Chapter 1: Structure and Function of Body Systems

Question 1

dark band that is the length of the myosin filaments, NEVER CHANGES LENGTH

Answer 1

A band

Question 2

primary neurotransmitter that acts at the neuromuscular junction, excites the muscle fibers in the motor unit

Answer 2

acetylcholine

Question 3

thin protein myofilament

Answer 3

actin

Question 4

electrical nerve impulse

Answer 4

action potential

Question 5

all muscle fibers in the motor unit contract and develop force at the same time

Answer 5

all or none principle

Question 6

pressure inside the alveoli when the glottis is open and no air is flowing into or out of the lungs

Answer 6

alveolar pressure

Question 7

where gases are exchanged in respiration

Answer 7

alveoli

Question 8

valve that prevents backflow of blood from the aortic artery into the ventricle during ventricular relaxation

Answer 8

aortic valve

Question 9

small branches of arteries that act as control vessels through which blood enters the capillaries

Answer 9

arteriole

Question 10

sends signals to the ventricles

Answer 10

AV bundle

Question 11

where the impulse is delayed slightly before passing into the ventricles

Answer 11

AV node

Question 12

valves that prevent the flow of blood from the ventricles back into the atria during ventricular contraction

Answer 12

AV valves

Question 13

joints that allow movement around 2 perpendicular axis

Answer 13

biaxial joints

Question 14

specialized connective tissue covering all bones, where tendon attaches

Answer 14

bone periosteum

Question 15

fewer than 60 bpm

Answer 15

bradycardia

Question 16

second generation respiratory passage

Answer 16

bronchi

Question 17

third generation respiratory passage

Answer 17

bronchiole

Question 18

facilitate the exchange of oxygen, fluid, nutrients, electrolytes, hormones, and other substances between the blood and interstitial fluid in various tissues of the body, have thin permeable walls

Answer 18

capillary

Question 19

joints that allow little movement

Answer 19

cartilaginous joints

Question 20

formed by myosin heads attaching to actin filaments

Answer 20

crossbridge

Question 21

“contraction,” reversal of the membrane electrical potential

Answer 21

depolarization

Question 22

ventricular relaxation

Answer 22

diastole

Question 23

process that allows oxygen and carbon dioxide to move through the alveolar capillary membrane

Answer 23

diffusion

Question 24

graphic representation of the electrical activity of the heart

Answer 24

electrocardiogram (ECG)

Question 25

fibrous connective tissue that surrounds each individual muscle fiber

Answer 25

endomysium

Question 26

fibrous connective tissue that surrounds the entire muscle belly

Answer 26

epimysium

Question 27

a bundle of muscle fibers grouped by fiber type

Answer 27

fascicle

Question 28

motor unit that develops force and relaxes rapidly, has a short twitch time

Answer 28

fast twitch fibers

Question 29

joints that allow virtually no movement

Answer 29

fibrous joints

Question 30

proprioceptors located in series near the myotendinous junction, SENSE MUSCLE CONTRACTION + CAUSE MUSCLE INHIBITION

Answer 30

golgi tendon organ (GTO)

Question 31

iron protein molecule carried by the red blood cells that transports oxygen, also an acid-base buffer

Answer 31

hemoglobin

Question 32

type of smooth cartilage that covers the articulating ends of bones

Answer 32

hyaline cartilage

Question 33

area in the center of the sarcomere where only myosin is present, shortens with contraction

Answer 33

H zone

Question 34

corresponds with the areas in two adjacent sarcomeres that contain only actin filaments, shorten with muscle contraction

Answer 34

I band

Question 35

two types of modified muscle fibers within the muscle spindle

Answer 35

intrafusal and extrafusal fibers

Question 36

valve that prevents the back flow of blood from the left ventricle back into the left atrium during ventricular contraction

Answer 36

mitral valve

Question 37

nerve cell

Answer 37

motor neuron

Question 38

motor neuron + muscle fibers it innervates

Answer 38

motor unit

Question 39

joints that allow movement around 3 axis

Answer 39

multiaxial joints

Question 40

muscle cells made of myofibrils

Answer 40

muscle fiber

Question 41

prorpioceptors that consist of several modified muscle fibers enclosed in a sheath of connective tissue, SENSE MUSCLE STRETCH + CAUSE MUSCLE CONTRACTION

Answer 41

muscle spindle

Question 42

heart muscle

Answer 42

myocardium

Question 43

contain what contracts the muscle (myofilaments)

Answer 43

myofibril

Question 44

protein filaments of myofibrils in muscle cells

Answer 44

myofilament

Question 45

thick protein myofilament

Answer 45

myosin

Question 46

junction between a motor neuron and the muscle fiber it innervates

Answer 46

neuromuscular junction

Question 47

fibrous connective tissue that surrounds one bundle of muscle fibers (fascicle)

Answer 47

perimysium

Question 48

membranes enveloping the lungs and lining the chest walls

Answer 48

pleura

Question 49

pressure in the narrow space between the lung pleura and the chest wall pleura, normally slightly negative

Answer 49

pleural pressure

Question 50

pulling action of myosin on actin

Answer 50

power stroke

Question 51

specialized sensory receptors located within joints, muscles, and tendons that send kinesthetic information to the brain

Answer 51

proprioceptors

Question 52

valve that prevents back flow of blood from the pulmonary artery into the ventricle during ventricular relaxation

Answer 52

pulmonary valve

Question 53

further divides and conducts impulses to all parts of the ventricles

Answer 53

purkinje fibers

Question 54

atrial depolarization

Answer 54

P wave

Question 55

ventricular depolarization + atrial repolarization

Answer 55

QRS complex

Question 56

major cell components of blood that facilitate carbon dioxide removal

Answer 56

red blood cell

Question 57

"filling" or "relaxation," occurs shortly after depolarization to allow the ventricles to recover

Answer 57

repolarization

Question 58

muscle fiber membrane

Answer 58

sarcolemma

Question 59

smallest contractile unit of skeletal muscle, contain actin and myosin

Answer 59

sarcomere

Question 60

cytoplasm of muscle fiber

Answer 60

sarcoplasm

Question 61

system of tubules surrounding each myofibril, stores calcium

Answer 61

sarcoplasmic reticulum

Question 62

valves that prevent backflow of blood from the aorta and pulmonary arteries into the ventricles during ventricular relaxation

Answer 62

semilunar valves

Question 63

pacemaker of the heart, where the rhythmic electrical impulses are normally initiated

Answer 63

SA node

Question 64

theory that states that the actin filaments at each end of the sarcomere slide inward on myosin filaments, pulling the Z lines toward the center of the sarcomere and thus shortening the muscle fiber

Answer 64

sliding filament theory

Question 65

motor unit that develops force and relaxes slowly, has a long twitch time

Answer 65

slow twitch fiber

Question 66

joints that allow the most movement

Answer 66

synovial joints

Question 67

ventricular contraction

Answer 67

systole

Question 68

more than 100 bpm

Answer 68

tachycardia

Question 69

maximal amount of force that motor unit can develop, twitches begin to merge and eventually completely fuse together

Answer 69

tetanus

Question 70

first generation respiratory passage

Answer 70

trachea

Question 71

valve that prevents the back flow of blood from the right ventricle back into the right atrium during ventricular contraction

Answer 71

tricuspid valve

Question 72

protein molecule that is roped around the actin filament, covers and uncovers actin binding site

Answer 72

tropomyosin

Question 73

protein molecule that is situated at regular intervals along the actin filament and has a high affinity for calcium ions

Answer 73

troponin

Question 74

tubes that run perpendicular to the sarcoplasmic reticulum

Answer 74

T tubule

Question 75

ventricular repolarization

Answer 75

T wave

Question 76

short period of activation of the muscle fibers within the motor unit

Answer 76

twitch

Question 77

slow twitch oxidative fiber type, efficient and fatigue resistant, and have a high capacity for aerobic energy supply but a limited potential for rapid force development (endurance athletes)

Answer 77

type I muscle fiber

Question 78

fast twitch (mixed) fiber type, inefficient and fatiguable, have a low aerobic power and high anaerobic power, and rapid force development (power athletes)

Answer 78

type IIa muscle fiber

Question 79

fast twitch glycolytic fiber type, show less resistance to fatigue (1-5 RM)

Answer 79

type IIx muscle fiber

Question 80

hinge joints that rotate around one axis

Answer 80

uniaxial joints

Question 81

collect blood from capillaries

Answer 81

venule

Question 82

the walls of the sarcomere, dark line in the middle of the I band

Answer 82

Z line

Question 83

dictated by the number of crossbridges that are formed between actin and myosin at any instant in time

Answer 83

muscle force production

Question 84

the discharge of an action potential from a motor nerve signals the release of calcium from the sarcoplasmic reticulum into the myofibril, causing what to develop in the muscle

Answer 84

tension

Question 85

what two things are necessary for cross bridge cycling with actin and myosin filaments?

Answer 85

calcium and ATP

Question 86

motor units are composed of muscle fibers with specific morphological and physiological characteristics that determine their what?

Answer 86

functional capacity

Question 87

varies through change in the frequency of activation of individual motor units or change in the number of activated motor units

Answer 87

force output of a muscle

Question 88

primary function of the respiratory system

Answer 88

basic exchange of oxygen and carbon dioxide

Question 89

information concerning kinesthetic sense, or conscious appreciation of the position of body parts with respect to gravity (processed at subconscious levels)

Answer 89

proprioception

Question 90

the assistance that contracting muscles provide to the circulatory system (veins) to help blood return to the heart, rather than pooling in the lower extremities

Answer 90

skeletal muscle pump