NURS 120 Module 5: Chapter 8

Abduction

moving away from the midline of the body; opposite motion of adduction

acetylcholine (ACh)

chemical neurotransmitter

Actin

contractile protein found in the thin myofilaments of skeletal muscle

Adduction

moving toward the midline of the body (or region); opposite of abduction

adductor muscle

any of several muscles that adduct a joint, moving a body part in from the side (lateral) and thus toward the midline (median or midsagittal plane) of the body or of the body region; for example, the pectoralis major and latissimus dorsi muscles contract together to pull the arm toward the trunk, thus adducting the shoulder joint

aerobic training

continuous vigorous exercise requiring the body to increase its consumption of oxygen and develop the muscles' ability to sustain activity over a long period

all or none

describing a process that occurs at maximum or not at all once it begins

Antagonist

any agent that has the opposite effect of the agent to which it is compared; for example, a hormone antagonist opposes the effect of the compared hormone

biceps brachii

the primary flexor of the forearm

biomechanical engineering

discipline of engineering that applies principles of mechanical engineering to biological systems, as in biomedical engineering

Bursa (pl., bursae)

small, cushionlike sac found alongside joints, cushioning moving bones

cardiac muscle

the type of muscle tissue that makes up most of the heart wall

carpal tunnel syndrome

muscle weakness, pain, and tingling in the radial side (thumb side) of the wrist, hand, and fingers—sometimes radiating to the forearm and shoulder; caused by compression of the median nerve within the carpal tunnel (a passage along the ventral concavity of the wrist)

Circumduction

the process of moving the distal end of a body part in a circular path

concentric contraction

type of isotonic muscle contraction in which a muscle's length decreases

Deltoid

triangular; for example, the deltoid muscle

Diaphragm

membrane or partition that separates one thing from another; the flat muscular sheet that separates the thorax and abdomen and is a major muscle of respiration

disuse atrophy

when prolonged inactivity results in the muscles shrinking in size

Dorsiflexion

angular movement when the top of the foot is elevated (brought toward the front of the leg) with the toes pointing upward

eccentric contraction

type of isotonic muscle contraction in which a muscle's length increases under a load

endurance training

continuous vigorous exercise requiring the body to increase its consumption of oxygen and developing the muscles' ability to sustain activity over a prolonged period

Ergonomics

applied study of workers and their work environment

Eversion

foot movement that turns the ankle so that the sole faces out to the side

Extension

increasing the angle between two bones at a joint

external oblique

the outermost layer of the anterolateral abdominal wall

Fatigue

loss of muscle power; weakness

fibularis group

leg muscles that plantar flex and evert the foot; formerly called peroneous group

Flexion

act of bending; decreasing the angle between two bones at the joint

frontal muscle

one of the muscles of facial expression; it moves the eyebrows and furrows the skin of the forehead

Gastrocnemius

superficial muscle of the calf of the leg, connected (along with the soleus muscle) to the calcaneus bone of the foot by way of the Achilles (calcaneal) tendon; its action is to dorsiflex the foot, bending the toes upward

gluteus maximus

major extensor of the thigh and also supports the torso in an erect position

hamstring muscle

any of the powerful flexors of the hip; the hamstring group is made up of the semimembranosus, semitendinosus, and biceps femoris muscles

Hypertrophy

increased size of a part caused by an increase in the size of its cells

Hypothermia

subnormal core body temperature below 37°C

iliopsoas

a flexor of the thigh and an important stabilizing muscle for posture

insertion

a muscle's attachment to a bone that moves when it contracts (as distinguished from its origin)

intercalated disk

any of the disklike cell connections that exist between cardiac muscle fibers

intercostal muscle

the respiratory muscles located between the ribs

internal oblique

the middle layer of the anterolateral abdominal walls

inversion

foot movement that turns the ankle so that the sole faces inward, toward the midline of the body

isometric contraction

type of muscle contraction in which muscle does not shorten

isotonic contraction

contraction in which the length changes but the tension seems to be about the same; a mobilizing kind of contraction

latissimus dorsi

an extensor of the arm

massage therapy

pressing, rubbing, or other manipulation of muscle and other soft tissue to prevent or treat a variety of health conditions

Masseter

large muscle of the cheek, used to lift the lower jaw (mandible) and thus provide chewing movement

Mastication

chewing

motor neuron

transmits nerve impulses from the brain and spinal cord to muscles and glandular epithelial tissues

motor unit

a single motor neuron with the muscle cells it innervates

muscle fiber

any of the specialized contractile cells of muscle tissue

muscle strain

overstretching or tearing skeletal muscle fibers resulting from overexertion or trauma

muscle tone

the tension of muscle or tonic contraction; characteristic of muscle of a normal individual who is awake

Myofilament

any of the ultramicroscopic threadlike protein structures found in cylindrical groupings within each muscle fiber and involved in muscle contraction

Myoglobin

large protein molecule in the cytoplasm of muscle cells that attracts oxygen and holds it temporarily

Myosin

contractile protein found in the thick filaments of skeletal muscle

neuromuscular junction (NMJ)

the point of contact between the nerve endings and muscle fibers

Nurse

health-care professional trained to care for the sick and injured

Nutritionist

professional consultant specializing in diet and food

Origin

a muscle's attachment to a bone that does not move when it contracts, as distinguished from insertion

oxygen debt

continued increased oxygen consumption that occurs after exercise; also called excess post-exercise oxygen consumption (EPOC)

Paralysis

loss of the power of motion, especially voluntary motion

pectoralis major

loss of the power of motion, especially voluntary motion

physical education

health professional who helps patients improve body movements and manage pain

Physician

health-care professional, usually holding a doctorate in medicine or related discipline, licensed to provide and supervise medical care

plantar flexion

action of the bottom of the foot being directed downward; this motion allows a person to stand on his or her tiptoes

Posture

position of the body

prime mover

the muscle responsible for producing a particular movement

Pronation

to turn the palm downward

quadriceps femoris

extensor of the leg

rectus abdominis

muscle that runs down the middle of the abdomen; protects the abdominal viscera and flexes the spinal column

Rotation

movement around a longitudinal axis; for example, shaking your head "no"

Sarcomere

contractile unit of muscle; length of a cylindrical grouping of myofilaments between two Z bands

skeletal muscle

the bones, cartilage, and ligaments that provide the body with a rigid framework for support and protection

sliding filament model

concept in muscle physiology describing the contraction of a muscle fiber in terms of the sliding of microscopic protein filaments past each other within the sarcomere in a manner that shortens all the sarcomeres and thus the entire muscle

smooth muscle

muscle that is not under conscious control; also known as involuntary muscle or visceral muscle; forms the walls of blood vessels and hollow organs

Sternocleidomastoid

"strap" muscle located on the anterior aspect of the neck

strength training

contracting muscles against resistance to enhance muscle hypertrophy

Supination

to turn the palm of the hand upward; opposite of pronate

Synergist

muscle that assists a prime mover

synovial membrane

connective tissue membrane lining the spaces between bones and joints that secretes synovial fluid

Tendon

a band or cord of fibrous connective tissue that attaches a muscle to a bone or other structure

tendon sheath

tube-shaped structure lined with synovial membrane that encloses certain tendons

Tenosynovitis

inflammation of a tendon sheath

tetanic contraction

sustained contraction

Tetanus

sustained muscular contraction

threshold stimulus

minimal level of stimulation required to cause a muscle fiber to contract

tibialis anterior

dorsiflexor of the foot

tonic contraction

special type of skeletal muscle contraction used to maintain posture

transversus abdominis

the innermost layer of the anterolateral abdominal wall

Trapezius

triangular muscle in the back that elevates the shoulder and extends the head backwards

triceps brachii

extensor of the elbow

Twitch

a quick, jerky response to a single stimulus

Zygomaticus

muscle that elevates the corners of the mouth and lips; also known as the smiling muscle

threadlike and cylindrical skeletal muscle cells appear in bundles. They are characterized by many crosswise stripes and multiple nuclei. Each fine thread is a muscle cell—usually called a

muscle that attaches to the bone

muscle is called this because of its cross stripes or striations

muscle is called this because its contractions can be controlled voluntarily.

muscle that composes the bulk of the heart

Fibers in this type of muscle tissue are also cylindrical, branch frequently, and then recombine into a continuous mass of interconnected tissue. They also have unique dark bands called intercalated disks, where the plasma membranes of adjacent cardiac fibers come in contact with each other.

fibers are tapered at each end and have a single nucleus. Because they lack cross stripes or striations, they are sometimes called nonstriated muscle fibers They are called involuntary because we normally do not have control over their contractions. Because of its location in many visceral structures, it is sometimes also called visceral muscle.

an organ composed mainly of skeletal muscle fibers and connective tissue.