Exam 3 Anatomy questions

You hear a sharp noise to your left causing you to shift your eyes in that direction. Which muscles were responsible for your glance?

Left eye - lateral rectus, right eye - medial rectus

In addition to the thin filaments in I bands, there are protein filaments called ____________ that play a role in muscle elasticity (act like springs).

Titin

On a muscle fiber, the two terminal cisternae and the centrally placed T-tubule form a structure called a ______________.

Triad

The frontal belly of the occipitofrontalis muscle causes what action?

Wrinkles the brow (forehead)

If you contract your right sternocleidomastoid muscle, what movement would you expect?

Your head would turn to the left.

A sarcomere is defined as the distance from one _____ to the next adjacent ____ . (The same answer fills in both spaces.)

Z disc

With increased age, skeletal muscles show

a decrease in the number of myofibrils.

The top sprinters probably have _______ proportion of slow muscle fibers in their leg muscles.

a lower

What is the letter associated with the dark bands in a sarcomere?

A

Which is a correct listing of the hierarchy of a skeletal muscle's components, beginning with the smallest? a: Fascicle b: Muscle fiber c: Myofibrils d: Skeletal muscle

c, b, a, d

The smallest sized member of a group of muscles may have ____________ as part of its name.

minimus

The vascular supply to slow muscle fibers is ______ the network of capillaries around fast muscle fibers.

more extensive than

When the force is applied between the resistance and the fulcrum, the result is a _____ lever.

third-class

A(n) _____________ is a muscle whose actions oppose those of the agonist.

antagonist

The type of muscle fibers that are striated, form Y-shaped branches, and have junctions called intercalated discs are

cardiac

A muscle whose name has "orbicularis" in it is _______ in appearance.

circular

The resistance to fatigue of fast fibers is ______ when compared to that of slow or intermediate fibers.

low

The most medial of the abdominal muscles are the _________ muscles.

rectus abdominis

The ending "glossus" on the name of a muscle refers to

the tongue

The deepest of the abdominal muscles are the _________ muscles.

transversus abdominis

The calcium ions involved in skeletal muscle contraction bind to a(n)______ subunit.

troponin

In which body region would you expect to find a muscle whose name includes the word "pollicis"?

Thumb

What is an aponeurosis?

A flat sheet of connective tissue used for muscle insertion

Skeletal muscle contraction requires large amounts of energy in the form of ___________ in order to complete the sequence of cyclic events that lead to sarcomere shortening.

ATP

Which is the neurotransmitter that causes the release of calcium ions and initiates the steps of skeletal muscle fiber contraction?

Acetylcholine

Which depresses the ribs?

All of the choices are correct

Collectively, these muscles support and position the head, vertebral column, and thoracic cage. They also control movements associated with respiration and form part of the floor of the pelvic cavity.

Axial muscles

There are four muscles of mastication. Select the exception.

Buccinator

During muscle contraction, myosin heads attach to actin and thereby form connections called ______________.

Crossbridges

When contracted, this muscle causes expansion of the thoracic cavity and increases pressure in the abdominopelvic cavity. Its insertion is on a central tendon.

Diaphragm

These muscles elevate the ribs and have their origin on the inferior border of the superior rib and their insertion on the superior border of the inferior rib.

External intercostals

Which muscle does not move the mandible?

Genioglossus

Which letter is associated with a zone that is more lightly shaded because only thick filaments are present?

H

The more moveable attachment of a muscle is called its _______________.

Insertion

Which muscles arise from the skull and often attach to the skin?

Muscles of facial expression

Which muscles help us in the initial breakdown of food?

Muscles of mastication

These muscles extend from the pubis and ischium anteriorly to the sacrum and coccyx posteriorly. They control the evacuation of waste materials from the digestive and urinary systems.

Muscles of the pelvic floor

Which protein makes up the thick filaments?

Myosin

Which of the abdominal muscles is responsible for taking in a breath?

None of the other choices are correct.

Your favorite niece just gave you a kiss. What muscle did she use?

Orbicularis oris

Which of the abdominal muscles inserts on the xiphoid process of the sternum with the pubic bone as the origin?

Rectus abdominis

Which is not a protein found in thin filaments?

Sarcomyosin

This muscle has its origin on the manubrium and sternal end of the clavicle and its insertion on the mastoid process.

Sternocleidomastoid

Which structures are reservoirs that store acetylcholine?

Synaptic vesicles

Which are the reservoirs that store the calcium required for muscle contraction?

Terminal cisternae

Which INCORRECTLY describes what happens during skeletal muscle contraction?

The Z discs of a sarcomere move farther apart.

A motor unit consists of a: A single motor neuron b: Neuromuscular junctions c: Muscle fibers d: Several motor neurons e: A single muscle fiber

a, b, c

Which are considered specific characteristics of all muscle cells? a: Contractility b: Extensibility c: Excitability d: Elasticity e: Originality

a, b, c, d

In general, a skeletal muscle is composed of a: Connective tissue sheaths b: Nerves c: Arteries d: Veins e: Muscle fibers

a, b, c, d, e

Which is the correct order of the connective tissue layers of a skeletal muscle, beginning with the outermost first? a: Endomysium b: Epimysium c: Perimysium

b, c, a

A muscle whose name has "profundus" in it is located

deep.

The major muscle involved in breathing is the

diaphragm

When a muscle is isometrically contracted, its length _______ change.

does not

A muscle whose name has "triceps" in it

has three muscle heads or tendons of origin.

The most laterally placed of the three erector spinae components, the ___________ group, is composed of three parts: cervical, thoracic, and lumbar.

iliocostalis

When a person blinks she is using her

orbicularis oculi.

The biceps brachii is an example of a ________ muscle.

parallel

The muscle that causes the look of fear by tensing the skin of the neck is the

platysma.

The narrow space that separates the motor neuron and the skeletal muscle fiber in a neuromuscular junction is called the

synaptic cleft.

The structure responsible for attaching muscle to bone is a

tendon.