TEAS Science Study Guide

The TEAS Science section consists of 50 questions (44 scored) completed in 60 minutes, representing 29% of your total exam score. This comprehensive guide covers all four essential areas you need to master for success on the ATI TEAS Version 7 exam.

Section Breakdown:

• Human Anatomy & Physiology: 18 questions (12%)
• Biology: 9 questions (6%)
• Chemistry: 8 questions (5%)
• Scientific Reasoning: 9 questions (6%)

Human Anatomy & Physiology (18 Questions)

Circulatory System

Heart Structure and Function The human heart is a four-chambered muscular organ consisting of two atria (upper chambers) and two ventricles (lower chambers). The right atrium receives deoxygenated blood from the body through the superior and inferior vena cava. Blood then flows to the right ventricle, which pumps it through the pulmonary artery to the lungs for oxygenation. Oxygenated blood returns to the left atrium via pulmonary veins, then moves to the left ventricle, which pumps it through the aorta to supply the entire body.

The heart wall consists of three layers: the epicardium (outer layer), myocardium (middle muscular layer), and endocardium (inner layer). The cardiac cycle includes systole (contraction) and diastole (relaxation). During systole, ventricles contract to pump blood out, while during diastole, they relax and fill with blood.

Blood Vessels and Circulation Arteries carry blood away from the heart and have thick, muscular walls to withstand high pressure. The largest artery is the aorta. Arteries branch into smaller arterioles, then into microscopic capillaries where gas and nutrient exchange occurs. Capillary walls are only one cell thick, facilitating diffusion. Venules collect blood from capillaries and merge into larger veins that return blood to the heart. Veins have thinner walls and contain valves to prevent backflow.

Blood Components Blood consists of plasma (55%) and formed elements (45%). Plasma is primarily water containing proteins, electrolytes, nutrients, and waste products. Red blood cells (erythrocytes) contain hemoglobin, which carries oxygen. White blood cells (leukocytes) fight infection and include neutrophils, lymphocytes, monocytes, eosinophils, and basophils. Platelets (thrombocytes) are essential for blood clotting.

Respiratory System

Respiratory Tract Structure The upper respiratory tract includes the nose, nasal cavity, pharynx, and larynx. The nose filters, warms, and humidifies incoming air. The pharynx serves as a common pathway for both respiratory and digestive systems. The larynx contains vocal cords and the epiglottis, which prevents food from entering the trachea during swallowing.

The lower respiratory tract consists of the trachea, bronchi, bronchioles, and alveoli. The trachea is supported by C-shaped cartilage rings and branches into two primary bronchi, one for each lung. Bronchi continue branching into smaller bronchioles, eventually terminating in tiny air sacs called alveoli.

Gas Exchange Process Alveoli are surrounded by dense capillary networks, creating an ideal environment for gas exchange. The respiratory membrane, consisting of the alveolar wall and capillary wall, is extremely thin (0.5 micrometers) to facilitate diffusion. Oxygen diffuses from alveoli into blood, while carbon dioxide diffuses from blood into alveoli for exhalation.

Breathing Mechanics Inspiration occurs when the diaphragm contracts and moves downward, while external intercostal muscles lift the ribs upward and outward. This increases thoracic cavity volume, decreasing pressure and drawing air into the lungs. Expiration is typically passive, resulting from elastic recoil of the lungs and relaxation of respiratory muscles.

Digestive System

Digestive Tract Anatomy The alimentary canal is a continuous tube extending from mouth to anus, including the oral cavity, esophagus, stomach, small intestine, and large intestine. Accessory organs include the teeth, tongue, salivary glands, liver, gallbladder, and pancreas.

Digestion Process Mechanical digestion begins in the mouth through chewing, while chemical digestion starts with salivary enzymes breaking down starches. The esophagus uses peristalsis (wave-like muscle contractions) to transport food to the stomach. In the stomach, gastric juice containing hydrochloric acid and pepsin begins protein digestion while mechanical churning creates chyme.

The small intestine, consisting of the duodenum, jejunum, and ileum, is the primary site of digestion and absorption. Pancreatic enzymes and bile from the liver complete the breakdown of nutrients. The intestinal wall contains millions of finger-like projections called villi, which increase surface area for absorption. Each villus contains a network of capillaries and a lymphatic vessel called a lacteal.

Absorption and Elimination Most nutrient absorption occurs in the small intestine. Carbohydrates and proteins enter the portal circulation to the liver, while fats enter the lymphatic system. The large intestine absorbs water and electrolytes, forming solid waste (feces) for elimination through the rectum and anus.

Nervous System

Central Nervous System The brain and spinal cord comprise the central nervous system (CNS). The brain consists of the cerebrum (conscious thought and voluntary movement), cerebellum (balance and coordination), and brainstem (vital functions like breathing and heart rate). The spinal cord transmits signals between the brain and peripheral nervous system.

Peripheral Nervous System All nervous tissue outside the CNS forms the peripheral nervous system (PNS). This includes cranial nerves, spinal nerves, and their branches. The PNS divides into somatic (voluntary skeletal muscle control) and autonomic (involuntary organ control) divisions.

Autonomic Nervous System The sympathetic division prepares the body for “fight or flight” responses, increasing heart rate, dilating pupils, and releasing stress hormones. The parasympathetic division promotes “rest and digest” activities, slowing heart rate, constricting pupils, and stimulating digestion.

Neuron Structure and Function Neurons consist of a cell body (soma), dendrites (receive signals), and an axon (transmits signals). Action potentials are electrical impulses that travel along axons. At synapses, chemical neurotransmitters cross the synaptic cleft to transmit signals between neurons or from neurons to muscles.

Musculoskeletal System

Skeletal System The adult skeleton contains 206 bones that provide structural support, protect organs, store minerals (calcium and phosphorus), and produce blood cells in bone marrow. Bones are classified by shape: long bones (femur), short bones (wrist bones), flat bones (skull), and irregular bones (vertebrae).

Bone Structure Compact bone forms the outer layer and provides strength, while spongy bone forms the inner layer and reduces weight. The periosteum is a membrane covering bones, containing blood vessels and cells for bone growth and repair. Bone matrix consists of collagen fibers and calcium phosphate crystals.

Muscle Types and Function Skeletal muscle attaches to bones via tendons and produces voluntary movement. These muscles are striated (striped appearance) due to organized protein filaments. Cardiac muscle, found only in the heart, is also striated but contracts involuntarily. Smooth muscle lacks striations and controls involuntary functions in organs like the digestive tract and blood vessels.

Muscle Contraction Skeletal muscle contraction occurs through the sliding filament mechanism. Actin and myosin filaments slide past each other when calcium ions are released, causing muscle shortening. ATP provides energy for this process.

Endocrine System

Hormone Classification and Function Hormones are chemical messengers that regulate body functions. Steroid hormones (like testosterone and estrogen) are lipid-soluble and can cross cell membranes directly. Protein hormones (like insulin and growth hormone) are water-soluble and bind to membrane receptors.

Major Endocrine Glands The pituitary gland, called the “master gland,” produces hormones that control other glands. The anterior pituitary releases growth hormone, thyroid-stimulating hormone, and reproductive hormones. The posterior pituitary releases antidiuretic hormone and oxytocin.

The thyroid gland produces thyroid hormones that regulate metabolism and calcitonin that lowers blood calcium. The parathyroid glands produce parathyroid hormone that raises blood calcium. The adrenal glands produce cortisol (stress response) and adrenaline (fight-or-flight response).

Urinary System

Kidney Structure and Function The kidneys filter blood to remove waste products and excess water, forming urine. Each kidney contains approximately one million nephrons, the functional units of filtration. Nephrons consist of a glomerulus (filtering cluster of capillaries) and a tubule system that processes the filtrate.

Urine Formation Filtration occurs in the glomerulus, where blood pressure forces water and small molecules into Bowman’s capsule. Reabsorption in the tubules returns essential substances like glucose and amino acids to the blood. Secretion adds additional wastes to the forming urine. The final urine travels through collecting ducts to the renal pelvis, then through ureters to the bladder for storage and eventual elimination.

System Interactions and Homeostasis

Cardiovascular-Respiratory Integration These systems work together for oxygen delivery and carbon dioxide removal. During exercise, increased oxygen demand triggers faster heart rate and breathing rate. Hemoglobin in red blood cells carries oxygen from lungs to tissues and returns carbon dioxide for elimination.

Nervous-Endocrine Coordination The hypothalamus links nervous and endocrine systems, controlling hormone release from the pituitary gland. Stress activates both sympathetic nervous responses and hormonal changes, demonstrating integrated system function.

Homeostatic Mechanisms Negative feedback loops maintain stable internal conditions. When blood glucose rises after eating, insulin is released to promote glucose uptake by cells. When blood pressure drops, sensors trigger heart rate increases and blood vessel constriction to restore normal pressure.

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Biology (9 Questions)

Cell Structure and Organization

Prokaryotic vs. Eukaryotic Cells Prokaryotic cells, found in bacteria and archaea, lack membrane-bound organelles and have genetic material freely floating in the cytoplasm. Their cell walls contain peptidoglycan (in bacteria), and they reproduce through binary fission. Some prokaryotes have flagella for movement and pili for attachment or genetic exchange.

Eukaryotic cells, found in plants, animals, fungi, and protists, contain membrane-bound organelles and a nucleus housing genetic material. This compartmentalization allows for specialized cellular functions and more complex organization.

Essential Organelles and Their Functions The nucleus serves as the cell’s control center, containing DNA organized into chromosomes. Nuclear pores regulate molecule transport between nucleus and cytoplasm. The nucleolus within the nucleus produces ribosomal RNA.

Mitochondria are the powerhouses of the cell, containing their own DNA and ribosomes. The inner mitochondrial membrane folds into cristae, increasing surface area for ATP production through cellular respiration. Muscle cells contain numerous mitochondria due to high energy demands.

The endoplasmic reticulum (ER) forms an extensive membrane network. Rough ER, studded with ribosomes, synthesizes proteins destined for secretion or membrane incorporation. Smooth ER lacks ribosomes and produces lipids, metabolizes carbohydrates, and detoxifies substances.

The Golgi apparatus modifies, packages, and ships proteins received from the ER. It consists of flattened membrane sacs called cisternae. Proteins move through the Golgi in vesicles, undergoing modifications like glycosylation.

Lysosomes contain digestive enzymes that break down cellular waste, worn-out organelles, and harmful substances. They maintain an acidic pH optimal for enzyme function. Lysosomes also participate in programmed cell death (apoptosis).

Plant Cell Specializations Chloroplasts conduct photosynthesis, containing chlorophyll and other pigments that capture light energy. The thylakoid membrane system within chloroplasts houses light-dependent reactions, while the stroma contains enzymes for light-independent reactions.

The cell wall provides structural support and protection, composed primarily of cellulose in plants. It’s more rigid than the flexible cell membrane and allows plants to maintain shape without skeletal systems.

The large central vacuole maintains turgor pressure, providing structural support and storing water, ions, and other substances. When water is abundant, the vacuole expands, keeping the plant rigid. Water loss causes wilting as turgor pressure decreases.

Cell Division and Reproduction

Mitosis: Somatic Cell Division Mitosis produces two genetically identical diploid daughter cells from one parent cell. The cell cycle includes interphase (G1, S, G2 phases) and M phase (mitosis and cytokinesis).

During prophase, chromatin condenses into visible chromosomes, each consisting of two sister chromatids joined at the centromere. The nuclear envelope dissolves, and centrioles move to opposite poles, forming the mitotic spindle.

In metaphase, chromosomes align at the cell’s equator (metaphase plate). Spindle fibers from opposite poles attach to kinetochores at each centromere, ensuring proper chromosome distribution.

Anaphase begins when sister chromatids separate and move to opposite cell poles. This ensures each daughter cell receives identical genetic information.

During telophase, nuclear envelopes reform around each set of chromosomes, which begin to decondense. Cytokinesis divides the cytoplasm, completing cell division.

Meiosis: Gamete Formation Meiosis reduces chromosome number by half, producing four genetically unique haploid gametes from one diploid parent cell. This process is essential for sexual reproduction and genetic diversity.

Meiosis I includes prophase I, where homologous chromosomes pair and exchange genetic material through crossing over. This recombination creates new gene combinations. Metaphase I aligns homologous pairs at the cell equator, followed by their separation in anaphase I.

Meiosis II resembles mitosis but starts with haploid cells. Sister chromatids separate, producing four haploid gametes with unique genetic combinations.

Genetics and Heredity

DNA Structure and Replication DNA consists of two complementary strands forming a double helix. Each strand contains nucleotides with four bases: adenine (A), thymine (T), guanine (G), and cytosine (C). Base pairing rules specify A pairs with T, and G pairs with C.

DNA replication is semi-conservative, meaning each new DNA molecule contains one original and one newly synthesized strand. The enzyme helicase unwinds the double helix, while DNA polymerase adds complementary nucleotides to each template strand.

RNA and Protein Synthesis RNA differs from DNA by containing ribose sugar, uracil instead of thymine, and being single-stranded. Three types of RNA participate in protein synthesis: messenger RNA (mRNA), transfer RNA (tRNA), and ribosomal RNA (rRNA).

Transcription occurs in the nucleus, where RNA polymerase uses DNA as a template to synthesize mRNA. The mRNA contains codons (three-base sequences) that specify amino acids.

Translation occurs at ribosomes in the cytoplasm. tRNA molecules carry specific amino acids and have anticodons complementary to mRNA codons. The ribosome facilitates peptide bond formation between amino acids, creating proteins.

Mendelian Genetics Genes exist in different versions called alleles. Dominant alleles mask the expression of recessive alleles in heterozygous individuals. An individual’s genotype refers to their genetic makeup, while phenotype refers to observable traits.

Punnett squares predict offspring ratios from parental crosses. A monohybrid cross between two heterozygotes (Aa × Aa) produces a 3:1 phenotypic ratio and a 1:2:1 genotypic ratio.

Sex-Linked Inheritance Sex-linked traits are carried on X or Y chromosomes. X-linked recessive traits appear more frequently in males because they have only one X chromosome. Color blindness and hemophilia are examples of X-linked recessive disorders.

Cellular Processes

Photosynthesis Photosynthesis converts light energy into chemical energy, producing glucose and oxygen from carbon dioxide and water. The overall equation is: 6CO₂ + 6H₂O + light energy → C₆H₁₂O₆ + 6O₂.

Light-dependent reactions occur in thylakoids, where chlorophyll absorbs light energy to split water molecules, releasing oxygen and energizing electrons. These reactions produce ATP and NADPH.

Light-independent reactions (Calvin cycle) occur in the stroma, using ATP and NADPH to convert carbon dioxide into glucose through carbon fixation, reduction, and regeneration phases.

Cellular Respiration Cellular respiration breaks down glucose to produce ATP, the cell’s energy currency. The complete equation is: C₆H₁₂O₆ + 6O₂ → 6CO₂ + 6H₂O + ATP.

Glycolysis occurs in the cytoplasm, partially breaking down glucose and producing pyruvate, ATP, and NADH. The Krebs cycle (citric acid cycle) in mitochondria completely oxidizes pyruvate, producing CO₂, ATP, NADH, and FADH₂.

The electron transport chain uses NADH and FADH₂ to generate most ATP through oxidative phosphorylation. Oxygen serves as the final electron acceptor, forming water.

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Chemistry (8 Questions)

Atomic Structure and Periodic Table

Atomic Components Atoms consist of protons (positive charge, mass ≈ 1 amu), neutrons (no charge, mass ≈ 1 amu), and electrons (negative charge, negligible mass). Protons and neutrons occupy the dense nucleus, while electrons orbit in energy levels or shells.

The atomic number equals the number of protons and defines the element. Mass number equals protons plus neutrons. Isotopes are atoms of the same element with different numbers of neutrons.

Electron Configuration Electrons occupy specific energy levels around the nucleus. The first shell holds a maximum of 2 electrons, the second holds 8, the third holds 18, and the fourth holds 32. Valence electrons in the outermost shell determine chemical reactivity and bonding behavior.

Periodic Table Organization Elements are arranged by increasing atomic number. Periods (horizontal rows) contain elements with the same number of electron shells. Groups or families (vertical columns) contain elements with similar chemical properties due to identical numbers of valence electrons.

Periodic Trends Atomic radius decreases across periods as nuclear charge increases, pulling electrons closer. Atomic radius increases down groups as additional electron shells are added. Ionization energy (energy to remove an electron) increases across periods and decreases down groups. Electronegativity (attraction for electrons in bonds) follows similar patterns to ionization energy.

Chemical Bonding

Ionic Bonding Ionic bonds form when electrons transfer from metals to nonmetals, creating charged ions. Metals lose electrons to form positive cations, while nonmetals gain electrons to form negative anions. Electrostatic attraction between oppositely charged ions creates the ionic bond.

Sodium chloride (NaCl) exemplifies ionic bonding. Sodium (Na) loses its single valence electron to chlorine (Cl), which has seven valence electrons. This transfer gives both atoms stable electron configurations, with Na⁺ and Cl⁻ ions held together by electrostatic forces.

Ionic compounds typically have high melting and boiling points, conduct electricity when dissolved or molten, and form crystalline structures. They’re generally soluble in polar solvents like water.

Covalent Bonding Covalent bonds form when atoms share electron pairs. This typically occurs between nonmetals with similar electronegativity values. Single bonds share one electron pair, double bonds share two pairs, and triple bonds share three pairs.

Water (H₂O) demonstrates covalent bonding, with oxygen sharing electrons with two hydrogen atoms. The shared electrons create a stable electron configuration for all atoms involved.

Covalent compounds often have lower melting and boiling points than ionic compounds, don’t conduct electricity, and may be gases, liquids, or soft solids at room temperature.

Molecular Polarity Polar molecules have uneven electron distribution due to differences in electronegativity between bonded atoms. Water is polar because oxygen is more electronegative than hydrogen, creating partial negative and positive charges.

Nonpolar molecules have even electron distribution, either because atoms have identical electronegativity or because molecular geometry cancels out polar bonds.

States of Matter and Phase Changes

Kinetic Molecular Theory All matter consists of particles in constant motion. Temperature reflects average kinetic energy of particles. In solids, particles vibrate around fixed positions in organized arrangements. In liquids, particles move more freely but remain close together. In gases, particles move rapidly and independently with minimal intermolecular forces.

Phase Transitions Phase changes involve energy transfer without temperature change. Melting (solid to liquid) and vaporization (liquid to gas) require energy input to overcome intermolecular forces. Freezing (liquid to solid) and condensation (gas to liquid) release energy as intermolecular forces form.

Sublimation occurs when solids transition directly to gases, while deposition is the reverse process. Dry ice (solid CO₂) sublimates at room temperature and pressure.

Chemical Reactions and Equations

Types of Chemical Reactions Synthesis reactions combine reactants to form products (A + B → AB). Decomposition reactions break compounds into simpler substances (AB → A + B). Single replacement reactions involve one element replacing another in a compound (A + BC → AC + B). Double replacement reactions exchange ions between compounds (AB + CD → AD + CB).

Combustion reactions involve rapid oxidation, typically with oxygen, producing heat and light. Hydrocarbon combustion produces carbon dioxide and water.

Balancing Chemical Equations Chemical equations must have equal numbers of each type of atom on both sides, following the law of conservation of mass. Use coefficients (whole numbers) to balance equations without changing chemical formulas.

For example, balancing the combustion of methane: CH₄ + 2O₂ → CO₂ + 2H₂O. This shows one methane molecule reacting with two oxygen molecules to produce one carbon dioxide molecule and two water molecules.

Solutions and pH

Solution Terminology Solutions are homogeneous mixtures where solute dissolves in solvent. Concentration describes the amount of solute per unit of solution. Molarity (M) expresses moles of solute per liter of solution.

Solubility depends on intermolecular forces between solute and solvent. “Like dissolves like” means polar substances dissolve in polar solvents, while nonpolar substances dissolve in nonpolar solvents.

Acids, Bases, and pH Acids release hydrogen ions (H⁺) in solution, while bases release hydroxide ions (OH⁻) or accept hydrogen ions. The pH scale measures acidity from 0-14, with 7 being neutral. Values below 7 are acidic, above 7 are basic (alkaline).

Each pH unit represents a 10-fold change in hydrogen ion concentration. Stomach acid has pH ≈ 1-2, while household ammonia has pH ≈ 11-12. Buffer systems maintain stable pH by neutralizing added acids or bases.

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Scientific Reasoning (9 Questions)

Experimental Design Principles

Hypothesis Formation Scientific hypotheses must be testable and falsifiable, meaning they can be proven wrong through experimentation. A good hypothesis predicts specific outcomes based on current understanding and can be tested using available methods.

Hypotheses should be written as “if-then” statements that clearly identify the independent variable (cause) and dependent variable (effect). For example: “If plant fertilizer increases soil nitrogen content, then plants will grow taller.”

Variables in Experiments Independent variables are deliberately manipulated by the researcher to test their effects. Dependent variables are measured responses that may change due to independent variable manipulation. Controlled variables remain constant throughout the experiment to ensure only the independent variable affects results.

Control Groups Control groups provide baseline comparisons for experimental groups. Negative controls demonstrate no expected effect, while positive controls show expected results. Without proper controls, it’s impossible to determine whether observed changes result from experimental treatments or other factors.

Experimental Controls Controlling variables eliminates confounding factors that might influence results. Randomization reduces bias by randomly assigning subjects to experimental and control groups. Blinding prevents researcher or subject expectations from influencing results.

Sample size affects result reliability and statistical significance. Larger samples reduce random variation effects and increase confidence in conclusions. Replication by independent researchers validates findings and builds scientific consensus.

Data Analysis and Interpretation

Types of Data Quantitative data consists of numerical measurements that can be analyzed statistically. Qualitative data describes characteristics or qualities that can’t be easily quantified. Both types provide valuable information but require different analysis approaches.

Graphical Data Presentation Line graphs effectively show changes over time or continuous relationships between variables. Bar graphs compare discrete categories or groups. Scatter plots reveal correlations between two continuous variables. Pie charts display parts of a whole as percentages.

When interpreting graphs, examine axis labels, scales, and units carefully. Look for trends, patterns, and outliers. Consider whether relationships are linear or nonlinear, positive or negative.

Statistical Measures The mean (average) provides a central tendency measure but can be affected by extreme values. The median (middle value) is less affected by outliers and better represents typical values in skewed distributions. The mode identifies the most frequently occurring value.

Range describes data spread from minimum to maximum values. Standard deviation measures how much individual values vary from the mean. Smaller standard deviations indicate more consistent data.

Correlation vs. Causation Correlation describes relationships between variables but doesn’t prove causation. Strong correlations may result from coincidence, common underlying causes, or genuine causal relationships. Establishing causation requires controlled experiments that manipulate independent variables while controlling other factors.

Scientific Method Application

Observation and Question Formation Scientific inquiry begins with careful observations that lead to testable questions. Good scientific questions are specific, measurable, and answerable through experimentation or systematic observation.

Literature Review Before designing experiments, scientists review existing research to understand current knowledge, identify gaps, and avoid duplicating previous work. Literature reviews help form hypotheses based on established scientific principles.

Methodology Selection Different research questions require different methodological approaches. Laboratory experiments provide controlled conditions but may lack real-world applicability. Field studies offer realistic conditions but less control over variables. Surveys and observational studies can identify patterns but can’t establish causation.

Data Collection and Analysis Systematic data collection follows predetermined protocols to ensure consistency and reduce bias. Statistical analysis determines whether observed differences are significant or likely due to chance variation.

Drawing Conclusions Valid conclusions directly relate to collected data and avoid overgeneralization beyond the experimental scope. Scientists must consider alternative explanations for their results and identify limitations that might affect interpretation.

Critical Thinking in Science

Evaluating Scientific Evidence Source credibility affects evidence reliability. Peer-reviewed publications in established journals provide more credible evidence than unverified claims or biased sources. Consider author qualifications, funding sources, and potential conflicts of interest.

Sample size and methodology quality affect conclusion validity. Small samples may not represent larger populations, while flawed methodology can produce misleading results.

Identifying Bias Selection bias occurs when samples don’t represent target populations. Confirmation bias leads researchers to favor evidence supporting their preconceptions while ignoring contradictory evidence. Publication bias results from preferential publication of positive results while negative results remain unpublished.

Logical Reasoning Deductive reasoning starts with general principles and applies them to specific situations. Inductive reasoning draws general conclusions from specific observations. Both approaches are valuable but have limitations and potential sources of error.

Scientific Consensus Scientific consensus develops through repeated testing, peer review, and independent verification. Consensus doesn’t mean unanimous agreement but reflects the weight of evidence and expert opinion. Scientific understanding evolves as new evidence emerges.

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Test-Taking Strategies for Success

Time Management

With 60 minutes for 50 questions, you have approximately 1.2 minutes per question. Don’t spend too much time on difficult questions initially. Mark challenging questions and return to them if time permits.

Question Analysis

Read questions carefully, identifying key terms that indicate specific concepts or processes. Look for qualifiers like “most likely,” “primarily,” or “directly” that narrow answer choices.

Process of Elimination

Eliminate obviously incorrect answers first, then choose from remaining options. Look for absolute terms like “always,” “never,” or “all” which are often incorrect in scientific contexts where exceptions exist.

Applied Knowledge

Many questions test your ability to apply knowledge to new situations rather than simply recall facts. Focus on understanding underlying principles and relationships between concepts.

Answer Selection

When unsure between two answers, consider which is more specific and directly addresses the question. Avoid overthinking simple questions, but be cautious of answers that seem too obvious for complex topics.

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Final Preparation Checklist

Before your TEAS Science exam, ensure you can:

Human Anatomy & Physiology:

• ✓ Identify all major body systems and their primary functions
• ✓ Explain interactions between cardiovascular and respiratory systems
• ✓ Describe nervous system divisions and their roles
• ✓ Understand hormone functions and feedback mechanisms
• ✓ Explain digestion, absorption, and elimination processes

Biology:

• ✓ Distinguish between prokaryotic and eukaryotic cell structures
• ✓ Compare mitosis and meiosis processes and outcomes
• ✓ Understand DNA structure, replication, and protein synthesis
• ✓ Apply Mendelian genetics principles to inheritance problems
• ✓ Explain photosynthesis and cellular respiration processes

Chemistry:

• ✓ Identify atomic structure components and electron configurations
• ✓ Understand periodic table organization and trends
• ✓ Distinguish between ionic and covalent bonding mechanisms
• ✓ Balance chemical equations and identify reaction types
• ✓ Interpret pH scale and solution concepts

Scientific Reasoning:

• ✓ Design controlled experiments with appropriate variables
• ✓ Analyze data presentations and identify trends
• ✓ Distinguish between correlation and causation
• ✓ Evaluate experimental design quality and potential limitations
• ✓ Apply critical thinking to scientific claims and evidence

Success on the TEAS Science section requires both knowledge of core concepts and ability to apply scientific reasoning. Focus on understanding connections between topics rather than memorizing isolated facts. Practice applying your knowledge to unfamiliar scenarios, as this mirrors the exam’s emphasis on critical thinking and application.

Remember that science is interconnected—concepts from one area often relate to others. Understanding these relationships will help you answer questions even when you’re unsure of specific details.

Good luck with your TEAS exam!