Chapter 11 - Muscular System Flashcards
(30 cards)
Which of the following helps an agonist work?
A) A synergist.
B) A fixator.
C) An insertion.
D) An antagonist.
A) A synergist.
Explanation: Synergists assist the agonist by adding force or stabilizing nearby joints, improving movement efficiency.
Incorrect Answers:
B) A fixator. Stabilizes the origin, but doesn’t help perform the movement itself.
C) An insertion. A physical attachment point, not a helper.
D) An antagonist. Produces the opposite action of the agonist.
Which of the following statements is correct about what happens during flexion?
A) The angle between bones is increased.
B) The angle between bones is decreased.
C) The bone moves away from the body.
D) The bone moves toward the center of the body.
B) The angle between bones is decreased.
Explanation: Flexion bends a joint, reducing the angle between the articulating bones (e.g., bending the elbow).
Incorrect Answers:
A) Increased angle. Describes extension.
C) Moves away from body. Describes abduction.
D) Toward the center. Not specific enough—many movements do this.
Which is moved the least during muscle contraction?
A) The origin.
B) The insertion.
C) The ligaments.
D) The joints.
A) The origin.
Explanation: The origin is the fixed attachment point; muscles pull toward it during contraction.
Incorrect Answers:
B) The insertion. Moves toward the origin.
C) The ligaments. Are passive stabilizers, not actively moved.
D) The joints. Move as muscles act across them.
Which muscle has a convergent pattern of fascicles?
A) Biceps brachii.
B) Gluteus maximus.
C) Pectoralis major.
D) Rectus femoris.
C) Pectoralis major.
Explanation: Its fibers spread out broadly and converge on a single tendon—classic convergent pattern.
Incorrect Answers:
A) Biceps brachii. Has a fusiform shape (parallel with thick belly).
B) Gluteus maximus. Has a roughly parallel fiber layout.
D) Rectus femoris. Is bipennate—fibers insert from both sides.
A muscle that has a pattern of fascicles running along the long axis of the muscle has which of the following fascicle arrangements?
A) Circular.
B) Pennate.
C) Parallel.
D) Rectus.
C) Parallel.
Explanation: In parallel muscles, fibers run alongside the muscle’s length, allowing greater shortening and range of motion.
Incorrect Answers:
A) Circular. Fibers surround openings (e.g., mouth, eye).
B) Pennate. Fibers insert at angles to a central tendon.
D) Rectus. Refers to fiber direction (“straight”), not arrangement.
Which arrangement best describes a bipennate muscle?
A) The muscle fibers feed in on an angle to a long tendon from both sides.
B) The muscle fibers feed in on an angle to a long tendon from all directions.
C) The muscle fibers feed in on an angle to a long tendon from one side.
D) The muscle fibers on one side of a tendon feed into it at a certain angle and muscle fibers on the other side of the tendon feed into it at the opposite angle.
A) The muscle fibers feed in on an angle to a long tendon from both sides.
Explanation: This arrangement looks like a feather and allows for greater force production.
Incorrect Answers:
B) From all directions. Describes multipennate, not bipennate.
C) From one side. Describes unipennate.
D) Opposite angles. Overcomplicates a simple two-sided insertion.
The location of a muscle’s insertion and origin can determine (BLANK).
A) Action.
B) The force of contraction.
C) Muscle name.
D) The load a muscle can carry.
A) Action.
Explanation: Where a muscle attaches affects how and in what direction it moves bones.
Incorrect Answers:
B) Force of contraction. Determined by muscle size and fiber type.
C) Muscle name. May reflect attachments, but not always.
D) Load capacity. Depends on leverage and fiber structure
Which muscle name does not make sense?
A) Extensor digitorum.
B) Gluteus minimus.
C) Biceps femoris.
D) Extensor minimus longus.
D) Extensor minimus longus.
Explanation: “Minimus” means small; “longus” means long. Using both is contradictory and not used in anatomical naming.
Incorrect Answers:
A) Extensor digitorum. Accurately describes a finger-extending muscle.
B) Gluteus minimus. The smallest of the gluteal muscles.
C) Biceps femoris. Two-headed muscle on the posterior thigh.
Which of the following terms would be used in the name of a muscle that moves the leg away from the body?
A) Flexor.
B) Adductor.
C) Extensor.
D) Abductor.
D) Abductor.
Explanation: Abductors move limbs away from the body’s midline (like raising your arm sideways).
Incorrect Answers:
A) Flexor. Decreases joint angle—not related to direction.
B) Adductor. Brings limbs toward the midline.
C) Extensor. Straightens a joint, not necessarily directional.
The names of the extrinsic tongue muscles commonly end in (BLANK).
A) -Glottis.
B) -Glossus.
C) -Gluteus.
D) -Hyoid.
B) -Glossus.
Explanation: Extrinsic tongue muscles (e.g., genioglossus, hyoglossus) end in “-glossus,” referencing the tongue.
Incorrect Answers:
A) -Glottis. Part of the larynx.
C) -Gluteus. Buttock muscles.
D) -Hyoid. A bone associated with tongue movement, but not used in naming tongue muscles.
Anatomists name the skeletal muscles according to a number of criteria such as (BLANK).
A) Number of origins or its action.
B) Shape.
C) Location.
D) All of these.
D) All of these.
Muscle names often reflect multiple characteristics, including number of origins (e.g., biceps), action (e.g., flexor), shape (e.g., deltoid), and location (e.g., temporalis).
Incorrect Answers:
A) Number of origins or its action. This is true but incomplete.
B) Shape. Also valid but only one naming criterion.
C) Location. Correct but not the full scope of naming conventions.
Which of the following is unique to the muscles of facial expression?
A) They all originate from the scalp musculature.
B) They insert onto the cartilage found around the face.
C) They only insert onto the facial bones.
D) They insert into the skin.
D) They insert into the skin.
Explanation: Facial muscles move the skin directly, enabling expressions like smiling or frowning.
Incorrect Answers:
A) Originate from scalp. Only some do (e.g., occipitofrontalis).
B) Insert onto cartilage. Rare for facial muscles.
C) Insert on facial bones. They originate there but don’t typically insert there.
Where is the temporalis muscle located?
A) On the forehead.
B) In the neck.
C) On the side of the head.
D) On the chin.
C) On the side of the head.
Explanation: The temporalis covers the temporal bone and elevates the mandible during chewing.
Incorrect Answers:
A) On the forehead. That’s frontalis.
B) In the neck. Muscles like sternocleidomastoid are located there.
D) On the chin. Likely refers to the mentalis.
Which of the following is a prime mover in head flexion?
A) Occipitofrontalis.
B) Corrugator supercilii.
C) Sternocleidomastoid.
D) Masseter.
C) Sternocleidomastoid.
Explanation: This muscle pulls the head forward and downward when both sides contract.
Incorrect Answers:
A) Occipitofrontalis. Moves scalp and eyebrows.
B) Corrugator supercilii. Controls eyebrow movement.
D) Masseter. Involved in jaw elevation, not neck motion.
Where is the inferior oblique muscle located?
A) In the abdomen.
B) In the eye socket.
C) In the anterior neck.
D) In the face.
B) In the eye socket.
Explanation: The inferior oblique rotates the eye upward and laterally; located within the orbit.
Incorrect Answers:
A) Abdomen. Has internal and external obliques, not “inferior.”
C) Anterior neck. No muscle with this name there.
D) Face. Facial expression muscles don’t include this.
What is the function of the erector spinae?
A) Movement of the arms.
B) Stabilization of the pelvic girdle.
C) Postural support.
D) Rotating of the vertebral column.
C) Postural support.
Explanation: The erector spinae group maintains upright posture and extends the vertebral column.
Incorrect Answers:
A) Movement of the arms. Controlled by shoulder and upper limb muscles.
B) Stabilization of the pelvic girdle. Done by deeper pelvic and core muscles.
D) Rotating of the vertebral column. Primarily done by muscles like the transversospinales.
What is the action of the masseter?
A) Swallowing.
B) Chewing.
C) Moving the lips.
D) Closing the eye.
B) Chewing.
Explanation: The masseter is the primary muscle for elevating the jaw during mastication.
Incorrect Answers:
A) Swallowing. Controlled by pharyngeal muscles.
C) Moving lips. Done by orbicularis oris and others.
D) Closing eye. Orbicularis oculi does this.
Which muscle pair plays a role in respiration?
A) Intertransversarii, interspinales.
B) Semispinalis cervicis, semispinalis thoracis.
C) Trapezius, rhomboids.
D) Diaphragm, scalene.
D) Diaphragm, scalene.
Explanation: The diaphragm is the main muscle of respiration; the scalenes assist by elevating the first two ribs during inhalation.
Incorrect Answers:
A) Intertransversarii, interspinales. Stabilize the vertebrae, not respiratory muscles.
B) Semispinalis group. Involved in extending and rotating the spine.
C) Trapezius, rhomboids. Move the scapula, not involved in breathing.
The rhomboid major and minor muscles are deep to the (BLANK).
A) Rectus abdominis.
B) Scalene muscles.
C) Trapezius.
D) Ligamentum nuchae.
C) Trapezius.
Explanation: The rhomboids lie beneath the trapezius and help retract the scapula.
Incorrect Answers:
A) Rectus abdominis. Located in the anterior abdomen, unrelated.
B) Scalene muscles. Found in the neck, not directly over the rhomboids.
D) Ligamentum nuchae. A cervical ligament, not a muscle covering
What is another term for swallowing?
A) Axialate.
B) Glutination.
C) Deglutition.
D) Mastigation.
C) Deglutition.
Explanation: Deglutition is the scientific term for swallowing—the process of moving food from the mouth to the stomach.
Incorrect Answers:
A) Axialate. Not a real anatomical term.
B) Glutination. Not used in human physiology; may be a misinterpretation of “agglutination.”
D) Mastigation. Incorrect form; the correct term for chewing is mastication.
Which of the following abdominal muscles is not a part of the anterior abdominal wall?
A) Quadratus lumborum.
B) Rectus abdominis.
C) Interior oblique.
D) Exterior oblique.
A) Quadratus lumborum.
Explanation: This muscle is part of the posterior abdominal wall and helps laterally flex the spine.
Incorrect Answers:
B) Rectus abdominis. Main vertical muscle of the anterior abdominal wall.
C) Interior oblique. Lies beneath the external oblique in the front.
D) Exterior oblique. Outermost abdominal wall muscle in front.
What is the linea alba?
A) A small muscle that helps with compression of the abdominal organs.
B) A long tendon that runs down the middle of the rectus abdominis.
C) A long band of collagen fibers that connects the hip to the knee.
D) Another name for the tendinous inscription.
B) A long tendon that runs down the middle of the rectus abdominis.
Explanation: The linea alba is a fibrous midline structure where the abdominal muscles meet.
Incorrect Answers:
A) A small muscle. It is connective tissue, not muscle.
C) Connects hip to knee. Describes the iliotibial band, not linea alba.
D) Tendinous inscription. These are horizontal divisions within the rectus abdominis.
Which muscle extends the forearm?
A) Biceps brachii.
B) Triceps brachii.
C) Brachialis.
D) Deltoid.
B) Triceps brachii.
Explanation: The triceps is the primary extensor of the elbow joint.
Incorrect Answers:
A) Biceps brachii. Flexes the forearm and supinates the hand.
C) Brachialis. Also flexes the elbow.
D) Deltoid. Abducts the arm at the shoulder.
What is the origin of the wrist flexors?
A) The lateral epicondyle of the humerus.
B) The medial epicondyle of the humerus.
C) The carpal bones of the wrist.
D) The deltoid tuberosity of the humerus.
B) The medial epicondyle of the humerus.
Explanation: Most wrist flexors originate on the medial epicondyle, a common flexor origin.
Incorrect Answers:
A) Lateral epicondyle. Origin of the wrist extensors.
C) Carpal bones. Insertion points, not origins.
D) Deltoid tuberosity. Insertion of the deltoid muscle.
