candidates preparing for nursing and allied health programs. The exam
covers cellular biology, biochemistry, enzymes, metabolism, genetics,
DNA/RNA, mitosis and meiosis, protein synthesis, homeostasis,
evolution, and scientific reasoning as tested on recent HESI A2 exams.
Questions balance recall, application, and critical thinking to ensure
readiness for real exam conditions and professional healthcare education
standards.
1. Which level of biological organization represents the simplest form
capable of performing all life processes?
A. Tissue
B. Cell
C. Organ
D. Organelle
Italicized rationale: Cells are the smallest units capable of
carrying out all essential life functions independently.
2. A red blood cell lacks a nucleus primarily to:
A. Increase DNA replication
B. Improve immune response
C. Maximize space for hemoglobin
D. Enhance protein synthesis
Italicized rationale: The absence of a nucleus allows more room
for hemoglobin, increasing oxygen-carrying capacity.
,2|Page
3. Which organelle is responsible for ATP production in eukaryotic
cells?
A. Ribosome
B. Golgi apparatus
C. Mitochondrion
D. Lysosome
Italicized rationale: Mitochondria are the site of cellular
respiration and ATP generation.
4. Diffusion is best described as the movement of molecules:
A. Against a concentration gradient
B. From high to low concentration
C. Using ATP
D. Through protein pumps only
Italicized rationale: Diffusion occurs passively down a
concentration gradient without energy input.
5. Which macromolecule provides long-term energy storage?
A. Proteins
B. Nucleic acids
C. Lipids
D. Carbohydrates
Italicized rationale: Lipids store more energy per gram than
carbohydrates and serve as long-term energy reserves.
6. Enzymes function by:
A. Increasing activation energy
B. Lowering activation energy
C. Being consumed in reactions
D. Changing reaction products
Italicized rationale: Enzymes speed reactions by lowering the
energy barrier without being consumed.
7. Which pH environment would most likely denature an enzyme?
A. Neutral pH
B. Optimal pH
C. Extreme acidic or basic pH
D. Slightly alkaline pH
, 3|Page
Italicized rationale: Extreme pH disrupts enzyme structure,
altering the active site.
8. Osmosis specifically refers to the movement of:
A. Solutes across membranes
B. Water across a semipermeable membrane
C. Ions through channels
D. Proteins through vesicles
Italicized rationale: Osmosis is the diffusion of water across a
selectively permeable membrane.
9. A solution with a higher solute concentration than the cell is:
A. Hypotonic
B. Hypertonic
C. Isotonic
D. Neutral
Italicized rationale: Hypertonic solutions cause water to leave the
cell.
10. Which phase of mitosis involves chromosome alignment at
the equator?
A. Prophase
B. Metaphase
C. Anaphase
D. Telophase
Italicized rationale: Chromosomes line up at the metaphase plate
during metaphase.
11. Meiosis differs from mitosis because meiosis:
A. Produces identical cells
B. Occurs in somatic cells
C. Produces haploid cells
D. Does not involve DNA replication
Italicized rationale: Meiosis reduces chromosome number by
half, producing gametes.
12. DNA replication occurs during which cell cycle phase?
A. G1
B. S phase
C. G2
HESI A2 BIOLOGY NEWEST EXAM 2026 | 150
QUESTIONS AND CORRECT DETAILED
ANSWERS | RATED A +
This exam is a fully comprehensive, exam-ready Biology assessment
designed to mirror the structure, rigor, and cognitive demands of the
HESI A2 Biology examination. It evaluates foundational biological
principles, applied knowledge, and scenario-based reasoning expected of
candidates preparing for nursing and allied health programs. The exam
covers cellular biology, biochemistry, enzymes, metabolism, genetics,
DNA/RNA, mitosis and meiosis, protein synthesis, homeostasis,
evolution, and scientific reasoning as tested on recent HESI A2 exams.
Questions balance recall, application, and critical thinking to ensure
readiness for real exam conditions and professional healthcare education
standards.
1. Which level of biological organization represents the simplest form
capable of performing all life processes?
A. Tissue
B. Cell
C. Organ
D. Organelle
Italicized rationale: Cells are the smallest units capable of
carrying out all essential life functions independently.
2. A red blood cell lacks a nucleus primarily to:
A. Increase DNA replication
B. Improve immune response
C. Maximize space for hemoglobin
D. Enhance protein synthesis
Italicized rationale: The absence of a nucleus allows more room
for hemoglobin, increasing oxygen-carrying capacity.
,2|Page
3. Which organelle is responsible for ATP production in eukaryotic
cells?
A. Ribosome
B. Golgi apparatus
C. Mitochondrion
D. Lysosome
Italicized rationale: Mitochondria are the site of cellular
respiration and ATP generation.
4. Diffusion is best described as the movement of molecules:
A. Against a concentration gradient
B. From high to low concentration
C. Using ATP
D. Through protein pumps only
Italicized rationale: Diffusion occurs passively down a
concentration gradient without energy input.
5. Which macromolecule provides long-term energy storage?
A. Proteins
B. Nucleic acids
C. Lipids
D. Carbohydrates
Italicized rationale: Lipids store more energy per gram than
carbohydrates and serve as long-term energy reserves.
6. Enzymes function by:
A. Increasing activation energy
B. Lowering activation energy
C. Being consumed in reactions
D. Changing reaction products
Italicized rationale: Enzymes speed reactions by lowering the
energy barrier without being consumed.
7. Which pH environment would most likely denature an enzyme?
A. Neutral pH
B. Optimal pH
C. Extreme acidic or basic pH
D. Slightly alkaline pH
, 3|Page
Italicized rationale: Extreme pH disrupts enzyme structure,
altering the active site.
8. Osmosis specifically refers to the movement of:
A. Solutes across membranes
B. Water across a semipermeable membrane
C. Ions through channels
D. Proteins through vesicles
Italicized rationale: Osmosis is the diffusion of water across a
selectively permeable membrane.
9. A solution with a higher solute concentration than the cell is:
A. Hypotonic
B. Hypertonic
C. Isotonic
D. Neutral
Italicized rationale: Hypertonic solutions cause water to leave the
cell.
10. Which phase of mitosis involves chromosome alignment at
the equator?
A. Prophase
B. Metaphase
C. Anaphase
D. Telophase
Italicized rationale: Chromosomes line up at the metaphase plate
during metaphase.
11. Meiosis differs from mitosis because meiosis:
A. Produces identical cells
B. Occurs in somatic cells
C. Produces haploid cells
D. Does not involve DNA replication
Italicized rationale: Meiosis reduces chromosome number by
half, producing gametes.
12. DNA replication occurs during which cell cycle phase?
A. G1
B. S phase
C. G2
