HESI A2 Biology Practice Test: Free Timed Drill

What is on the HESI A2 Biology section?

About 30 questions in 25 minutes, 25 or so scored, on 6 topics: biomolecules and water, cells and organelles, membranes and transport, metabolism, cell division and genetics, dna and protein synthesis.

HESI A2 Biology, as schools describe it, with where each fact comes from
Questions	30 shown, about 25 scored; the unscored pilot questions look the sameReportedGateway Technical College, HESI A2 testing (questions and minutes per section)
Time	25 minutes on this section's own clockReportedGateway Technical College, HESI A2 testing (questions and minutes per section)
Even pace	About 50 seconds a question (25 × 60 ÷ 30)LifeScore
Scoring	Percent correct for the section, shown on your score report with a cumulative scoreReportedCentral Texas College, HESI A2 information sheet (on-screen calculator, score report)
Required?	Only if your program lists it: each program picks the sections and sets the minimumReportedChamberlain University, HESI Admission Assessment (A2) exam FAQs
In our full mock	6 questions in 6 minutes, the same pace on a shorter sectionLifeScore

Elsevier does not publish one public spec sheet for the HESI A2, so the question counts and times here are the ones schools publish for their own candidates, labelled Reported. On 20 October 2026 our build environment could not open Elsevier's or most schools' pages directly, so each was read through search-result text from the named page. Your program's own testing page always wins.

What does each HESI Biology topic ask?

Six topics carry most of the section; genetics and cell biology are the two worth the most study time.

The topics follow the chapters of Elsevier's Admission Assessment Exam Review. "What it covers" is the content; "how it reads" is our description of the questions you will meet, from writing and checking hundreds of them.

Biomolecules and water
What it covers: Carbohydrates, lipids, proteins and nucleic acids, their building blocks, and the properties of water.
How it reads: Which molecule is made of amino acids? Why does water resist temperature change?
Cells and organelles
What it covers: Organelles and their jobs, prokaryotes and eukaryotes, cell theory.
How it reads: Which organelle packages proteins? What do plant cells have that animal cells lack?
Membranes and transport
What it covers: Diffusion, osmosis, active transport, tonicity.
How it reads: What happens to a cell in a hypertonic solution?
Metabolism
What it covers: Enzymes, ATP, glycolysis, the Krebs cycle, the electron transport chain, fermentation and photosynthesis.
How it reads: Where does glycolysis happen? What are the reactants of photosynthesis?
Cell division and genetics
What it covers: Mitosis and meiosis, alleles, Punnett squares, incomplete dominance, codominance and sex-linked traits.
How it reads: Bb × Bb: what share of offspring show the recessive trait?
DNA and protein synthesis
What it covers: Base pairing, transcription, translation, codons and mutations.
How it reads: Write the mRNA codon for a DNA template strand.

What do HESI A2 Biology questions look like?

Three original questions: a monohybrid cross, an organelle question and a transcription question, each worked.

Try each one before you open the answer. They are original, written by us in the HESI A2 style, and are not real HESI items or questions from our mocks. The first is worked open.

HESI A2-style question 1 · Genetics
In pea plants, tall (T) is dominant over short (t). A Tt plant is crossed with a tt plant. What fraction of the offspring is expected to be short?
1. A0
2. B1/2
3. C1/4
4. D3/4
Worked answer
B: 1/2. The Punnett square gives Tt, Tt, tt, tt: two of four offspring are tt, so half are short.
1. Write the gametes: Tt gives T or t; tt gives only t.
2. Combine: Tt, Tt, tt, tt.
3. Short plants are tt: 2 of 4, or 1/2.
The trap: Using the 3:1 ratio from Tt × Tt, which gives 1/4 short. Check both parents before reaching for a ratio.
HESI A2-style question 2 · Cells
Which organelle would you expect to find in especially large numbers in a heart muscle cell, which uses a great deal of energy?
1. AVacuoles
2. BLysosomes
3. CMitochondria
4. DCentrioles
Show the worked answer
C: Mitochondria. Mitochondria make most of a cell's ATP by aerobic respiration, so energy-hungry cells such as heart muscle are packed with them.
1. Name the need: energy, which means ATP.
2. Name the organelle that makes most ATP: the mitochondrion.
3. More demand means more mitochondria.
The trap: Choosing ribosomes or lysosomes because muscle "builds" or "breaks down" protein. The clue is energy.
HESI A2-style question 3 · DNA
A DNA template strand reads 3'-GCA-5'. Which mRNA codon is transcribed from it?
1. A5'-CGU-3'
2. B5'-GCA-3'
3. C5'-CGT-3'
4. D5'-UGC-3'
Show the worked answer
A: 5'-CGU-3'. mRNA pairs with the template: G with C, C with G and A with U (RNA has uracil, not thymine), running 5' to 3': CGU.
1. Pair each base: G→C, C→G, A→U.
2. RNA uses U in place of T.
3. Write it antiparallel, 5' to 3': CGU.
The trap: Writing T instead of U, or copying the template instead of pairing it.

Make Biology a section you bank

Twelve questions show the gap. 4 more Biology drills and 8 full seven-section mocks close it.

The HESI A2 Pass Pack gives you 8 full mocks on the real clock, 28 drills of 12 questions for the sections that cost you points, and a predictor that turns your mocks into the odds of reaching your target. One payment, no subscription, and your free score stays free.

Prep courses for these tests usually cost $19 to $129. The HESI A2 Pass Pack is US$39 (£29), once.

See the HESI A2 Pass Pack How our questions are built and checked

8
timed mocks: 28
topic drills: 1
score predictor

Which biology processes should I know step by step?

These six. Each has a place, inputs, outputs and a favorite question.

Our summary of the processes HESI-style biology asks about most
Process	Where	In and out
Glycolysis	Cytoplasm	Glucose in; pyruvate and a little ATP out
Krebs cycle	Mitochondrial matrix	Pyruvate products in; carbon dioxide and electron carriers out
Electron transport chain	Inner mitochondrial membrane	Oxygen is the final electron acceptor; most ATP made here
Photosynthesis	Chloroplast	Carbon dioxide and water in; glucose and oxygen out
Transcription	Nucleus	DNA template in; mRNA out
Translation	Ribosome	mRNA and tRNA-carried amino acids in; protein out

Mitosis makes two identical cells with the full chromosome number; meiosis makes four different cells with half (23 in humans). Crossing over happens in prophase I of meiosis.

How should I pace the HESI Biology section?

Aim for about 50 seconds a question on average: faster on the questions you know, so the hard ones get the time they need. Use these checkpoints.

Our checkpoints, from the reported 30 questions in 25 minutes
When	Where you should be	What to do
6 minutes in	Question 8	On pace: keep going
13 minutes in	Question 15	Behind by 3 or more? Guess and move on from any question past a minute
19 minutes in	Question 23	Leave the last minutes for a guess on every blank

Most biology questions are recall and take 20 to 30 seconds. Genetics and transcription questions take longer; sketch the Punnett square or the base pairs rather than doing them in your head.

Leave no question blank: there is no penalty for a wrong answer on a percent-correct score.

A wrong answer and a blank both score zero on a percent-correct score, so never leave a question empty when the clock is about to run out.

What traps cost the most points on HESI Biology?

Biology misses cluster around a few confusions.

Using T instead of U when writing RNA.
Reaching for the 3:1 ratio without checking both parents' genotypes.
Mixing hypertonic and hypotonic: in a hypertonic solution the cell loses water and shrinks.
Confusing the independent variable (what the experimenter changes) with the dependent one (what is measured).

How should I study for HESI Biology?

Thirty minutes a day for a week, one topic a day, with genetics given two days.

Our plan, with minutes a day

Day 1
25 min
Take the free drill above. Sort misses by topic.
Day 2
30 min
Biomolecules and water.
Day 3
30 min
Cells, organelles and transport.
Day 4
30 min
Respiration and photosynthesis: learn the table above.
Day 5
30 min
Mitosis, meiosis and ten Punnett squares.
Day 6
30 min
DNA, transcription and translation; then a timed mixed set.
Day 7
20 min
Review only your misses.

How much does Biology count for nursing school admission?

Biology is required by some programs and not others; it is more common in RN and BSN programs than in practical nursing.

Check your program's list before studying biology at all. Where it is required it usually counts toward a science or cumulative score. See the HESI A2 passing score page for how programs combine sections.

Biology overlaps heavily with the TEAS science section; see the TEAS science practice test.

Scores reach your Evolve account within about 24 to 48 hours, with a percentage for each section and a cumulative score. Retake rules are set by each school. Baylor, for example, allows at most three attempts with 60 days between them.

Frequently asked questions

How many questions are on HESI A2 biology?

Schools list 30 questions in 25 minutes, with 25 scored.

What biology is on the HESI A2?

Biomolecules, cells and transport, metabolism, cell division, genetics, DNA and protein synthesis, and the scientific method.

Do I need to take HESI biology?

Only if your program requires it. The program chooses the sections, so check its admissions page.

Is the free biology drill the real HESI?

No. It is 12 original HESI A2-style questions at the real section pace. LifeScore is not affiliated with Elsevier.

All seven sections, on the real clocks

8 full HESI A2-style mocks, 28 section drills (4 for Biology) and every answer worked, in one payment with no subscription.