ANAT260 - A & P

Which of the following muscles is used to smile?

- zygomaticus major - levator labii superioris - levator anguli oris

Sequence of Events (Sarcomere Contraction)

1. Ca2+ released from the SR. 2. Ca2+ triggers exposure of active sites. 3. Myosin head link to the active sites. 4. Myosin heads pivot, producing tension. 5. ATP binds myosin; cross-bridges broken. 6. Myosin heads reset.

Without lateral rotation of the humerus by the teres minor and infraspinatus muscles, the maximum angle of abduction by the deltoid would be __________.

90 degrees

Adam is an athletic teen who has seen his neighbor, Regina, an 85-year-old woman, struggling with her grocery bags. Adam goes over and holds her bags of canned goods while she finds her house key. It takes her a few minutes, and Adam holds the bags in his arms while she searches. Which of the following could be said of Adam's arm muscles?

Adam alternates activity between multiple motor units of his arm muscles in order to hold the bags and not drop them

Which of the statements is true of a synergistic muscle?

It supports an agonistic muscle and may stabilize a motion.

John is sitting with Marcy on his left and Abby on his right, and he contracts his left lateral rectus and his right medial rectus eye muscles. Which person is he looking at?

Marcy

Which of the following changes occurs in the sarcomere during muscle contraction?

The zone of overlap increases in size.

The anterior axial muscle that crosses the glenohumeral joint is the pectoralis major muscle.

True.

The teres major adducts the arm but does not __________ the arm.

abduct

The primary function of the pectoral girdle is to __________.

act as an attachment site for muscles that move the arm

Muscles contract and produce movement at joints. The direction of the force applied by a muscle at a joint is known as its __________.

action line

One of the actions of the latissimus dorsi muscle is to

adduct the arm

Which of the following muscles does NOT cross two joints?

adductor magnus

If a muscle flexes and medially rotates the arm, its action line would cross the ______________ aspect of the shoulder joint.

anterior

The origin of the rectus femoris is the ____________.

anterior inferior iliac spine

The deltoid muscle fibers are separated into __________.

anterior, middle, and posterior

The muscle found deep to the masseter is the _____.

buccinator

Which of the following is NOT a muscle that forms the pelvic diaphragm?

bulospongiosus

Atoms of which of the following elements are needed in order for a muscle contraction to occur (for the thin filaments to interact with the thick filaments of a muscle cell)?

calcium

Which of the following areas of the brain adjusts the output of other somatic motor centers in the central nervous system?

cerebellum

The area of the brain where memory is processed and stored is the __________.

cerebrum

The pectoral girdle consists of the __________.

clavicle and scapula

The orbicularis oculi _____.

closes the eye

What is the general function of the external and internal oblique muscles as well as the transversus abdominis?

compression of the abdomen

The actions of the internal obliques include __________.

compression of the abdomen to assist in forced expiration

The scalp or epicranium _____.

contains the occipitofrontalis muscle that has two muscle bellies

The __________ is a prime mover of the glenohumeral joint during flexion.

deltoid

The muscle that depresses and draws the corner of the mouth laterally is the _____.

depressor anguli oris

The origin of the serratus anterior includes __________ ribs.

eight

Muscles of the urogenital diaphragm include the _____.

external urethral sphincter

Where in the body might you find the muscles that contain the highest amount of fast-twitching fibers?

eye

The origin of the external obliques includes ribs __________.

five through twelve

Both heads of the biceps femoris muscle __________.

flex the leg at the knee

The soleus muscle __________ the foot at the ankle and is innervated by the __________.

flexes; tibial nerve

The actions of the internal intercostals are most important during __________.

forced expiration

Abduction requires the action of two muscles, and adduction requires the action of __________.

four muscles

If Alyssa sees something that surprises her and she raises her eyebrows, which muscle has she contracted?

frontal belly of occipitofrontalis

The soleus muscle shares an insertion with the __________.

gastrocnemius muscle

The infraspinatus inserts on the ____________ of the humerus.

greater tubercle of the humerus

Which of the following areas of the brain provides a link between the nervous system and the endocrine system?

hypothalamus

The external intercostals elevate the rib cage during __________.

inspiration

All fibers of the pectoralis major muscle converge on the lateral edge of the__________.

intertubercular sulcus

Cerebrospinal fluid can exit the fourth ventricle via all of the following EXCEPT the __________.

interventricular foramen

The tibialis anterior muscle dorsiflexes the foot at the ankle and also assists in __________ of the foot.

inversion

The muscle that lies next to the ramus and tuberosity of the ischium is the _____.

ischiocavernosus

The rectus femoris muscle extends the leg at the __________.

knee

The trapezius muscle may be separated into all of the following groups, except __________.

lateral

The origins of the lateral head of the gastrocnemius muscle are the __________.

lateral condyle and posterior surface of the femur

The actions of the rhomboid major on the scapula do not include __________.

lateral rotation

Cerebrospinal fluid is produced by the choroid plexuses. In which of the following regions can cerebrospinal fluid be made?

lateral ventricles, third ventricle, and fourth ventricle

The posterior axial muscle that crosses the glenohumeral joint is the __________.

latissimus dorsi

The four muscles that comprise the posterior group of the pectoral girdle are the __________.

levator scapulae, rhomboideus minor, rhomboideus major, and trapezius

The masseter is innervated by the _____________ branch of the trigeminal nerve.

mandibular

The masseter muscle originates on the __________.

medial surfaces of the maxilla and the zygomatic arch as well as the inferior border of the zygomatic arch

Where are the autonomic reflex centers located in the brain for heart rate and breathing?

medulla oblongata

The contraction of a single muscle cell is called a __________.

muscle twitch

The latissimus dorsi inserts __________.

on the intertubercular groove of the humerus

You've probably heard of incidents in which people have done "superhuman" feats in extreme crises, for example, a mother raising a small vehicle off her child after a car accident. During these events, muscles contract to their maximum ability. What is the term given to the force generated by muscles in those events?

peak tension

The origins of the rectus abdominus muscle are on the __________.

pubic bone

All fibers of the triceps brachii are innervated by the __________.

radial nerve

The two heads of the biceps brachii combine to insert on the __________.

radial tuberosity

If Rob says he wants to make his "six-pack" muscles more visible, which muscle(s) is he going to exercise?

rectus abdominis muscle

The infraspinatus muscle is included in the __________ muscles.

rotator cuff

Which of the following muscles flexes both the thigh and the leg?

sartorius

The anterior muscles of the thigh that originate on the os coxae are __________.

sartorius; rectus femoris

Which movement results after the contraction of the serratus anterior muscle?

scapular protraction and rotation

Which of the following is considered one of the hamstring muscles?

semimembranosus

A __________ muscle does not insert close to a joint. It acts both to produce movement and to stabilize the joint.

shunt

All fibers of the trapezius muscle are innervated by the __________.

spinal accessory nerve

The angle of which muscle prevents the humeral head from sliding upward out of the joint as the arm is raised?

subscapularis

Downward dislocation of the humerus from the glenohumeral joint when carrying weight is prevented by the __________.

supraspinatus muscle

The temporalis muscle originates on the __________ and inserts on the __________.

temporal fossa; coronoid process of mandible

The fusion of the epimysium, perimysium, and endomysium at the end of a muscle is called a __________.

tendon

Which of the following muscles assists during extension of the glenohumeral joint, but is not as a prime mover?

teres major

Which muscle is not part of the rotator cuff?

teres major muscle

General sensory information on its way to the cerebrum gets processed and relayed by which of the following areas of the brain?

thalamus

Which nerve innervates the muscles of mastication?

the trigeminal nerve

While working in his garden, Bill places several large rocks in the bed of his wheelbarrow. He pulls up on the handles of the wheelbarrow using it as a lever to lift the rocks. Where is the fulcrum of Bill's lever?

the wheel of the wheelbarrow

A pitcher throwing a baseball is using the most common type of lever in the body, a __________ lever. The speed of the ball and the distance traveled are magnified at the expense of force.

third-class

The gastrocnemius muscle is innervated by the __________.

tibial nerve

The temporalis muscle is innervated by the mandibular branch of the __________.

trigeminal nerve

Contraction is initiated by release of calcium ions from the terminal cisternae of the sarcoplasmic reticulum. To what molecule do the calcium ions bind?

troponin

The amount of tension produced by a muscle peaks when the _____________ is large, thus allowing the formation of many cross-bridges.

zone of overlap