ATI TEAS 2026 Complete Exam Page 1
ATI TEAS 2026 Complete Exam
Test of Essential Academic Skills
Total Questions 200 Time Limit 209 Minutes
Science 50 Questions Mathematics 50 Questions
Reading 50 Questions English & Language 50 Questions
Usage
Instructions: Read each question carefully. Select the best answer from the choices
provided. Each question is followed by the correct answer and a detailed rationale.
Section 1 Science
1. Which of the following organelles is responsible for producing ATP through cellular
respiration?
A. Golgiapparatus
B. Mitochondria
C. Smooth endoplasmic reticulum
D. Lysosomes
Answer: B
Rationale:: Mitochondria are the primary sites of ATP production through aerobic
cellular respiration, including the Krebs cycle and electron transport chain. The Golgi
apparatus processes and packages proteins, the smooth ER synthesizes lipids, and
lysosomes contain digestive enzymes.
2. What is the primary function of the stratified squamous epithelium in the human
body?
A. Absorption of nutrients
B. Secretion of hormones
C. Protection against mechanical stress
D. Filtration of blood
Answer: C
Rationale:: Stratified squamous epithelium consists of multiple layers of flat cells
designed to protect underlying tissues from abrasion, friction, and mechanical stress. It
is found in the skin, oral cavity, esophagus, and vagina. Simple columnar epithelium is
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
,ATI TEAS 2026 Complete Exam Page 2
better suited for absorption, while endocrine glands secrete hormones.
3. Which chamber of the heart pumps oxygenated blood to the systemic circulation?
A. Right atrium
B. Right ventricle
C. Left atrium
D. Left ventricle
Answer: D
Rationale:: The left ventricle receives oxygenated blood from the left atrium and
pumps it through the aorta to the systemic circulation. It has the thickest muscular
wall of all four chambers because it must generate sufficient pressure to push blood
throughout the entire body. The right ventricle pumps deoxygenated blood to the
lungs.
4. The enzyme pepsin functions optimally in which of the following environments?
A. Neutral pH (7.0)
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
,ATI TEAS 2026 Complete Exam Page 3
B. Alkaline pH (8.5)
C. Acidic pH (1.5-2.0)
D. Slightly acidic pH (5.5-6.0)
Answer: C
Rationale:: Pepsin is a proteolytic enzyme secreted by chief cells in the stomach as the
inactive zymogen pepsinogen. It is activated by hydrochloric acid (HCl) and functions
optimally at a highly acidic pH of 1.5 to 2.0. This acidic environment denatures dietary
proteins, making them more accessible to enzymatic cleavage.
5. Which of the following structures is part of the central nervous system?
A. Spinal nerves
B. Cranial nerves
C. Spinal cord
D. Ganglia
Answer: C
Rationale:: The central nervous system (CNS) consists of the brain and spinal cord.
Spinal nerves, cranial nerves, and ganglia are all components of the peripheral
nervous system (PNS). The CNS processes information and coordinates responses,
while the PNS transmits signals between the CNS and the rest of the body.
6. During which phase of the cell cycle does DNA replication occur?
A. G1 phase
B. S phase
C. G2 phase
D. M phase
Answer: B
Rationale:: DNA replication occurs during the S (synthesis) phase of interphase.
During this phase, each chromosome is duplicated to produce two sister chromatids.
G1 is a growth phase before replication, G2 is a preparation phase before mitosis, and
M phase is when mitosis and cytokinesis occur.
7. Which type of cell division produces gametes with half the chromosome number?
A. Mitosis
B. Meiosis
C. Binary fission
D. Budding
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
, ATI TEAS 2026 Complete Exam Page 4
Answer: B
Rationale:: Meiosis is a specialized form of cell division that reduces the
chromosome number by half, producing four haploid gametes from one diploid cell.
This process includes two rounds of division (Meiosis I and II) and introduces
genetic variation through crossing over and independent assortment. Mitosis
produces genetically identical diploid cells.
8. What is the role of ribosomes in protein synthesis?
A. Transcribing DNA into mRNA
B. Translating mRNA into polypeptide chains
C. Splicing introns from pre-mRNA
D. Degrading misfolded proteins
Answer: B
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
ATI TEAS 2026 Complete Exam
Test of Essential Academic Skills
Total Questions 200 Time Limit 209 Minutes
Science 50 Questions Mathematics 50 Questions
Reading 50 Questions English & Language 50 Questions
Usage
Instructions: Read each question carefully. Select the best answer from the choices
provided. Each question is followed by the correct answer and a detailed rationale.
Section 1 Science
1. Which of the following organelles is responsible for producing ATP through cellular
respiration?
A. Golgiapparatus
B. Mitochondria
C. Smooth endoplasmic reticulum
D. Lysosomes
Answer: B
Rationale:: Mitochondria are the primary sites of ATP production through aerobic
cellular respiration, including the Krebs cycle and electron transport chain. The Golgi
apparatus processes and packages proteins, the smooth ER synthesizes lipids, and
lysosomes contain digestive enzymes.
2. What is the primary function of the stratified squamous epithelium in the human
body?
A. Absorption of nutrients
B. Secretion of hormones
C. Protection against mechanical stress
D. Filtration of blood
Answer: C
Rationale:: Stratified squamous epithelium consists of multiple layers of flat cells
designed to protect underlying tissues from abrasion, friction, and mechanical stress. It
is found in the skin, oral cavity, esophagus, and vagina. Simple columnar epithelium is
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
,ATI TEAS 2026 Complete Exam Page 2
better suited for absorption, while endocrine glands secrete hormones.
3. Which chamber of the heart pumps oxygenated blood to the systemic circulation?
A. Right atrium
B. Right ventricle
C. Left atrium
D. Left ventricle
Answer: D
Rationale:: The left ventricle receives oxygenated blood from the left atrium and
pumps it through the aorta to the systemic circulation. It has the thickest muscular
wall of all four chambers because it must generate sufficient pressure to push blood
throughout the entire body. The right ventricle pumps deoxygenated blood to the
lungs.
4. The enzyme pepsin functions optimally in which of the following environments?
A. Neutral pH (7.0)
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
,ATI TEAS 2026 Complete Exam Page 3
B. Alkaline pH (8.5)
C. Acidic pH (1.5-2.0)
D. Slightly acidic pH (5.5-6.0)
Answer: C
Rationale:: Pepsin is a proteolytic enzyme secreted by chief cells in the stomach as the
inactive zymogen pepsinogen. It is activated by hydrochloric acid (HCl) and functions
optimally at a highly acidic pH of 1.5 to 2.0. This acidic environment denatures dietary
proteins, making them more accessible to enzymatic cleavage.
5. Which of the following structures is part of the central nervous system?
A. Spinal nerves
B. Cranial nerves
C. Spinal cord
D. Ganglia
Answer: C
Rationale:: The central nervous system (CNS) consists of the brain and spinal cord.
Spinal nerves, cranial nerves, and ganglia are all components of the peripheral
nervous system (PNS). The CNS processes information and coordinates responses,
while the PNS transmits signals between the CNS and the rest of the body.
6. During which phase of the cell cycle does DNA replication occur?
A. G1 phase
B. S phase
C. G2 phase
D. M phase
Answer: B
Rationale:: DNA replication occurs during the S (synthesis) phase of interphase.
During this phase, each chromosome is duplicated to produce two sister chromatids.
G1 is a growth phase before replication, G2 is a preparation phase before mitosis, and
M phase is when mitosis and cytokinesis occur.
7. Which type of cell division produces gametes with half the chromosome number?
A. Mitosis
B. Meiosis
C. Binary fission
D. Budding
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
, ATI TEAS 2026 Complete Exam Page 4
Answer: B
Rationale:: Meiosis is a specialized form of cell division that reduces the
chromosome number by half, producing four haploid gametes from one diploid cell.
This process includes two rounds of division (Meiosis I and II) and introduces
genetic variation through crossing over and independent assortment. Mitosis
produces genetically identical diploid cells.
8. What is the role of ribosomes in protein synthesis?
A. Transcribing DNA into mRNA
B. Translating mRNA into polypeptide chains
C. Splicing introns from pre-mRNA
D. Degrading misfolded proteins
Answer: B
200 Questions with Answers and Rationales | Science | Mathematics | Reading | English & Language Usage
