BIOL 2457 Exam 2 2026 Questions with
Complete Solutions & Detailed Rationales
SECTION 1: MUSCLE ANATOMY & FUNCTION (Questions 1–25)
Question 1
What muscle pulls the scapula forward and downwards?
A. Pectoralis major
B. Serratus anterior
C. Trapezius
D. Rhomboid major
E. Latissimus dorsi
Correct Answer: A. Pectoralis major
Rationale: The pectoralis major pulls the scapula forward and downwards. This
muscle originates on the sternum and clavicle and inserts on the humerus,
facilitating forward movement of the scapula.
Question 2
What muscle pulls the scapula upwards and rotates it laterally?
A. Pectoralis major
B. Serratus anterior
C. Trapezius
D. Rhomboid major
E. Latissimus dorsi
Correct Answer: B. Serratus anterior
Rationale: The serratus anterior pulls the scapula upwards and rotates it laterally.
This muscle is located on the lateral chest wall and is responsible for protraction
and upward rotation of the scapula.
,Question 3
What is the prime adductor of the arm?
A. Pectoralis major
B. Deltoid
C. Latissimus dorsi
D. Teres major
E. Coracobrachialis
Correct Answer: A. Pectoralis major
Rationale: The pectoralis major is the prime adductor of the arm. It acts to bring
the arm toward the midline of the body.
Question 4
What muscle medially rotates the arms?
A. Pectoralis major
B. Deltoid
C. Supraspinatus
D. Infraspinatus
E. Teres minor
Correct Answer: A. Pectoralis major
Rationale: The pectoralis major medially rotates the arms. This action helps bring
the arm inward toward the body.
Question 5
What is the role of the external intercostal muscles?
A. Depress ribs for expiration
B. Increase thoracic volume for inhalation
C. Compress the abdomen
D. Rotate the spine
E. Flex the vertebral column
Correct Answer: B. Increase thoracic volume for inhalation
,Rationale: The external intercostal muscles elevate the ribs and increase thoracic
volume during inhalation (inspiration).
Question 6
What does the internal intercostal muscle do?
A. Elevates ribs for inhalation
B. Depresses ribs for expiration
C. Rotates the scapula
D. Flexes the spine
E. Extends the spine
Correct Answer: B. Depresses ribs for expiration
Rationale: The internal intercostal muscles depress the ribs, decreasing thoracic
volume during forced expiration.
Question 7
What is the diaphragm?
A. A muscle that elevates the ribs
B. A dome-shaped muscle under the lungs that is the primary muscle of inspiration
C. A muscle that rotates the scapula
D. A muscle that flexes the spine
E. A muscle that extends the spine
Correct Answer: B. A dome-shaped muscle under the lungs that is the
primary muscle of inspiration
Rationale: The diaphragm is a dome-shaped muscle located under the lungs that is
the primary muscle of inspiration (breathing in).
Question 8
What are the muscles of mastication?
A. Masseter, temporalis, buccinator, lateral pterygoid
B. Masseter, temporalis, sternocleidomastoid, trapezius
C. Buccinator, orbicularis oris, temporalis, masseter
, D. Masseter, pterygoid, buccinator, digastric
E. Temporalis, masseter, zygomaticus, buccinator
Correct Answer: A. Masseter, temporalis, buccinator, lateral pterygoid
Rationale: The muscles of mastication include the masseter, temporalis,
buccinator, and lateral pterygoid. These muscles work together to enable chewing.
Question 9
What is the role of the masseter?
A. Elevates the mandible
B. Depresses the mandible
C. Protracts the mandible
D. Retracts the mandible
E. Rotates the mandible
Correct Answer: A. Elevates the mandible
Rationale: The masseter elevates the mandible (closes the jaw) and is one of the
strongest muscles in the body.
Question 10
What does the temporalis muscle do?
A. Depresses the mandible
B. Elevates and retracts the mandible
C. Protracts the mandible
D. Rotates the mandible
E. Closes the lips
Correct Answer: B. Elevates and retracts the mandible
Rationale: The temporalis elevates and retracts the mandible, helping to close the
jaw and pull it backward.
Question 11
What does the orbicularis oris do?
Complete Solutions & Detailed Rationales
SECTION 1: MUSCLE ANATOMY & FUNCTION (Questions 1–25)
Question 1
What muscle pulls the scapula forward and downwards?
A. Pectoralis major
B. Serratus anterior
C. Trapezius
D. Rhomboid major
E. Latissimus dorsi
Correct Answer: A. Pectoralis major
Rationale: The pectoralis major pulls the scapula forward and downwards. This
muscle originates on the sternum and clavicle and inserts on the humerus,
facilitating forward movement of the scapula.
Question 2
What muscle pulls the scapula upwards and rotates it laterally?
A. Pectoralis major
B. Serratus anterior
C. Trapezius
D. Rhomboid major
E. Latissimus dorsi
Correct Answer: B. Serratus anterior
Rationale: The serratus anterior pulls the scapula upwards and rotates it laterally.
This muscle is located on the lateral chest wall and is responsible for protraction
and upward rotation of the scapula.
,Question 3
What is the prime adductor of the arm?
A. Pectoralis major
B. Deltoid
C. Latissimus dorsi
D. Teres major
E. Coracobrachialis
Correct Answer: A. Pectoralis major
Rationale: The pectoralis major is the prime adductor of the arm. It acts to bring
the arm toward the midline of the body.
Question 4
What muscle medially rotates the arms?
A. Pectoralis major
B. Deltoid
C. Supraspinatus
D. Infraspinatus
E. Teres minor
Correct Answer: A. Pectoralis major
Rationale: The pectoralis major medially rotates the arms. This action helps bring
the arm inward toward the body.
Question 5
What is the role of the external intercostal muscles?
A. Depress ribs for expiration
B. Increase thoracic volume for inhalation
C. Compress the abdomen
D. Rotate the spine
E. Flex the vertebral column
Correct Answer: B. Increase thoracic volume for inhalation
,Rationale: The external intercostal muscles elevate the ribs and increase thoracic
volume during inhalation (inspiration).
Question 6
What does the internal intercostal muscle do?
A. Elevates ribs for inhalation
B. Depresses ribs for expiration
C. Rotates the scapula
D. Flexes the spine
E. Extends the spine
Correct Answer: B. Depresses ribs for expiration
Rationale: The internal intercostal muscles depress the ribs, decreasing thoracic
volume during forced expiration.
Question 7
What is the diaphragm?
A. A muscle that elevates the ribs
B. A dome-shaped muscle under the lungs that is the primary muscle of inspiration
C. A muscle that rotates the scapula
D. A muscle that flexes the spine
E. A muscle that extends the spine
Correct Answer: B. A dome-shaped muscle under the lungs that is the
primary muscle of inspiration
Rationale: The diaphragm is a dome-shaped muscle located under the lungs that is
the primary muscle of inspiration (breathing in).
Question 8
What are the muscles of mastication?
A. Masseter, temporalis, buccinator, lateral pterygoid
B. Masseter, temporalis, sternocleidomastoid, trapezius
C. Buccinator, orbicularis oris, temporalis, masseter
, D. Masseter, pterygoid, buccinator, digastric
E. Temporalis, masseter, zygomaticus, buccinator
Correct Answer: A. Masseter, temporalis, buccinator, lateral pterygoid
Rationale: The muscles of mastication include the masseter, temporalis,
buccinator, and lateral pterygoid. These muscles work together to enable chewing.
Question 9
What is the role of the masseter?
A. Elevates the mandible
B. Depresses the mandible
C. Protracts the mandible
D. Retracts the mandible
E. Rotates the mandible
Correct Answer: A. Elevates the mandible
Rationale: The masseter elevates the mandible (closes the jaw) and is one of the
strongest muscles in the body.
Question 10
What does the temporalis muscle do?
A. Depresses the mandible
B. Elevates and retracts the mandible
C. Protracts the mandible
D. Rotates the mandible
E. Closes the lips
Correct Answer: B. Elevates and retracts the mandible
Rationale: The temporalis elevates and retracts the mandible, helping to close the
jaw and pull it backward.
Question 11
What does the orbicularis oris do?
