ATI TEAS VI 6 Science Official Exam 2026/2027
Actual Exam Complete Questions and Answers
Detailed Rationales Pass Guaranteed - A+ Graded
TABLE OF CONTENTS
Section 1 | Human Anatomy and Physiology | Q1 – Q10
Section 2 | Biology and Life Sciences | Q11 – Q20
Section 3 | Chemistry and Chemical Reactions | Q21 – Q30
Section 4 | Scientific Measurement and Data Interpretation | Q31 – Q40
Section 5 | Scientific Reasoning and Problem Solving | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
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SECTION 1: HUMAN ANATOMY AND PHYSIOLOGY Q1 – Q10
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Question 1 of 50
A 68-year-old male patient arrives at the emergency department complaining of
crushing chest pain radiating to his left arm. His blood pressure is 180/110 mmHg and
an ECG shows ST-segment elevation.
A. Increased cardiac output and peripheral vascular resistance
B. Decreased venous return to the right atrium
C. Reduced sensitivity of baroreceptor reflexes
D. Excessive parasympathetic stimulation of the sinoatrial node
Correct Answer: A
Rationale: Systemic blood pressure is determined primarily by cardiac output and total
peripheral resistance, so an acute hypertensive episode in a cardiac event reflects
increased cardiac workload and vasoconstriction. Decreased venous return would
typically lower preload and reduce cardiac output rather than raise blood pressure. In
,clinical practice, managing both cardiac output and vascular resistance is essential
when treating hypertensive emergencies.
Question 2 of 50
A 7-year-old child with asthma is brought to the clinic during a mild exacerbation. The
provider notes bilateral wheezing and a prolonged expiratory phase on auscultation.
A. Passive recoil of the chest wall during inspiration
B. Expiration driven by elastic recoil of the alveoli
C. Contraction of the external intercostal muscles
D. Diaphragmatic descent increasing intrathoracic pressure
Correct Answer: B
Rationale: During normal expiration, air leaves the lungs primarily through the elastic
recoil of alveoli and lung tissue, a passive process that asthma obstructs by narrowing
airways and trapping air. Passive chest wall recoil does contribute to expiration but is
not the primary driver of airflow out of the lungs. Understanding this mechanism helps
explain why bronchodilators are essential to reduce airway resistance and allow
alveolar recoil to empty the lungs effectively.
Question 3 of 50
A 24-year-old weightlifter complains of muscle fatigue during repeated heavy squats. A
biopsy reveals normal muscle fiber density but decreased ATP availability in the
fast-twitch fibers.
A. Release of calcium ions from the sarcoplasmic reticulum
B. Binding of myosin heads to actin binding sites
C. Detachment of myosin from actin and re-cocking of the myosin head
D. Propagation of the action potential along the T-tubule
Correct Answer: C
,Rationale: ATP is required to detach myosin heads from actin and return them to their
high-energy cocked position; without sufficient ATP, cross-bridges remain bound and the
muscle cannot relax or cycle efficiently. Calcium release and action potential
propagation are energy-independent processes that occur before cross-bridge cycling
begins. This explains why muscles become rigid and fatigued when ATP stores are
depleted during intense anaerobic exercise.
Question 4 of 50
A 55-year-old postmenopausal woman is found to have low bone density on a DEXA
scan. Her serum calcium is slightly below normal and parathyroid hormone levels are
elevated.
A. Osteoblasts to deposit new bone matrix
B. Chondrocytes to produce cartilaginous callus
C. Osteogenic stem cells to differentiate into osteoblasts
D. Osteoclasts to resorb bone and release calcium
Correct Answer: D
Rationale: Parathyroid hormone raises blood calcium levels primarily by stimulating
osteoclast activity, which breaks down bone matrix and releases stored calcium into
circulation. While PTH can indirectly influence osteoblasts, its acute effect on calcium
homeostasis is mediated through osteoclast-driven bone resorption. This is why
prolonged hyperparathyroidism leads to osteoporosis, as sustained osteoclast activity
weakens the skeletal framework over time.
Question 5 of 50
A 32-year-old patient with multiple sclerosis experiences blurred vision and numbness
in the extremities. An MRI reveals demyelination of neurons in the central nervous
system.
, A. Saltatory conduction of action potentials
B. Diffusion of neurotransmitters across the synaptic cleft
C. Active transport of sodium out of the axon terminal
D. Passive leakage of potassium through voltage-gated channels
Correct Answer: A
Rationale: Myelin sheaths insulate axons and allow action potentials to jump rapidly
between Nodes of Ranvier in a process called saltatory conduction; demyelination
slows or blocks this signal transmission. Neurotransmitter diffusion occurs at the
synapse and is not directly dependent on myelin integrity. This explains why
remyelination therapies are a major target in multiple sclerosis treatment, as restoring
saltatory conduction can improve neurological function.
Question 6 of 50
A 45-year-old patient with chronic pancreatitis reports steatorrhea and weight loss
despite adequate caloric intake. Laboratory studies show decreased serum levels of
fat-soluble vitamins.
A. Bicarbonate ions to neutralize gastric acid
B. Lipase to enzymatically digest triglycerides
C. Amylase to break down complex carbohydrates
D. Mucus to protect the duodenal mucosa
Correct Answer: B
Rationale: Pancreatic lipase is the primary enzyme responsible for breaking down
dietary triglycerides into absorbable fatty acids and monoglycerides in the small
intestine. Bicarbonate deficiency would affect pH regulation and indirectly impair
enzyme function but is not the direct cause of fat malabsorption. Patients with
pancreatic insufficiency require oral enzyme replacement therapy containing lipase to
restore normal fat digestion and prevent nutritional deficiencies.
Question 7 of 50
Actual Exam Complete Questions and Answers
Detailed Rationales Pass Guaranteed - A+ Graded
TABLE OF CONTENTS
Section 1 | Human Anatomy and Physiology | Q1 – Q10
Section 2 | Biology and Life Sciences | Q11 – Q20
Section 3 | Chemistry and Chemical Reactions | Q21 – Q30
Section 4 | Scientific Measurement and Data Interpretation | Q31 – Q40
Section 5 | Scientific Reasoning and Problem Solving | Q41 – Q50
Instructions: Choose the single best answer. Pass: 80% in 90 minutes.
══════════════════════════════════════
SECTION 1: HUMAN ANATOMY AND PHYSIOLOGY Q1 – Q10
══════════════════════════════════════
Question 1 of 50
A 68-year-old male patient arrives at the emergency department complaining of
crushing chest pain radiating to his left arm. His blood pressure is 180/110 mmHg and
an ECG shows ST-segment elevation.
A. Increased cardiac output and peripheral vascular resistance
B. Decreased venous return to the right atrium
C. Reduced sensitivity of baroreceptor reflexes
D. Excessive parasympathetic stimulation of the sinoatrial node
Correct Answer: A
Rationale: Systemic blood pressure is determined primarily by cardiac output and total
peripheral resistance, so an acute hypertensive episode in a cardiac event reflects
increased cardiac workload and vasoconstriction. Decreased venous return would
typically lower preload and reduce cardiac output rather than raise blood pressure. In
,clinical practice, managing both cardiac output and vascular resistance is essential
when treating hypertensive emergencies.
Question 2 of 50
A 7-year-old child with asthma is brought to the clinic during a mild exacerbation. The
provider notes bilateral wheezing and a prolonged expiratory phase on auscultation.
A. Passive recoil of the chest wall during inspiration
B. Expiration driven by elastic recoil of the alveoli
C. Contraction of the external intercostal muscles
D. Diaphragmatic descent increasing intrathoracic pressure
Correct Answer: B
Rationale: During normal expiration, air leaves the lungs primarily through the elastic
recoil of alveoli and lung tissue, a passive process that asthma obstructs by narrowing
airways and trapping air. Passive chest wall recoil does contribute to expiration but is
not the primary driver of airflow out of the lungs. Understanding this mechanism helps
explain why bronchodilators are essential to reduce airway resistance and allow
alveolar recoil to empty the lungs effectively.
Question 3 of 50
A 24-year-old weightlifter complains of muscle fatigue during repeated heavy squats. A
biopsy reveals normal muscle fiber density but decreased ATP availability in the
fast-twitch fibers.
A. Release of calcium ions from the sarcoplasmic reticulum
B. Binding of myosin heads to actin binding sites
C. Detachment of myosin from actin and re-cocking of the myosin head
D. Propagation of the action potential along the T-tubule
Correct Answer: C
,Rationale: ATP is required to detach myosin heads from actin and return them to their
high-energy cocked position; without sufficient ATP, cross-bridges remain bound and the
muscle cannot relax or cycle efficiently. Calcium release and action potential
propagation are energy-independent processes that occur before cross-bridge cycling
begins. This explains why muscles become rigid and fatigued when ATP stores are
depleted during intense anaerobic exercise.
Question 4 of 50
A 55-year-old postmenopausal woman is found to have low bone density on a DEXA
scan. Her serum calcium is slightly below normal and parathyroid hormone levels are
elevated.
A. Osteoblasts to deposit new bone matrix
B. Chondrocytes to produce cartilaginous callus
C. Osteogenic stem cells to differentiate into osteoblasts
D. Osteoclasts to resorb bone and release calcium
Correct Answer: D
Rationale: Parathyroid hormone raises blood calcium levels primarily by stimulating
osteoclast activity, which breaks down bone matrix and releases stored calcium into
circulation. While PTH can indirectly influence osteoblasts, its acute effect on calcium
homeostasis is mediated through osteoclast-driven bone resorption. This is why
prolonged hyperparathyroidism leads to osteoporosis, as sustained osteoclast activity
weakens the skeletal framework over time.
Question 5 of 50
A 32-year-old patient with multiple sclerosis experiences blurred vision and numbness
in the extremities. An MRI reveals demyelination of neurons in the central nervous
system.
, A. Saltatory conduction of action potentials
B. Diffusion of neurotransmitters across the synaptic cleft
C. Active transport of sodium out of the axon terminal
D. Passive leakage of potassium through voltage-gated channels
Correct Answer: A
Rationale: Myelin sheaths insulate axons and allow action potentials to jump rapidly
between Nodes of Ranvier in a process called saltatory conduction; demyelination
slows or blocks this signal transmission. Neurotransmitter diffusion occurs at the
synapse and is not directly dependent on myelin integrity. This explains why
remyelination therapies are a major target in multiple sclerosis treatment, as restoring
saltatory conduction can improve neurological function.
Question 6 of 50
A 45-year-old patient with chronic pancreatitis reports steatorrhea and weight loss
despite adequate caloric intake. Laboratory studies show decreased serum levels of
fat-soluble vitamins.
A. Bicarbonate ions to neutralize gastric acid
B. Lipase to enzymatically digest triglycerides
C. Amylase to break down complex carbohydrates
D. Mucus to protect the duodenal mucosa
Correct Answer: B
Rationale: Pancreatic lipase is the primary enzyme responsible for breaking down
dietary triglycerides into absorbable fatty acids and monoglycerides in the small
intestine. Bicarbonate deficiency would affect pH regulation and indirectly impair
enzyme function but is not the direct cause of fat malabsorption. Patients with
pancreatic insufficiency require oral enzyme replacement therapy containing lipase to
restore normal fat digestion and prevent nutritional deficiencies.
Question 7 of 50
