ATI TEAS 7 SCIENCE ACTUAL TEST 2026 –QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS)
PLUS RATIONALES 2026 Q&A | INSTANT DOWNLOAD PDF.
CORE DOMAINS
Human Anatomy and Physiology
Biology and Cellular Processes
Chemistry and Atomic Structure
Scientific Reasoning and Methodology
Genetics and Heredity
Physical Sciences and Earth Science
Pathophysiology and Disease Prevention
Biological Systems Integration
INTRODUCTION
The ATI TEAS 7 Science Assessment is designed to evaluate the foundational knowledge and critical thinking
skills required for entry-level health science programs. This comprehensive exam covers essential scientific
principles across multiple disciplines, ensuring candidates possess the academic readiness necessary for clinical
success. The assessment utilizes a blend of multiple-choice and complex scenario-based questions to measure a
candidate's ability to apply theoretical concepts to real-world medical and laboratory environments. By
emphasizing decision-making and the integration of biological systems, this exam serves as a rigorous
benchmark for identifying individuals capable of navigating the scientific complexities of the modern healthcare
landscape.
SECTION ONE: QUESTIONS 1–100
, 1. Which of the following organelles is responsible for the synthesis of lipids and the detoxification of harmful
substances within the cell?
A. Rough endoplasmic reticulum
B. Golgi apparatus
🟢 C. Smooth endoplasmic reticulum
D. Mitochondria
🔴 RATIONALE: The smooth endoplasmic reticulum lacks ribosomes and is the primary site for lipid synthesis
and metabolic detoxification. The rough ER is primarily involved in protein synthesis.
2. In the human respiratory system, which structure is the primary site for gas exchange between the air and
the blood?
A. Bronchioles
🟢 B. Alveoli
C. Trachea
D. Pharynx
🔴 RATIONALE: Alveoli are tiny air sacs with thin walls that allow for the diffusion of oxygen into the blood and
carbon dioxide out of the blood.
3. Which of the following valves prevents the backflow of blood from the right ventricle into the right atrium?
🟢 A. Tricuspid valve
B. Mitral valve
C. Pulmonary valve
D. Aortic valve
,🔴 RATIONALE: The tricuspid valve is the atrioventricular valve located between the right atrium and right
ventricle. The mitral valve is on the left side of the heart.
4. A researcher is studying the effect of temperature on the rate of a chemical reaction. In this experiment, the
independent variable is:
A. The reaction rate
B. The volume of the reactants
🟢 C. The temperature
D. The concentration of the catalyst
🔴 RATIONALE: The independent variable is the factor that is intentionally changed or manipulated by the
researcher to observe its effects.
5. Which layer of the skin contains the melanocytes responsible for skin pigmentation?
A. Dermis
B. Hypodermis
🟢 C. Epidermis
D. Stratum corneum
🔴 RATIONALE: Melanocytes are found in the basal layer of the epidermis (stratum basale) and produce
melanin, which protects the skin from UV radiation.
6. Which of the following describes a physical change rather than a chemical change?
A. Iron rusting in the presence of oxygen
🟢 B. Water evaporating into steam
, C. Wood burning in a fireplace
D. An acid neutralizing a base
🔴 RATIONALE: Evaporation is a change in the state of matter (liquid to gas) without altering the chemical
composition of the substance.
7. What is the functional unit of the kidney responsible for filtering blood and forming urine?
A. Ureter
B. Glomerulus
🟢 C. Nephron
D. Renal pelvis
🔴 RATIONALE: The nephron is the structural and functional unit of the kidney where filtration, reabsorption, and
secretion occur.
8. Which of the following best describes the process of osmosis?
A. Movement of solutes from high concentration to low concentration
🟢 B. Movement of water across a semipermeable membrane from low solute to high solute concentration
C. Active transport of ions across a cell membrane using ATP
D. The engulfing of large particles by a cell membrane
🔴 RATIONALE: Osmosis specifically refers to the passive movement of water molecules to balance solute
concentrations across a membrane.
9. In a Mendelian cross, if a homozygous dominant (YY) plant is crossed with a homozygous recessive (yy)
plant, what is the probability that the offspring will express the recessive phenotype?
PLUS RATIONALES 2026 Q&A | INSTANT DOWNLOAD PDF.
CORE DOMAINS
Human Anatomy and Physiology
Biology and Cellular Processes
Chemistry and Atomic Structure
Scientific Reasoning and Methodology
Genetics and Heredity
Physical Sciences and Earth Science
Pathophysiology and Disease Prevention
Biological Systems Integration
INTRODUCTION
The ATI TEAS 7 Science Assessment is designed to evaluate the foundational knowledge and critical thinking
skills required for entry-level health science programs. This comprehensive exam covers essential scientific
principles across multiple disciplines, ensuring candidates possess the academic readiness necessary for clinical
success. The assessment utilizes a blend of multiple-choice and complex scenario-based questions to measure a
candidate's ability to apply theoretical concepts to real-world medical and laboratory environments. By
emphasizing decision-making and the integration of biological systems, this exam serves as a rigorous
benchmark for identifying individuals capable of navigating the scientific complexities of the modern healthcare
landscape.
SECTION ONE: QUESTIONS 1–100
, 1. Which of the following organelles is responsible for the synthesis of lipids and the detoxification of harmful
substances within the cell?
A. Rough endoplasmic reticulum
B. Golgi apparatus
🟢 C. Smooth endoplasmic reticulum
D. Mitochondria
🔴 RATIONALE: The smooth endoplasmic reticulum lacks ribosomes and is the primary site for lipid synthesis
and metabolic detoxification. The rough ER is primarily involved in protein synthesis.
2. In the human respiratory system, which structure is the primary site for gas exchange between the air and
the blood?
A. Bronchioles
🟢 B. Alveoli
C. Trachea
D. Pharynx
🔴 RATIONALE: Alveoli are tiny air sacs with thin walls that allow for the diffusion of oxygen into the blood and
carbon dioxide out of the blood.
3. Which of the following valves prevents the backflow of blood from the right ventricle into the right atrium?
🟢 A. Tricuspid valve
B. Mitral valve
C. Pulmonary valve
D. Aortic valve
,🔴 RATIONALE: The tricuspid valve is the atrioventricular valve located between the right atrium and right
ventricle. The mitral valve is on the left side of the heart.
4. A researcher is studying the effect of temperature on the rate of a chemical reaction. In this experiment, the
independent variable is:
A. The reaction rate
B. The volume of the reactants
🟢 C. The temperature
D. The concentration of the catalyst
🔴 RATIONALE: The independent variable is the factor that is intentionally changed or manipulated by the
researcher to observe its effects.
5. Which layer of the skin contains the melanocytes responsible for skin pigmentation?
A. Dermis
B. Hypodermis
🟢 C. Epidermis
D. Stratum corneum
🔴 RATIONALE: Melanocytes are found in the basal layer of the epidermis (stratum basale) and produce
melanin, which protects the skin from UV radiation.
6. Which of the following describes a physical change rather than a chemical change?
A. Iron rusting in the presence of oxygen
🟢 B. Water evaporating into steam
, C. Wood burning in a fireplace
D. An acid neutralizing a base
🔴 RATIONALE: Evaporation is a change in the state of matter (liquid to gas) without altering the chemical
composition of the substance.
7. What is the functional unit of the kidney responsible for filtering blood and forming urine?
A. Ureter
B. Glomerulus
🟢 C. Nephron
D. Renal pelvis
🔴 RATIONALE: The nephron is the structural and functional unit of the kidney where filtration, reabsorption, and
secretion occur.
8. Which of the following best describes the process of osmosis?
A. Movement of solutes from high concentration to low concentration
🟢 B. Movement of water across a semipermeable membrane from low solute to high solute concentration
C. Active transport of ions across a cell membrane using ATP
D. The engulfing of large particles by a cell membrane
🔴 RATIONALE: Osmosis specifically refers to the passive movement of water molecules to balance solute
concentrations across a membrane.
9. In a Mendelian cross, if a homozygous dominant (YY) plant is crossed with a homozygous recessive (yy)
plant, what is the probability that the offspring will express the recessive phenotype?
