TEAS 7 science guide: every objective, how deep to study and practice questions
The TEAS 7 science section has 50 questions in 60 minutes. Of its 44 scored items, 18 cover human anatomy and physiology, the largest share, with 9 on biology, 8 on chemistry and 9 on scientific reasoning. Most scored science items fall outside A&P, so study all four areas at the depth shown below.
TEAS 7 science at a glance
50 questions in 60 minutes (about 1.2 minutes per question), the third section, after the optional break.
44 scored items and 6 unscored pretest items.
Human Anatomy and Physiology: 18 scored items, the largest share (about 41%).
Biology: 9. Chemistry: 8. Scientific Reasoning: 9. Together, 26 of the 44 scored items are outside A&P.
The built-in basic calculator is available in the science section too.
What science is on the TEAS 7? Every objective with depth labels
Depth labels are TEASPATH’s editorial judgment from the wording of ATI’s objectives and the book chapters. ATI does not publish how deeply each objective is tested.
S.1.1 Body orientation (Human Anatomy and Physiology): Use anatomical position, directional terms and body planes to read a body diagram. Must know: Anatomical position: standing, facing forward, arms at the sides, palms forward. Left and right mean the person’s left and right. Paired terms: superior/inferior, anterior (ventral)/posterior (dorsal), medial/lateral, proximal/distal (on limbs) and superficial/deep. Planes: sagittal (left and right parts), frontal or coronal (front and back), transverse (upper and lower). Know the basics: Major body cavities: cranial, thoracic, abdominal and pelvic. Body regions such as the four abdominal quadrants. Beyond the TEAS: Memorizing every surface landmark and regional term. Book chapter 27: Orient the body and explain its barrier.
S.1.2 Respiratory system (Human Anatomy and Physiology): Explain how air moves in and out and how oxygen and carbon dioxide are exchanged. Must know: Airflow: nose or mouth, pharynx, larynx, trachea, bronchi, bronchioles, alveoli. Inhaling: the diaphragm contracts and flattens, chest volume rises, pressure in the lungs falls and air flows in. Gas exchange happens by diffusion across the alveoli and capillaries: oxygen into the blood, carbon dioxide out. Know the basics: The epiglottis covers the airway during swallowing. Hemoglobin in red blood cells carries most of the oxygen in blood. The brainstem sets breathing rate, responding mainly to carbon dioxide levels. Beyond the TEAS: Lung-volume calculations and oxygen-hemoglobin dissociation curves. Book chapter 30: Link breathing with circulation.
S.1.3 Cardiovascular system (Human Anatomy and Physiology): Trace blood through the heart, lungs and body, and tell the heart’s electrical control apart from its pumping. Must know: The full route of blood through the four chambers and four valves (see the blood-flow list on this page). Arteries carry blood away from the heart and veins carry it toward the heart, whatever its oxygen level. The pulmonary artery carries oxygen-poor blood. Pulmonary circuit (right side to the lungs) and systemic circuit (left side to the body). The SA node is the natural pacemaker; the signal passes to the AV node, which briefly delays it, then into the ventricles. Know the basics: Blood components: red cells carry oxygen, white cells defend, platelets help clotting, plasma carries dissolved substances. Capillaries are where substances are exchanged with tissues. The left ventricle has the thickest wall because it pumps blood to the whole body. Beyond the TEAS: Interpreting ECG waveforms or calculating cardiac output. Book chapter 30: Link breathing with circulation.
S.1.4 Digestive system (Human Anatomy and Physiology): Separate the path food takes from the organs that add secretions, and explain where nutrients are absorbed. Must know: Food route: mouth, pharynx, esophagus, stomach, small intestine, large intestine, rectum, anus. Accessory organs add secretions but food does not pass through them: the liver makes bile, the gallbladder stores it, the pancreas releases digestive enzymes. Most nutrients are absorbed in the small intestine, whose villi increase surface area; the large intestine absorbs much of the remaining water. Know the basics: Mechanical digestion (chewing, churning) versus chemical digestion (enzymes). Examples of enzymes: amylase starts starch digestion in the mouth, pepsin digests protein in the stomach, lipase digests fats. Peristalsis is the wave of muscle contraction that moves food along. Beyond the TEAS: Detailed hormonal control of digestion and every enzyme’s substrate. Book chapter 31: Move nutrients and regulate water.
S.1.5 Nervous system (Human Anatomy and Physiology): Tell the central and peripheral nervous systems apart and follow the direction information travels. Must know: Central nervous system (CNS): brain and spinal cord. Peripheral nervous system (PNS): nerves outside them. Afferent (sensory) neurons carry signals toward the CNS; efferent (motor) neurons carry signals away to muscles and glands. Somatic (voluntary) versus autonomic (involuntary) control; sympathetic is “fight or flight,” parasympathetic is “rest and digest.” Know the basics: Neuron parts: dendrites receive, the cell body processes, the axon sends; neurotransmitters cross the synapse. Brain regions: cerebrum (thinking, voluntary movement), cerebellum (balance and coordination), brainstem (breathing and heart rate). A reflex arc can respond before the brain is involved. Beyond the TEAS: Ion-channel details of the action potential and the names of all cranial nerves. Book chapter 29: Coordinate responses through nerves and hormones.
S.1.6 Muscular system (Human Anatomy and Physiology): Match each muscle type to where it is and what it does, and explain basic contraction. Must know: Skeletal muscle: voluntary, striated, attached to bones. Cardiac muscle: involuntary, striated, only in the heart. Smooth muscle: involuntary, not striated, in the walls of hollow organs and blood vessels. Contraction: actin and myosin filaments slide past each other, which needs calcium and ATP. Know the basics: Tendons connect muscle to bone; ligaments connect bone to bone. Muscles only pull, so they work in opposing pairs such as the biceps and triceps. Beyond the TEAS: Naming every band of the sarcomere or every individual muscle. Book chapter 28: Connect support, movement and muscle.
S.1.7 Reproductive system (Human Anatomy and Physiology): Connect reproductive organs with the gametes and hormones they produce and the main events of reproduction. Must know: The testes make sperm and testosterone; sperm mature in the epididymis and travel through the vas deferens to the urethra. The ovaries release eggs and make estrogen and progesterone; fertilization usually happens in the uterine (fallopian) tube and implantation in the uterus. Gametes are haploid cells made by meiosis. FSH and LH from the anterior pituitary regulate the ovaries and testes; an LH surge triggers ovulation. Know the basics: Accessory glands such as the seminal vesicles and prostate add fluid to semen. The phases of a model 28-day menstrual cycle and the role of the placenta. Beyond the TEAS: Detailed stages of embryonic development. Book chapter 33: Connect reproductive structures, cells and regulation.
S.1.8 Integumentary system (skin) (Human Anatomy and Physiology): Tell the skin layers apart and explain how skin protects, senses and controls temperature. Must know: Epidermis: outer layer, no blood vessels, keratin for protection and melanin for pigment. Dermis: blood vessels, nerves, glands and hair follicles. Hypodermis (subcutaneous layer): fat for insulation and cushioning. Functions: barrier against water loss and microbes, sensation, temperature control and vitamin D synthesis. Cooling: sweat evaporates and skin blood vessels widen. Conserving heat: skin blood vessels narrow. Know the basics: New epidermal cells form in the deepest layer; the outermost layer is dead, keratin-filled cells. Sweat glands help cool the body; sebaceous (oil) glands keep skin and hair supple. Beyond the TEAS: Clinical skin disorders and burn treatment. Book chapter 27: Orient the body and explain its barrier.
S.1.9 Endocrine system (Human Anatomy and Physiology): Use target cells and feedback loops to explain how hormones work. Must know: Hormones travel in the blood but act only on cells with matching receptors. Negative feedback reverses a change and is the most common control loop. Insulin (pancreatic beta cells) lowers blood glucose; glucagon (alpha cells) raises it. Key sources: pituitary (growth hormone, TSH, ACTH, FSH, LH, prolactin; ADH and oxytocin are released from the posterior pituitary), thyroid (T3 and T4 for metabolism), parathyroids (PTH raises blood calcium), adrenals (cortisol, aldosterone, epinephrine). Know the basics: Positive feedback amplifies a change, as oxytocin does during labor. The hypothalamus links the nervous and endocrine systems by controlling the pituitary. The pineal gland makes melatonin for daily rhythms. Beyond the TEAS: Second-messenger signalling cascades inside target cells. Book chapter 29: Coordinate responses through nerves and hormones.
S.1.10 Urinary system (Human Anatomy and Physiology): Tell filtration, reabsorption and secretion apart and follow urine out of the body. Must know: The nephron is the kidney’s working unit. Filtration: blood is filtered at the glomerulus. Reabsorption: water, glucose and salts return to the blood. Secretion: extra wastes move into the tubule. Urine route: kidney, ureter, bladder, urethra. ADH increases water reabsorption, making urine more concentrated. Know the basics: Nephron parts in order: glomerulus and Bowman’s capsule, proximal tubule, loop of Henle, distal tubule, collecting duct. Aldosterone increases sodium reabsorption; the kidneys also help control blood pressure and pH. Beyond the TEAS: Calculating filtration rate or clearance. Book chapter 31: Move nutrients and regulate water.
S.1.11 Immune system (Human Anatomy and Physiology): Tell general barriers apart from specific responses, and active immunity from passive immunity. Must know: Innate defenses are fast and general: skin, mucous membranes, phagocytes, inflammation and fever. Adaptive defenses are specific and have memory: B cells make antibodies; helper T cells coordinate; cytotoxic T cells destroy infected cells. Active immunity: your body makes its own antibodies (after infection or a vaccine) and it lasts. Passive immunity: you receive antibodies (across the placenta, in breast milk or by injection) and it is short-lived. Know the basics: An antigen is a molecule the immune system recognizes as foreign. Lymphatic organs: lymph nodes filter lymph, the spleen filters blood, the thymus is where T cells mature, red bone marrow makes blood cells. Beyond the TEAS: The complement cascade and MHC molecule details. Book chapter 32: Explain layered immune protection.
S.1.12 Skeletal system (Human Anatomy and Physiology): Explain what bones do and which cells build and remodel them. Must know: Functions: support, protection, movement with muscles, mineral (calcium) storage and blood cell production in red marrow. Remodeling: osteoblasts build bone, osteoclasts break it down, osteocytes maintain it. Compact bone is dense and forms the outer layer; spongy bone is lighter and holds red marrow. Know the basics: Axial skeleton (skull, vertebral column, ribs, sternum) versus appendicular skeleton (limbs and the girdles that attach them). Joint types such as hinge (elbow, knee) and ball-and-socket (shoulder, hip); a typical adult has 206 bones. Beyond the TEAS: Memorizing every bone and bone marking. Book chapter 28: Connect support, movement and muscle.
S.2.1 Cells and organization (Biology): Work out which cell structure does a job and put levels of organization in order. Must know: Nucleus: holds DNA. Ribosomes: make proteins. Mitochondria: release energy as ATP. Golgi apparatus: modifies and packages proteins. Rough ER: processes proteins; smooth ER: makes lipids. Lysosomes: break down waste. Cell membrane: controls what enters and leaves. Plant cells also have a cell wall, chloroplasts and a large central vacuole, and they still have mitochondria. Prokaryotes (bacteria) have no nucleus but do have ribosomes. Levels: cell, tissue, organ, organ system, organism. Diffusion and osmosis move substances down a concentration gradient without energy; active transport uses energy to move them against it. Know the basics: Mitosis makes two identical diploid cells for growth and repair; meiosis makes four genetically different haploid gametes. The phases of mitosis: prophase, metaphase, anaphase, telophase. Beyond the TEAS: The detailed steps of the Krebs cycle and electron transport chain. Book chapter 23: Connect molecules, membranes and cells.
S.2.2 From gene to protein (Biology): Follow genetic information from DNA to mRNA to a chain of amino acids. Must know: Transcription copies a gene’s DNA into mRNA (in the nucleus in human cells); translation at the ribosome uses the mRNA to build a protein. Base pairing: in DNA, A pairs with T and C with G. RNA uses uracil (U) instead of thymine, so a DNA A pairs with an RNA U. A codon is three mRNA bases that code for one amino acid or a stop signal; tRNA carries the matching amino acid using its anticodon. Know the basics: DNA is a double helix of nucleotides (sugar, phosphate and base). A substitution changes one base; an insertion or deletion can shift the reading frame and change every codon after it. Beyond the TEAS: Memorizing which codon codes for which amino acid. Book chapter 24: Follow genetic information to a protein.
S.2.3 Inheritance (Biology): Use a Punnett square to work out the chances of each outcome under a simple Mendelian model. Must know: Alleles are versions of a gene. Genotype is the allele pair (Pp); phenotype is the observable trait. Homozygous means two identical alleles (PP or pp); heterozygous means two different alleles (Pp). A dominant allele shows when present; a recessive trait shows only with two recessive alleles. Pp × Pp gives 1 PP : 2 Pp : 1 pp, so a 3:1 ratio of dominant to recessive phenotypes. Each offspring has the same chance; it is not a quota. Know the basics: A two-trait cross of two heterozygotes for unlinked genes gives a 9:3:3:1 phenotype ratio. Mendel’s laws of segregation and independent assortment. Beyond the TEAS: Linked genes, recombination frequencies and population genetics. Book chapter 25: Reason with an inheritance model.
S.2.4 Macromolecules (Biology): Relate the four major groups of biological molecules to their building blocks and jobs. Must know: Carbohydrates (sugars such as glucose; starch, glycogen, cellulose): quick energy and structure. Lipids (fats, phospholipids, steroids): long-term energy storage, membranes and some hormones. Proteins (chains of amino acids): enzymes, structure, transport and signalling. Nucleic acids (DNA and RNA, made of nucleotides): store and transmit genetic information. Enzymes are proteins that speed up reactions; heat or extreme pH can change their shape (denature them) and stop them working. Know the basics: Dehydration synthesis joins monomers into polymers; hydrolysis splits them with water. Beyond the TEAS: Drawing structural formulas of specific molecules. Book chapter 23: Connect molecules, membranes and cells.
S.2.5 Microorganisms (Biology): Tell the main kinds of microbes apart and explain how they can help or harm. Must know: Bacteria are single-celled prokaryotes with no nucleus. Viruses are not cells; they reproduce only inside a host cell, and antibiotics do not work against them. Fungi (yeasts and molds) and protozoa are eukaryotes. Many microbes are helpful (gut bacteria, decomposers, fermentation); pathogens cause disease. Know the basics: Common bacterial shapes: cocci (spheres), bacilli (rods), spirilla (spirals). Antibiotic resistance spreads when resistant bacteria survive treatment and multiply. Beyond the TEAS: Naming specific pathogens and the diseases each one causes. Book chapter 26: Distinguish microbes and their roles.
S.3.1 Atoms, isotopes and ions (Chemistry): Use counts of protons, neutrons and electrons to identify an element, an isotope or an ion. Must know: Protons (+) and neutrons (no charge) are in the nucleus; electrons (−) are outside it. Atomic number = number of protons, and it identifies the element. Mass number = protons + neutrons. Isotopes are atoms of the same element with different numbers of neutrons. Ions have gained or lost electrons: losing electrons makes a positive ion, gaining makes a negative ion. Know the basics: Periodic table: rows are periods; columns are groups with similar properties; metals are on the left. Ionic bonds transfer electrons; covalent bonds share them. Beyond the TEAS: Electron configuration notation and quantum numbers. Book chapter 20: Use an atomic model to explain matter.
S.3.2 Properties and states of matter (Chemistry): Tell a change of state apart from a change that makes a new substance. Must know: States: solid, liquid, gas. Melting, freezing, evaporation, condensation, sublimation and deposition are physical changes; the substance stays the same. A chemical change makes a new substance. Gas, color change, temperature change or a precipitate are clues, but none proves it alone. Know the basics: Density = mass ÷ volume. Ice is less dense than liquid water, so it floats. Adding heat speeds particle motion; during a phase change the temperature stays constant. Beyond the TEAS: Reading phase diagrams with triple and critical points. Book chapter 20: Use an atomic model to explain matter.
S.3.3 Chemical reactions (Chemistry): Count atoms to read and balance an ordinary chemical equation. Must know: Reactants are on the left of the arrow and products on the right. Mass is conserved, so each element has the same number of atoms on both sides. Balance with coefficients (the large numbers in front); never change subscripts, because that changes the substance. Atom count = coefficient × subscript. In 2H₂O there are 4 hydrogen atoms and 2 oxygen atoms. Know the basics: Reaction types: synthesis, decomposition, single replacement, double replacement, combustion. Exothermic reactions release energy; endothermic reactions absorb it. Beyond the TEAS: Multi-step stoichiometry with molar masses (gram-to-mole-to-gram calculations). Book chapter 21: Account for a reaction and its rate.
S.3.4 Reaction rates (Chemistry): Predict how conditions change how fast a reaction goes and judge whether a comparison is fair. Must know: Particles must collide with enough energy to react (collision theory). Rate usually rises with higher temperature, higher concentration, more surface area (smaller pieces) or a catalyst. A catalyst speeds a reaction by lowering the activation energy and is not used up. Enzymes are biological catalysts. A fair comparison changes only one condition at a time. Know the basics: Rate (how fast) is different from yield (how much product forms). Beyond the TEAS: Rate laws and reaction orders. Book chapter 21: Account for a reaction and its rate.
S.3.5 Solutions (Chemistry): Compare concentration and solubility using the units and conditions given. Must know: A solute dissolves in a solvent to make a solution; water is the most common solvent in the body. Concentration is the amount of solute per volume of solution. Diluting adds solvent and keeps the same amount of solute, so C₁V₁ = C₂V₂. Most solids dissolve better in warmer water; gases dissolve less in warmer water. Stirring speeds dissolving but does not change how much can dissolve. Know the basics: Unsaturated, saturated and supersaturated solutions. Osmosis: water moves toward the side with the higher solute concentration (hypertonic, hypotonic and isotonic solutions). Beyond the TEAS: Molality and colligative-property calculations. Book chapter 22: Explain solutions and introductory pH.
S.3.6 Acids, bases and pH (Chemistry): Compare acidity with the pH scale and explain neutralization. Must know: pH runs from 0 to 14: below 7 is acidic, 7 is neutral (pure water at 25 °C), above 7 is basic. Each whole pH unit is a tenfold change in hydrogen-ion concentration, so pH 3 has 100 times the hydrogen ions of pH 5. Acids release hydrogen ions (H⁺) in water; bases accept them or release hydroxide ions (OH⁻). Neutralization: an acid and a base react to form water and a salt. Know the basics: Normal blood pH is slightly basic, about 7.35 to 7.45, held steady by buffers. Stomach acid is strongly acidic. Beyond the TEAS: Calculating pH from a concentration with logarithms. Book chapter 22: Explain solutions and introductory pH.
S.4.1 Measurement (Scientific Reasoning): Choose suitable units and tools, and read a measurement with the right precision. Must know: SI base units: meter (length), kilogram (mass), second (time); liters for volume and degrees Celsius for everyday temperatures. Tools: a balance measures mass, a graduated cylinder measures liquid volume, a thermometer measures temperature, a ruler measures length. Read a water-based liquid’s volume at the bottom of its curved surface (the meniscus), with your eye level with it. Accuracy is closeness to the true value; precision is how close repeated measurements are to each other. Know the basics: Record one estimated digit beyond the smallest marked division. Scientific notation for very large and very small numbers. Beyond the TEAS: Formal error propagation. Book chapter 19: Investigate a question with evidence.
S.4.2 Evidence and logic (Scientific Reasoning): Pick the explanation the evidence supports best, and consider alternatives. Must know: A hypothesis is a testable, falsifiable prediction. Choose the conclusion that the data actually support; do not add claims the data cannot show. Correlation does not prove causation; look for other explanations. Know the basics: Deductive reasoning goes from a general rule to a specific case; inductive reasoning goes from specific observations to a general pattern. A theory is a well-tested explanation; a law describes a consistent pattern. Beyond the TEAS: Formal logic notation. Book chapter 19: Investigate a question with evidence.
S.4.3 Relationships in data (Scientific Reasoning): Read trends in tables and graphs and keep predictions within the evidence. Must know: Describe trends as increasing, decreasing or no clear pattern, using the axis labels and units. Interpolating (estimating between measured points) is safer than extrapolating beyond them. In a direct relationship both variables rise together; in an inverse relationship one rises as the other falls. Know the basics: A line of best fit summarizes a trend; outliers are points far from the rest. Beyond the TEAS: Regression statistics and correlation coefficients. Book chapter 19: Investigate a question with evidence.
S.4.4 Designing investigations (Scientific Reasoning): Identify variables and controls, and suggest changes that make an investigation fairer. Must know: Independent variable: what the investigator changes on purpose. Dependent variable: what is measured in response. Controlled variables are kept the same; a control group gets no treatment or the standard condition for comparison. A fair test changes one variable at a time; more trials and larger samples make results more reliable. Know the basics: The usual steps: question, hypothesis, experiment, data analysis, conclusion. Random assignment and blinding reduce bias. Beyond the TEAS: Statistical significance tests. Book chapter 19: Investigate a question with evidence.
Which body systems are on the TEAS?
Integumentary. Organs: Skin, hair, nails, sweat and oil glands. Functions: Barrier, temperature control, sensation, vitamin D synthesis. Know: Epidermis, dermis and hypodermis; sweat evaporation cools the body; melanin protects against UV light.
Skeletal. Organs: Bones, cartilage, ligaments, joints. Functions: Support, protection, movement, calcium storage, blood cell production. Know: Osteoblasts build bone and osteoclasts break it down; red marrow makes blood cells; ligaments join bone to bone.
Muscular. Organs: Skeletal, cardiac and smooth muscle; tendons. Functions: Movement, posture, heat production, moving material through hollow organs. Know: Three muscle types; actin and myosin slide using calcium and ATP; tendons join muscle to bone.
Nervous. Organs: Brain, spinal cord, nerves, sense organs. Functions: Fast electrical and chemical signalling. Know: CNS versus PNS; afferent signals travel in, efferent signals travel out; sympathetic versus parasympathetic.
Endocrine. Organs: Hypothalamus, pituitary, thyroid, parathyroids, adrenals, pancreas, gonads, pineal. Functions: Slower, longer-lasting control through hormones in the blood. Know: Hormones act only on cells with receptors; negative feedback; insulin lowers blood glucose and glucagon raises it.
Cardiovascular. Organs: Heart, arteries, veins, capillaries, blood. Functions: Transports oxygen, nutrients, hormones and wastes. Know: The route through the heart; arteries carry blood away from the heart; capillaries are the exchange sites; the SA node sets the pace.
Respiratory. Organs: Nose, pharynx, larynx, trachea, bronchi, lungs (alveoli), diaphragm. Functions: Gas exchange; helps regulate blood pH. Know: The diaphragm contracts to inhale; oxygen and carbon dioxide diffuse across the alveoli.
Digestive. Organs: Mouth, esophagus, stomach, small and large intestines; liver, gallbladder, pancreas. Functions: Breaks down food, absorbs nutrients, eliminates waste. Know: The small intestine absorbs most nutrients; the large intestine absorbs water; bile from the liver emulsifies fats.
Immune and lymphatic. Organs: White blood cells, lymph nodes and vessels, spleen, thymus, red bone marrow. Functions: Defends against pathogens; returns tissue fluid to the blood. Know: Innate versus adaptive defenses; B cells make antibodies; active versus passive immunity.
Reproductive. Organs: Testes, ovaries, uterine tubes, uterus, accessory glands. Functions: Makes gametes and sex hormones; supports pregnancy. Know: Meiosis makes haploid gametes; fertilization usually happens in the uterine tube; FSH and LH regulate the gonads.
What is the order of blood flow through the heart?
Oxygen-poor blood returns from the body through the superior and inferior venae cavae
Right atrium
Tricuspid valve
Right ventricle
Pulmonary valve
Pulmonary trunk and pulmonary arteries (oxygen-poor blood, away from the heart)
Lung capillaries: blood picks up oxygen and releases carbon dioxide
Pulmonary veins (oxygen-rich blood, toward the heart)
Left atrium
Mitral (bicuspid) valve
Left ventricle
Aortic valve
Aorta, then systemic arteries to the body’s capillaries
Science topics that surprise students
Chemistry: Students who mostly drilled anatomy often say chemistry questions caught them off guard. Chemistry is 8 scored items, close to Biology’s 9. Atomic number = protons; mass number = protons + neutrons; charge = protons − electrons. Isotopes differ in neutrons; ions differ in electrons. Balance equations with coefficients, never subscripts. Heat, concentration, surface area and catalysts usually speed reactions. Each pH unit is a tenfold change; lower pH means more hydrogen ions.
DNA, RNA and protein synthesis: Transcription and translation questions are a surprise students mention repeatedly. DNA → mRNA is transcription; mRNA → protein is translation, at the ribosome. DNA pairs A–T and C–G; RNA replaces T with U. Template DNA TAC becomes mRNA AUG. Three mRNA bases form one codon for one amino acid or a stop signal.
Genetics and Punnett squares: Students report genetics items alongside DNA questions, usually as probability problems. Write each parent’s two alleles on the sides of the square. Count Pp and pP as the same genotype. Pp × Pp: 1/4 PP, 1/2 Pp, 1/4 pp; 3/4 show the dominant trait. Pp × pp: half heterozygous, half homozygous recessive.
Independent and dependent variables: Scientific reasoning is 9 scored items, as many as Biology, and variable questions trip up students who studied only content. Independent: what you change on purpose (often on the x-axis). Dependent: what you measure (often on the y-axis). Controlled: everything you keep the same. A control group gives a baseline for comparison.
How to study for the TEAS science section
Take a short mixed diagnostic first so you know which of the four areas needs the most time.
Give A&P the most hours because it is the largest share (18 of 44 scored items), but schedule chemistry, biology and scientific reasoning every week: together they are 26 of the 44.
Learn pathways as sequences you can recite without looking: blood through the heart, air into the alveoli, food through the gut, urine formation.
Use hormone tables (gland, hormone, target, effect) and close the page to recall them. Practice testing is rated a high-utility study technique in a major review of learning research.
If you have not taken A&P or chemistry recently, start earlier: students without recent coursework report the biggest science gaps.
Spread science across the whole study period instead of cramming it into one week; spaced practice is also rated high utility.
Sample TEAS science questions (original)
Blood has just been pumped out of the right ventricle. Where does it go next? Answer: D. The pulmonary trunk and arteries The right ventricle pumps oxygen-poor blood through the pulmonary valve into the pulmonary trunk, which branches into the pulmonary arteries to the lungs. The aorta leaves the left ventricle, and the left atrium receives blood from the pulmonary veins.
Which vessel carries oxygen-poor blood away from the heart? Answer: C. Pulmonary artery Arteries are defined by direction: they carry blood away from the heart. The pulmonary artery carries oxygen-poor blood from the right ventricle to the lungs. The pulmonary vein carries oxygen-rich blood back toward the heart.
Blood glucose rises after a meal. Which response helps return it toward normal? Answer: A. Beta cells in the pancreas release insulin, which helps cells take up glucose. Insulin from pancreatic beta cells promotes glucose uptake and storage, lowering blood glucose: a negative feedback response. Glucagon (alpha cells) raises blood glucose, aldosterone affects sodium and PTH raises blood calcium.
A section of a DNA template strand reads TAC GGA. Which mRNA sequence is transcribed from it? Answer: B. AUG CCU Pair each DNA base with its RNA partner: T→A, A→U, C→G, G→C. TAC becomes AUG and GGA becomes CCU. Choice A pairs correctly but uses T, which RNA does not contain.
In a plant, purple flowers (P) are dominant to white flowers (p). Two Pp plants are crossed. What is the probability that an offspring has white flowers? Answer: D. 25% The Punnett square for Pp × Pp gives PP, Pp, Pp and pp. Only pp (1 of 4) shows the recessive white color, so the probability is 1/4, or 25%. The chance applies to each offspring separately.
An atom has 17 protons, 18 neutrons and 18 electrons. Which description is correct? Answer: C. An ion with a −1 charge and mass number 35 Mass number = protons + neutrons = 17 + 18 = 35. Charge = protons − electrons = 17 − 18 = −1, so it is a negative ion. Electrons do not count toward mass number, which rules out D.
Solution X has a pH of 3 and solution Y has a pH of 5. Which statement is correct? Answer: A. X has 100 times the hydrogen-ion concentration of Y. Each whole pH unit is a tenfold change. X is 2 units lower, so it has 10 × 10 = 100 times the hydrogen-ion concentration and is the more acidic solution. Both solutions are below 7, so both are acidic.
A student grows bean plants under 4, 8 or 12 hours of light a day for three weeks. Every plant gets the same water, soil and pot size, and the student measures each plant’s height. What is the dependent variable? Answer: A. Plant height The dependent variable is what is measured in response: plant height. Hours of light is the independent variable the student changes on purpose; water, soil and pot size are controlled variables.
In the same bean-plant investigation, which are controlled variables? I. Amount of water II. Soil type III. Hours of light IV. Pot size Answer: B. I, II and IV only Controlled variables are kept the same for every group: water, soil and pot size. Hours of light changes on purpose, so it is the independent variable, not a controlled one.
A breastfed infant receives antibodies from the mother’s milk. What type of immunity is this? Answer: C. Natural passive immunity The infant receives ready-made antibodies rather than making them, so the immunity is passive, and it comes through a natural route, so it is natural passive immunity. It is short-lived because the infant’s body did not make the antibodies.
Questions and answers
What science topics are on the TEAS 7? The science section has 50 questions in 60 minutes; 44 are scored. ATI lists 18 scored items in human anatomy and physiology, 9 in biology, 8 in chemistry and 9 in scientific reasoning, spread across 27 objectives from body systems and cells to atoms, pH and experimental design.
Is the TEAS science section hard? ATI does not publish section difficulty. In public forum posts we reviewed, science was the section students most often called their hardest or lowest, usually because of its breadth: chemistry, DNA and RNA, genetics and variables questions surprised students who studied mainly anatomy.
How deep should I study anatomy and physiology for the TEAS? Aim for pathways, functions and cause and effect rather than exhaustive naming: blood flow through the heart, where each major hormone comes from and what it does, how the nephron forms urine, and active versus passive immunity. The depth labels on this page show what to know first.
What chemistry is on the TEAS 7? Six objectives: atomic structure, isotopes and ions; states of matter and physical versus chemical change; balancing equations; reaction rates; solutions and concentration; and acids, bases and pH. ATI lists 8 scored chemistry items.
What do TEAS scientific reasoning questions look like? They describe an investigation, measurement or data set and ask you to identify the independent and dependent variables, choose a suitable tool or unit, read a trend, or pick the conclusion the evidence supports. ATI lists 9 scored items, as many as biology.
What should I study first for TEAS science? Start with a diagnostic, then give anatomy and physiology the most time because it is the largest share. Do not leave chemistry, biology and scientific reasoning for last: together they are 26 of the 44 scored science items.
Can I use a calculator in the TEAS science section? Yes. ATI says the built-in basic calculator is available on every question in every section, not just math. It helps with density, dilution and data questions.
Is there a free TEAS science study guide? This page, the free TEASPATH science labs and the free practice preview are free. ATI also offers a free online practice test with 60 questions, 15 per section. The TEASPATH book covers every science objective in 15 chapters.
TEASPATH is independent of ATI. ATI TEAS® and TEAS® are registered trademarks of Assessment Technologies Institute, L.L.C., which is not affiliated with and does not endorse TEASPATH. Practice results are not official scores or admission predictions.