ATI TEAS 7 Science Practice Exam II
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
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1. Which organelle is the primary site of adenosine triphosphate (ATP)
production via oxidative phosphorylation?
A) Ribosome
B) Golgi apparatus
C) Mitochondrion
D) Lysosome
C) Mitochondrion
The inner mitochondrial membrane houses the electron transport chain and
ATP synthase, coupling the oxidation of NADH and FADH₂ to the
phosphorylation of ADP, generating the majority of cellular ATP.
2. The pulmonary artery transports blood from the right ventricle to the lungs.
What type of blood does it carry?
A) Oxygenated blood
B) Deoxygenated blood
C) Mixed oxygenated and deoxygenated blood
D) Nutrient-rich blood
B) Deoxygenated blood
The pulmonary artery is the only artery that carries deoxygenated blood,
moving it to the pulmonary capillaries where gas exchange oxygenates the
blood.
3. Which layer of the skin contains blood vessels, nerve endings, and hair
follicles?
A) Epidermis
, B) Dermis
C) Hypodermis
D) Stratum corneum
B) Dermis
The dermis is the middle layer of the skin, rich in connective tissue, blood
vessels, sensory receptors, and appendages such as hair follicles and glands.
4. In a neuron at rest, the intracellular concentration of which ion is higher than
the extracellular concentration, contributing to the resting membrane
potential?
A) Sodium (Na⁺)
B) Chloride (Cl⁻)
C) Potassium (K⁺)
D) Calcium (Ca²⁺)
C) Potassium (K⁺)
Resting neurons maintain a high internal K⁺ concentration due to Na⁺/K⁺-
ATPase pumps, and leak channels allow K⁺ efflux, making the interior
negative relative to the outside.
5. What is the role of the enzyme helicase in DNA replication?
A) Adding RNA primers
B) Unwinding the double helix
C) Joining Okazaki fragments
D) Synthesizing new DNA strands
B) Unwinding the double helix
Helicase breaks the hydrogen bonds between complementary bases,
separating the two strands to form the replication fork, allowing each strand
to serve as a template.
6. A researcher manipulates the amount of light in a growth chamber to study
its effect on plant height. Which variable is the independent variable?
A) Plant species
B) Growth chamber temperature
C) Amount of light
, D) Plant height
C) Amount of light
The independent variable is the factor intentionally changed (light amount);
plant height is the dependent variable measured in response.
7. Which of the following is a function of the large intestine?
A) Secretion of digestive enzymes
B) Absorption of amino acids
C) Water and electrolyte reabsorption
D) Emulsification of fats
C) Water and electrolyte reabsorption
The large intestine absorbs water, sodium, and other electrolytes from
indigestible food matter, forming solid feces for elimination.
8. In the cardiac cycle, what does the QRS complex on an electrocardiogram
represent?
A) Atrial depolarization
B) Ventricular repolarization
C) Ventricular depolarization
D) Atrial repolarization
C) Ventricular depolarization
The QRS complex corresponds to depolarization of the ventricles, which
triggers ventricular contraction (systole). Atrial repolarization is masked by
this larger electrical event.
9. Which gland secretes melatonin, regulating the sleep-wake cycle?
A) Pituitary gland
B) Pineal gland
C) Thyroid gland
D) Adrenal gland
B) Pineal gland
The pineal gland produces melatonin in response to darkness, helping to
synchronize circadian rhythms and sleep patterns.
Questions And Correct Answers (Verified
Answers) Plus Rationales 2026 Q&A |
Instant Download Pdf
1. Which organelle is the primary site of adenosine triphosphate (ATP)
production via oxidative phosphorylation?
A) Ribosome
B) Golgi apparatus
C) Mitochondrion
D) Lysosome
C) Mitochondrion
The inner mitochondrial membrane houses the electron transport chain and
ATP synthase, coupling the oxidation of NADH and FADH₂ to the
phosphorylation of ADP, generating the majority of cellular ATP.
2. The pulmonary artery transports blood from the right ventricle to the lungs.
What type of blood does it carry?
A) Oxygenated blood
B) Deoxygenated blood
C) Mixed oxygenated and deoxygenated blood
D) Nutrient-rich blood
B) Deoxygenated blood
The pulmonary artery is the only artery that carries deoxygenated blood,
moving it to the pulmonary capillaries where gas exchange oxygenates the
blood.
3. Which layer of the skin contains blood vessels, nerve endings, and hair
follicles?
A) Epidermis
, B) Dermis
C) Hypodermis
D) Stratum corneum
B) Dermis
The dermis is the middle layer of the skin, rich in connective tissue, blood
vessels, sensory receptors, and appendages such as hair follicles and glands.
4. In a neuron at rest, the intracellular concentration of which ion is higher than
the extracellular concentration, contributing to the resting membrane
potential?
A) Sodium (Na⁺)
B) Chloride (Cl⁻)
C) Potassium (K⁺)
D) Calcium (Ca²⁺)
C) Potassium (K⁺)
Resting neurons maintain a high internal K⁺ concentration due to Na⁺/K⁺-
ATPase pumps, and leak channels allow K⁺ efflux, making the interior
negative relative to the outside.
5. What is the role of the enzyme helicase in DNA replication?
A) Adding RNA primers
B) Unwinding the double helix
C) Joining Okazaki fragments
D) Synthesizing new DNA strands
B) Unwinding the double helix
Helicase breaks the hydrogen bonds between complementary bases,
separating the two strands to form the replication fork, allowing each strand
to serve as a template.
6. A researcher manipulates the amount of light in a growth chamber to study
its effect on plant height. Which variable is the independent variable?
A) Plant species
B) Growth chamber temperature
C) Amount of light
, D) Plant height
C) Amount of light
The independent variable is the factor intentionally changed (light amount);
plant height is the dependent variable measured in response.
7. Which of the following is a function of the large intestine?
A) Secretion of digestive enzymes
B) Absorption of amino acids
C) Water and electrolyte reabsorption
D) Emulsification of fats
C) Water and electrolyte reabsorption
The large intestine absorbs water, sodium, and other electrolytes from
indigestible food matter, forming solid feces for elimination.
8. In the cardiac cycle, what does the QRS complex on an electrocardiogram
represent?
A) Atrial depolarization
B) Ventricular repolarization
C) Ventricular depolarization
D) Atrial repolarization
C) Ventricular depolarization
The QRS complex corresponds to depolarization of the ventricles, which
triggers ventricular contraction (systole). Atrial repolarization is masked by
this larger electrical event.
9. Which gland secretes melatonin, regulating the sleep-wake cycle?
A) Pituitary gland
B) Pineal gland
C) Thyroid gland
D) Adrenal gland
B) Pineal gland
The pineal gland produces melatonin in response to darkness, helping to
synchronize circadian rhythms and sleep patterns.
