TEAS Science · 90 questions · Page 1 of 9

90 Free TEAS Science Practice Questions with Answers

90 original TEAS 7-style science practice questions, each with a full rationale, distractor analysis, and study tips. Use these to drill the exact concepts the ATI TEAS tests — then jump into a timed quiz when you're ready.

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TEAS Science study question hub

Build connections across anatomy and physiology, biology, chemistry, and scientific reasoning. The strongest preparation combines factual recall with questions that ask you to predict, compare, interpret data, and apply a scientific principle.

Human anatomy and physiology

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Cell biology and genetics

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Chemistry and matter

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Experiments, variables, and data

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Browse 85 covered topics

Acid-base chemistry (1)Atomic Structure and Bonding (1)Biochemical Structures (1)Biological Macromolecules (1)Blood (1)Blood components (1)Body cavities (1)Cardiovascular system (1)Cell Biology Basics (2)Cell membrane transport (1)Cellular Biology & Enzymes (1)Cellular Biology and Organelles (1)Cellular Biology and Specialization (1)Cellular Biology Structure (1)Cellular Energy Processes (1)Cellular respiration (1)Cellular Transport Mechanisms (1)Chemical bonds (1)Digestive system (1)DNA and RNA (1)DNA Laboratory Techniques (1)DNA Structure and Replication (1)Ecology (1)Endocrine system (1)Endocrine System and Calcium Regulation (1)Endocrine System Regulation (1)Enzymes (1)Experimental controls (1)Experimental design (1)Female Reproductive System (1)Genetics (1)Genetics and Heredity (1)Genetics and Inheritance (1)Heart Anatomy and Histology (1)Homeostasis (1)Hormone regulation (1)Immune system (1)Immune System and Blood Components (1)Inheritance (1)Integumentary system (1)Integumentary System Biology (1)Integumentary System Excretion (2)Integumentary System Structure (1)Lymphatic system (1)Macromolecules (1)Macromolecules and Growth (1)Macromolecules and Lipids (1)Macromolecules and Nucleic Acids (1)Matter (1)Measurement and Data (1)Mendelian Genetics Concepts (1)Microbiology Classifications (1)Mitosis (1)Molecular Biology & Genetics (1)Molecular Genetics and Transcription (1)Muscular system (1)Muscular System Histology (1)Muscular System Physiology (1)Nervous system (1)Nervous System Communication (1)Nervous System Functions (1)Nucleotide Structure and Genetics (1)Phase Changes and Equilibrium fluid dynamics (1)Population Dynamics (1)Population ecology (1)Protein synthesis (1)Reaction rates (1)Renal system (1)Reproductive system (1)Respiratory mechanics (1)Respiratory system (1)Respiratory System Anatomy (2)Respiratory System Function (1)Respiratory System Gas Exchange (2)Scientific graphs (1)Scientific measurement (1)Scientific Method and Hypothesis (1)Scientific reasoning (1)Scientific Reasoning and Bias (1)Scientific Reasoning and Data Interpretation (2)Scientific Reasoning and Hypotheses (1)Skeletal system (1)Special Senses: Visual System (1)States of matter (1)Stoichiometry (1)

TEAS Science Questions, Answers, and Rationales

Open any question to check the correct answer and a concise explanation. Each question also links to a dedicated study page with a full rationale and study tip.

Phase Changes and Equilibrium fluid dynamics

In a sealed, airtight container partially filled with water at a constant temperature, which of the following best describes the state of dynamic equilibrium between the liquid and gas phases?

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Answer: B. Evaporation will occur until the rate of molecules escaping the liquid equals the rate of molecules returning to the liquid.

In a closed system, equilibrium is reached when the rate of evaporation equals the rate of condensation, maintaining constant levels of each phase.

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Nervous System Functions

Which of the following best describes the primary role of an efferent (motor) neuron in the human nervous system?

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Answer: B. Transmitting signals from the spinal cord to an effector, such as a muscle or gland

Motor (efferent) neurons carry impulses away from the central nervous system to muscles or glands to trigger a response.

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Integumentary System Excretion

The human body utilizes sweat glands to assist in thermoregulation and the excretion of metabolic wastes. Which of the following nitrogenous waste products is commonly found in sweat as a byproduct of protein catabolism?

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Answer: C. Urea

Urea is a nitrogenous waste product formed from protein breakdown that is excreted in small amounts through sweat glands.

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Macromolecules and Growth

A patient recovering from surgery is prescribed a diet high in essential amino acids to accelerate the healing process. Which of the following best describes the physiological role these amino acids play in rebuilding damaged tissue?

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Answer: A. Synthesize cellular proteins for tissue repair and development

Amino acids are the building blocks of proteins, which are essential for structural repair, enzyme production, and tissue growth in the body.

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Scientific Reasoning and Hypotheses

Historically, parasitic worm infestations have been classified strictly as harmful to human health. However, recent clinical studies suggest that these infestations may actually dampen overactive immune responses in patients with Crohn's disease. Based on this new evidence, how should the initial hypothesis regarding parasitic worms be revised?

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Answer: B. Worm infestation can have both detrimental and therapeutic effects on a host.

When new data contradicts an old hypothesis, the hypothesis must be revised to include the new findings. Choice B reflects both the harm and the help.

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Cellular Energy Processes

During which of the following cellular processes is solar energy converted into chemical energy and stored within the bonds of glucose?

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Answer: C. Photosynthesis

Photosynthesis is the process that converts solar energy into chemical energy, storing it in the bonds of glucose for later use by the cell.

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Scientific Reasoning and Data Interpretation

A researcher is testing the effects of pH levels on the catalytic activity of a specific digestive enzyme. Three test tubes containing identical concentrations of the enzyme and substrate are maintained at $37^\circ\text{C}$ but set to different pH levels: pH 3.0, pH 5.0, and pH 7.0. After 30 minutes, the amount of product formed is measured. The results show that the pH 5.0 group produced 45 mg of product, the pH 3.0 group produced 15 mg, and the pH 7.0 group produced 22 mg. Which of the following conclusions is best supported by these data?

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Answer: D. Optimal enzyme activity is achieved at pH 5.0 compared to the other tested levels.

Identify the optimal pH for enzyme activity by comparing the quantitative results of three different experimental groups.

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Respiratory System Anatomy

Oxygen and carbon dioxide are exchanged between the external environment and the blood through the thin walls of which respiratory structure?

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Answer: B. Alveoli

The alveoli are the primary site of gas exchange in the lungs, featuring thin walls that allow oxygen and CO2 to diffuse into and out of the blood.

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Heart Anatomy and Histology

A student is examining a histological slide of the heart and observes a layer of smooth, thin epithelial tissue that is in direct contact with the blood within the ventricles. Which of the following layers is the student viewing?

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Answer: C. Endocardium

The endocardium is the innermost layer of the heart, consisting of smooth epithelial tissue that directly contacts the blood in the chambers.

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#10

Macromolecules and Lipids

Which of the following best describes the structural difference between saturated and unsaturated fatty acids?

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Answer: C. Saturated fats lack double bonds between carbon atoms, allowing them to pack tightly and remain solid at room temperature.

Saturated fats have no double bonds and are solid at room temp; unsaturated fats have double bonds that create kinks, making them liquid.

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Study TEAS Science in depth

Use these focused guides to review the concepts behind the questions, then return to this bank for more practice.

TEAS Science Practice Guide

Review anatomy, biology, chemistry, and scientific reasoning.

Anatomy & Physiology Practice Test

Practice body-system questions with detailed rationales.

TEAS Science Flashcards

Strengthen recall across major science concepts.

TEAS Science Cheat Sheet

Review high-yield science facts and relationships.

TEAS Science Practice Questions: FAQ

What science topics should I practice for the TEAS?

Review human anatomy and physiology, biology, chemistry, and scientific reasoning, including experiments, variables, measurements, and interpreting evidence.

How can I study effectively for TEAS Science questions?

Group practice by topic, review the rationale after every answer, and connect facts to processes such as body-system functions or cause-and-effect relationships in experiments.

Do these TEAS Science practice questions have rationales?

Yes. Each question includes the correct answer and rationale, with a separate explanation page for additional detail and a focused study tip.

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