Chapter 4: The Musculoskeletal System

Question 1

A chemical neurotransmitter that serves as a mediator in both the sympathetic and parasympathetic nervous system

Answer 1

Acetylcholine

Question 2

The enzyme that causes muscle relaxation by helping to break down acetylcholine

Answer 2

Acetylcholinesterase

Question 3

The strong tendon that joins the muscles in the posterior leg to the calcaneus

Answer 3

Achilles Tendon

Question 4

The component that makes up most of the thin protein filaments of the myofibrils

Answer 4

Actin

Question 5

Changes in electrical potential that occur when a cell or tissue has been activated by a stimulus

Answer 5

Action Potentials

Question 6

The short muscle that adducts the thigh

Answer 6

Adductor Brevis

Question 7

The long muscle that adducts the hip

Answer 7

Adductor Longus

Question 8

A prime mover; a muscle that contracts to provide most of a desired movement

Answer 8

Agonist

Question 9

The area within the pelvis that contains the anus

Answer 9

Anal Triangle

Question 10

Muscles working in opposition to each other

Answer 10

Antagonists

Question 11

Broad sheets of fibers that may attach to bones or to the coverings of other muscles

Answer 11

Aponeuroses

Question 12

A condition caused by damage, either through trauma or infection, to the facial nerve, resulting in an inability to move the facial muscles on the affected side

Answer 12

Bell Palsy

Question 13

Located in the posterior compartment of the leg; flexes and laterally rotates the knee and extends the hip

Answer 13

Biceps Femoris

Question 14

An intracellular protein to which calcium binds, resulting in muscle contraction

Answer 14

Calmodulin

Question 15

Muscle that is found only in the heart, providing the contractions needed to propel the blood through the circulatory system

Answer 15

Cardiac Muscle

Question 16

Accumulation of blood or fluid in a fascial compartment, typically following trauma, resulting in compression of blood vessels and tissue damage secondary to ischemia and, if not recognized and promptly treated, death of muscle and loss of the limb

Answer 16

Compartment Syndrome

Question 17

Anatomic spaces within the body that are enclosed by fascia

Answer 17

Compartments

Question 18

An organic compound in muscle tissue that can store and provide energy for muscle contraction

Answer 18

Creatine Phosphate

Question 19

The rapid movement of electrolytes across a cell membrane that changes the cell’s overall charge. This rapid shifting of electrolytes and cellular charges is the main catalyst for muscle contractions and neural transmissions

Answer 19

Depolarization

Question 20

A muscular dome that forms the undersurface of the thorax, separating the chest from the abdominal cavity. Contraction of this muscle (and the chest wall muscles) brings air into the lungs. Relaxation allows air to be expelled form the lungs

Answer 20

Diaphragm

Question 21

The delicate connective tissue surrounding individual muscular fibers

Answer 21

Endomysium

Question 22

A layer of connective tissue that closely surrounds skeletal muscles

Answer 22

Epimysium

Question 23

Groups of muscles that cause extension

Answer 23

Extensor Muscles

Question 24

Fluid outside of the cells, in which most of the body’s supply of sodium is contained; accounts for 15% of body weight

Answer 24

Extracellular Fluid

Question 25

Movement of the eyes in various directions

Answer 25

Extraocular Movements

Question 26

A layer of fiberous connective tissue outside the epimysium that seperates individual muscles and individual muscle groups

Answer 26

Facia

Question 27

Groups of muscles that cause flexion when contracted

Answer 27

Flexor Muscles

Question 28

Conduction areas between cells (eg, in visceral smooth muscle) that interconnect individual muscle cells

Answer 28

Gap Junctions

Question 29

An iron-containing protein within red blood cells that has the ability to bind to oxygen

Answer 29

Hemoglobin

Question 30

A movable part of the body to which a skeletal muscle is fastened at a movable joint

Answer 30

Insertion

Question 31

Branching fibers in cardiac muscle that allow action potentials to pass from cell to cell

Answer 31

Intercalated Disks

Question 32

The ability of a muscle to generate its own electrical activity

Answer 32

Intrinsic Automaticity

Question 33

A metabolic end product of the breakdown of glucose that accumulates when metabolism proceeds in the absence of oxygen

Answer 33

Lactic Acid

Question 34

The flattened end of a motor neuron that transmits neural impulses to a muscle

Answer 34

Motor End Plate

Question 35

Specialized nerve cells that deliver an impulse to muscle cells, causing them to contract

Answer 35

Motor Neurons

Question 36

A motor neuron and the muscle fibers that it controls

Answer 36

Motor Unit

Question 37

One of the two types of smooth muscle, it is formed into sheets of muscle (as in the walls of blood vessels), small bundles of muscles (as in the iris of the eye), or single cells (as in the capsule of the spleen)

Answer 37

Multiunit Smooth Muscle

Question 38

Fibers that contract causing movement; three types of muscle are present in the body: skeletal muscle, smooth muscle, and cardiac muscle

Answer 38

Muscle

Question 39

A bundle of skeletal muscle cells bound together by connective tissue and forming one of the constituent elements of a muscle

Answer 39

Muscle Fasciculus

Question 40

One that passes in many directions over a muscle fiber membrane after stimulation by acetylcholine

Answer 40

Muscle Impulse

Question 41

The bones and voluntary muscles of the body

Answer 41

Musculoskeletal System

Question 42

Threadlike structures that extend from one end of the muscle fiber to the other

Answer 42

Myofibrils

Question 43

An iron-containing red pigment, similar to hemoglobin, that is found in muscle fibres

Answer 43

Myoglobin

Question 44

The component that makes up most of the thick protein filaments of the myofibrils

Answer 44

Myosin

Question 45

Electrochemical changes transmitted by neurons to other neurons and to cells outside the nervous system

Answer 45

Nerve Impulse

Question 46

The junction between a motor neuron and a muscle fiber; one type of a synapse

Answer 46

Neuromuscular Junction

Question 47

Chemical substances that transmit nerve impulses across a synapse

Answer 47

Neurotransmitters

Question 48

A relatively immovable part of the body where a skeletal muscle is fastened at a movable joint

Answer 48

Origin

Question 49

The amount of oxygen that liver cells need to convert lactic acid into glucose, as well as the amount needed by muscle cells to restore adenosine triphosphate and creatine phosphate levels

Answer 49

Oxygen Debt

Question 50

Deep muscles of the medial compartment that adduct, flex, and internally rotate the theigh

Answer 50

Pectineus Muscles

Question 51

The largest muscle of the chest wall; it adducts and internally rotates the shoulder

Answer 51

Pectoralis Major

Question 52

The connective tissue sheath that surrounds a muscle and forms sheaths for the bundles of muscle fibers

Answer 52

Perimysium

Question 53

The area below the coccygeus and levator ani muscles, which forms the floor of the pelvis

Answer 53

Perineum

Question 54

When a cell is at rest, ions are actively transported into and out of the cell to create an electrochemical gradient across the cell membrane

Answer 54

Polarized

Question 55

The muscle in a group of muscles that has the major role in movement

Answer 55

Prime Mover

Question 56

Muscle contained in the anterior compartment of the thigh that extends the knee when contracted

Answer 56

Quadriceps Femoris

Question 57

The linear muscle of the midline of the abdomen

Answer 57

Rectus Abdominis

Question 58

The process by which ions are moved across the cell wall to return to a polarized state

Answer 58

Repolarization

Question 59

A special group of four muscles that forms a cap over the proximal humerus and ties the humerus to the scapula; it controls rotation at the shoulder joint

Answer 59

Rotator Cuff

Question 60

The thin transparent sheath surrounding a striated muscle fiber

Answer 60

Sarcolemma

Question 61

The repeating patterns of striation units that appear along each skeletal muscle fiber

Answer 61

Sarcomeres

Question 62

A system of membranes that transport materials in muscle cells

Answer 62

Sarcoplasmic Reticulum

Question 63

The longest muscle in the human body, it is located in the anterior compartment of the thigh and flexes both the hip and knee when it contracts

Answer 63

Sartorius Muscle

Question 64

Muscles of respiration that elevate the first two ribs during inspiration

Answer 64

Scalene Muscles

Question 65

Striated muscles that are under direct volitional control of the brain; also called voluntary muscle

Answer 65

Skeletal Muscle

Question 66

A method of action of muscle contraction involving how sarcomeres shorten, with thick and thin filaments sliding past each other toward the center of the sarcomere from both ends

Answer 66

Sliding Filament Model

Question 67

Nonstriated muscle that carries out much of the automatic work of the body, such as moving food through the digestive tract and dilating and constricting the pupils of the eye; also called involuntary muscle

Answer 67

Smooth Muscle

Question 68

Areas of alternating, colored bands of skeletal muscle fiber

Answer 68

Striations

Question 69

A functional connection where neurons communicate with other cells

Answer 69

Synapse

Question 70

The space between neurons

Answer 70

Synaptic Cleft

Question 71

Muscles that work together to accomplish a particular movement

Answer 71

Synergists

Question 72

Tough, ropelike cords of fibrous tissue that attach muscles to bones

Answer 72

Tendons

Question 73

A test used to elevate the integrity of the Achilles tendon for possible rupture

Answer 73

Thompson Test

Question 74

T-tubules; membranous channels extending inward and passing through muscle fibers

Answer 74

Transverse Tubules

Question 75

An actin-binding protein that regulates muscle contraction and other actin-related mechanical function of the body

Answer 75

Tropomyosin

Question 76

A regulatory protein in the actin filaments of skeletal and cardiac muscle that attaches to tropomyosin

Answer 76

Troponin

Question 77

The region within the pelvis that contains the structures of the urogenital system

Answer 77

Urogenital Triangle

Question 78

Sheets of muscle found in the digestive, reproductive, and urinary tracts

Answer 78

Visceral Smooth Muscle

Question 79

A layman's term for traumatic soft-tissue injury to the structures of the neck, associated with sudden flexion or extension

Answer 79

Whiplash

Question 80

Supination of the forearm against resistance to evaluate whether a patient has bicipital tendinitis

Answer 80

Yergason Test