Lab Exam #3
Which of the following muscles is NOT a muscle of the abdominal wall?
Internal intercostal
Which muscle(s) of the pelvic floor is/are responsible for erection of the penis and clitoris?
Bulbospongiosus and ischiocavernosus
Which of the following is NOT true of the masseter muscle?
It is innervated by the facial nerve.
A particular muscle causes flexion of the lower limb at the knee. It is located on the posterior side of the thigh. Where would you expect to find its antagonist?
On the anterior side of the thigh
Which of the following muscles is located on the anterior side of the scapula?
Subscapularis
Which of the following is NOT true of the hamstring group of muscles?
All of the hamstrings insert on both the tibia and the fibula.
Which of the following muscles of facial expression inserts on the orbicularis oris, and compresses the cheeks when blowing air?
Buccinator
Compared to the forearm, the leg has a greater number of muscles.
False
From your study of images of the lower limb muscles, what is a retinaculum?
A band of connective tissue that holds a group of tendons in place
The origins of the muscles that move the foot are on the femur, tibia, or fibula.
True
Which of the abdominal wall muscles help(s) flex the vertebral column?
Rectus abdominis
All of the major adductors of the thigh have origins on the
Pubis
Thigh muscles that attach to the medial side of the pelvis __________ the thigh at the hip joint.
Adduct
Which of the following is NOT true of a myofibril?
Myofibrils are composed of muscle fibers.
The human hand has a unique ability for grasping objects, writing, and drawing, due to opposition of the thumb.
True
The rotator cuff muscles all have insertions on the greater and lesser tubercles of the humerus.
True
Which of the following muscles of the head and neck elevate(s) ribs 1 and 2, and flex(es) and rotate(s) the neck when the first rib is flexed?
Scalenes
Muscles that move the leg at the knee joint have origins on the
femur or hip bone
The connective tissue layer that surrounds each bundle of muscle fibers is called the
Perimysium
Many of the flexors of the wrist and fingers originate on the
medial epicondyle of the humerus
Which of the following is NOT a method of naming muscles?
All of these are methods of naming muscles.
The flexor carpi radialis and flexor carpi ulnaris both flex the wrist and abduct the hand.
False
The boundary between adjacent sarcomeres is the
Z line (disc)
Due to its name and position in the forearm (posterior medial side of the forearm), the actions of the extensor carpi ulnaris are most likely to
extend the wrist and adduct the hand.
Whenever an object is lifted, all motor units in the appropriate muscle(s) are stimulated, regardless of the weight of the object.
False
Which of the following facial muscles stretches from the lower portion of the mandible to the fascia of the upper chest, and pulls the angle of the mouth downward during pouting or expression of horror?
Platysma
Which of the following facial muscles raise(s) the corners of the mouth for smiling and laughing?
Zygomaticus major and minor
Which of the following is NOT a muscle of respiration?
Pectoralis major
The gluteus maximus, medius, and minimus muscles all have the same action (extension of the thigh at the hip).
False
Which of the following organelles stores calcium in skeletal muscle fibers for contraction?
Sarcoplasmic reticulum
Which region of a sarcomere contains thick filaments overlapping with thin filaments?
A band
The muscles of the lower limb have a more limited range of motion than those of the upper limb.
True
Which of the following does NOT occur as a sarcomere shortens during muscle contraction?
The thin and thick myofilaments shorten in length.
Muscles in the forearm that move the hand have insertions on the
carpals, metacarpals, or phalanges.
In general, the extensors of the wrist and fingers are located on the anterior side of the forearm.
False
The deep muscles of the back flex the vertebral column.
False
The muscles that move the head are found in the neck.
True
Which of the following muscles associated with the vertebral column is the most superior?
Splenius capitis
Which of the following is the only muscle of mastication that depresses and protracts the mandible?
Lateral pterygoid
Which of the following muscles that move(s) the pectoral girdle retract(s) and elevate(s) the scapula?
Rhomboid major and minor
The group of muscles that moves the hyoid bone and larynx helps with the processes of speech and swallowing.
True
A skeletal muscle is considered to be an organ of the muscular system.
True
Which muscle of the pelvic floor acts as a sphincter in the vagina and anal canal?
Levator ani
What is a fascicle of a skeletal muscle?
A bundle of skeletal muscle fibers
Which of the following is NOT true of the biceps brachii muscle?
It inserts on the olecranon process of the ulna.
Which of the following muscles insert(s) on the patella?
Quadriceps femoris group
Which of the following muscle groups contains some muscles that are innervated by the ansa cervicalis?
Muscles that move the hyoid bone and larynx
Which of the following is NOT true of the diaphragm?
When it contracts, it compresses the thorax and decreases its volume.
Which of the following is NOT true of the epicranius muscle?
It is considered to be a muscle of mastication.
All muscles cross only one joint.
False
A muscle that runs down the arm, and inserts on the olecranon process of the ulna, would cause
extension of the elbow.
A sheet of connective tissue, which connects muscles (or parts of muscles) to other muscles (or their parts), is called a(n)
aponeurosis.
Why are the psoas major and the iliacus sometimes called the iliopsoas?
They join at their inferior ends and have the same insertion.
Which of the following muscles elevates the hyoid bone during the swallowing process?
Mylohyoid
The anterior portion of the perineum is called the
urogenital triangle
What is the function of medial and lateral excursion, movements of some of the muscles of mastication?
To move the mandible side to side, to help grind food
The linea alba is a muscle of the pelvic floor.
False
Where would you expect to find muscles that cause dorsiflexion of the foot?
Anterior side of the leg
In a motor unit, each neuron innervates (controls) a single muscle fiber.
False
Muscles that move the thigh at the hip joint have insertions on the
Femur
The muscles of mastication are all inserted on the maxilla.
False
The origin of a skeletal muscle is the attachment site at the less moveable/more stationary end.
True
Looking at the names of these muscles, which one would you expect to insert on the distal phalanges of toes 2–5?
Flexor digitorum longus
All of the muscles that move the hyoid bone and larynx are innervated by the facial nerve.
False
A muscle that contracts to assist the main muscle in performing a particular action is called a(n)
Synergist
The muscles of the pelvic floor are almost entirely innervated by the pudendal nerve.
True
Some of the muscles of the hip and lower limb cross more than one joint.
True
Which of the following muscles of the vertebral column are unique, in that they originate on the iliac crest?
Quadratus lumborum
Which of the following is NOT true of the gastrocnemius muscle?
Its functions in dorsiflexion of the foot.
Which of the following correctly lists the erector spinae muscles, from lateral to medial?
Iliocostalis group, longissimus group, spinalis group
Which of the following nerves innervates the muscles of mastication?
Trigeminal nerve
The diamond-shaped area between the lower limbs is called the perineum.
True
Which of the following muscles has its origin on the lateral epicondyle of the humerus and its insertion on the proximal phalanx of the 5th finger?
Extensor digiti minimi
Unilateral contraction of the muscles of the erector spinal group results in
lateral flexion of the trunk.
Which muscles form the pelvic diaphragm?
Levator ani and coccygeus
Which respiratory muscle(s) function(s) only during forced expiration?
Internal intercostals
What does "striated" mean, as it applies to skeletal muscle?
It means that the tissue appears striped, due to the repeating pattern of the A bands and I bands in the sarcomeres.
Which muscles form the outermost layer of the layered abdominal wall muscles?
External oblique
What is the correct anatomical description of the leg?
Knee to ankle
A muscle can serve as an agonist in one action and an antagonist in another action.
True
The synaptic knob of a neuromuscular junction is the portion of the muscle fiber that contains receptor sites for neurotransmitters.
False
Which of the following muscles of the head and neck originates on the sternum and clavicle, and inserts on the mastoid process?
Sternocleidomastoid
What is the role of tropomyosin in a sarcomere?
It blocks the active sites on actin filaments in relaxed muscle fibers.
Most of the muscles that move the forearm and hand are innervated by the __________ nerve(s).
median and radial
The correct anatomical description of the arm is the region from the
shoulder to the elbow.
Which of the following muscles of facial expression is the only one that closes the eye when blinking?
Orbicularis oculi
What is/are the action(s) of the anterior leg muscles?
Dorsiflexion of the foot and extension of the toes
All of the following are posterior leg muscles except the
extensor digitorum longus.
A muscle fiber is identical to a muscle cell.
True
The majority of muscles that move the arm have origins on the
scapula.
The quadriceps femoris group of muscles is innervated by the __________ nerve.
Femoral
Which of the pelvic floor muscles inserts only on the coccyx?
Levator ani
Which of the following muscles is NOT a flexor of the elbow?
Triceps brachii