ATI TEAS SCIENCE QUESTIONS AND CORRECT ANSWERS (VERIFIED ANSWERS) PLUS RATIONALES 2026 Q&A
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Core Domains
Human Anatomy and Physiology
Biology (Microbiology, Cellular, and Molecular)
Chemistry (General and Organic)
Scientific Reasoning and Measurement
Genetics and Heredity
Immune System and Pathophysiology
Homeostasis and Organ System Interactions
Research Methods and Data Interpretation
Introduction
This assessment is designed to evaluate foundational knowledge in scientific concepts essential for success in
health science programs. It measures understanding of human body systems, biological principles, chemical
processes, and scientific inquiry. Each multiple-choice question targets recall, application, and critical thinking.
Scenario-based items simulate real-world clinical and laboratory decisions. The format reflects the rigor and
structure of standardized entrance examinations. Mastery requires integration of theory with practical reasoning.
Prepare to analyze, differentiate, and apply science to patient care and diagnostic contexts. Accuracy and rationale
comprehension are paramount.
,SECTION ONE: QUESTIONS 1–100
Question 1
Which of the following describes the primary function of the ribosomes within a eukaryotic cell?
A. Lipid synthesis and detoxification
B. ATP production via oxidative phosphorylation
C. Protein synthesis through translation of mRNA
D. Modification and packaging of secretory proteins
🟢C
🔴 RATIONALE: Ribosomes are the site of protein synthesis, where mRNA is translated into polypeptide chains.
Option A describes smooth ER functions; option B describes mitochondria; option D describes Golgi apparatus.
Question 2
A patient has a blood pH of 7.25. Which condition is most consistent with this value?
A. Respiratory alkalosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Normal pH
🟢C
🔴 RATIONALE: Normal arterial pH is 7.35–7.45. A pH of 7.25 indicates acidosis. Respiratory acidosis results
from hypoventilation and CO2 retention. Alkalosis options are incorrect; normal is false.
,Question 3
Which of the following enzymes is responsible for breaking down starches into disaccharides in the mouth?
A. Pepsin
B. Lipase
C. Amylase
D. Trypsin
🟢C
🔴 RATIONALE: Salivary amylase (ptyalin) initiates starch digestion in the oral cavity. Pepsin digests proteins in
the stomach; lipase digests fats; trypsin digests proteins in the small intestine.
Question 4
In a scientific experiment, the group that does not receive the treatment is called the:
A. Control group
B. Experimental group
C. Placebo group
D. Dependent variable group
🟢A
🔴 RATIONALE: The control group is untreated to provide a baseline for comparison. Experimental group
receives treatment; placebo is a specific type of control; dependent variable is measured outcome.
Question 5
Which of the following structures is part of the central nervous system (CNS)?
, A. Spinal nerves
B. Ganglia
C. Spinal cord
D. Sensory receptors
🟢C
🔴 RATIONALE: CNS consists of brain and spinal cord. Spinal nerves and ganglia are part of peripheral nervous
system; sensory receptors are afferent endings.
Question 6
A genetic mutation results in a single amino acid change in hemoglobin. This is an example of:
A. Frameshift mutation
B. Silent mutation
C. Missense mutation
D. Nonsense mutation
🟢C
🔴 RATIONALE: Missense mutation changes one amino acid to another. Frameshift alters reading frame; silent
does not change amino acid; nonsense creates premature stop codon.
Question 7
Which of the following is the primary role of the lymphatic system?
A. Transport of oxygen to tissues
B. Return of interstitial fluid to the bloodstream
| INSTANT DOWNLOAD PDF
Core Domains
Human Anatomy and Physiology
Biology (Microbiology, Cellular, and Molecular)
Chemistry (General and Organic)
Scientific Reasoning and Measurement
Genetics and Heredity
Immune System and Pathophysiology
Homeostasis and Organ System Interactions
Research Methods and Data Interpretation
Introduction
This assessment is designed to evaluate foundational knowledge in scientific concepts essential for success in
health science programs. It measures understanding of human body systems, biological principles, chemical
processes, and scientific inquiry. Each multiple-choice question targets recall, application, and critical thinking.
Scenario-based items simulate real-world clinical and laboratory decisions. The format reflects the rigor and
structure of standardized entrance examinations. Mastery requires integration of theory with practical reasoning.
Prepare to analyze, differentiate, and apply science to patient care and diagnostic contexts. Accuracy and rationale
comprehension are paramount.
,SECTION ONE: QUESTIONS 1–100
Question 1
Which of the following describes the primary function of the ribosomes within a eukaryotic cell?
A. Lipid synthesis and detoxification
B. ATP production via oxidative phosphorylation
C. Protein synthesis through translation of mRNA
D. Modification and packaging of secretory proteins
🟢C
🔴 RATIONALE: Ribosomes are the site of protein synthesis, where mRNA is translated into polypeptide chains.
Option A describes smooth ER functions; option B describes mitochondria; option D describes Golgi apparatus.
Question 2
A patient has a blood pH of 7.25. Which condition is most consistent with this value?
A. Respiratory alkalosis
B. Metabolic alkalosis
C. Respiratory acidosis
D. Normal pH
🟢C
🔴 RATIONALE: Normal arterial pH is 7.35–7.45. A pH of 7.25 indicates acidosis. Respiratory acidosis results
from hypoventilation and CO2 retention. Alkalosis options are incorrect; normal is false.
,Question 3
Which of the following enzymes is responsible for breaking down starches into disaccharides in the mouth?
A. Pepsin
B. Lipase
C. Amylase
D. Trypsin
🟢C
🔴 RATIONALE: Salivary amylase (ptyalin) initiates starch digestion in the oral cavity. Pepsin digests proteins in
the stomach; lipase digests fats; trypsin digests proteins in the small intestine.
Question 4
In a scientific experiment, the group that does not receive the treatment is called the:
A. Control group
B. Experimental group
C. Placebo group
D. Dependent variable group
🟢A
🔴 RATIONALE: The control group is untreated to provide a baseline for comparison. Experimental group
receives treatment; placebo is a specific type of control; dependent variable is measured outcome.
Question 5
Which of the following structures is part of the central nervous system (CNS)?
, A. Spinal nerves
B. Ganglia
C. Spinal cord
D. Sensory receptors
🟢C
🔴 RATIONALE: CNS consists of brain and spinal cord. Spinal nerves and ganglia are part of peripheral nervous
system; sensory receptors are afferent endings.
Question 6
A genetic mutation results in a single amino acid change in hemoglobin. This is an example of:
A. Frameshift mutation
B. Silent mutation
C. Missense mutation
D. Nonsense mutation
🟢C
🔴 RATIONALE: Missense mutation changes one amino acid to another. Frameshift alters reading frame; silent
does not change amino acid; nonsense creates premature stop codon.
Question 7
Which of the following is the primary role of the lymphatic system?
A. Transport of oxygen to tissues
B. Return of interstitial fluid to the bloodstream
