Chapter 1: Muscular, Neuromuscular, and Respiratory Systems

Question 1

epimysium

Answer 1

connective tissue layer that covers the external surface of the muscle and holds fascicles together

Question 2

bone periosteum

Answer 2

specialized connective tissue covering all bones

Question 3

proximal

Answer 3

closer to the trunk

Question 4

distal

Answer 4

farther from the trunk

Question 5

superior

Answer 5

closer to the head

Question 6

inferior

Answer 6

closer to the feet

Question 7

origin

Answer 7

described as proximal attachment

Question 8

insertion

Answer 8

described as distal attachment

Question 9

muscle fibers

Answer 9

called muscle cells; long cylindrical cells 50-100 um in diameter

Question 10

fascicle

Answer 10

bundle of muscle fibers

Question 11

perimysium

Answer 11

connective tissue layer that surrounds the fascicle and holds them together

Question 12

endomysium

Answer 12

thin layer of connective tissue that surrounds and loosely binds nearby muscle fibers

Question 13

sarcolemma

Answer 13

plasma membrane in muscle fibers

Question 14

motor neuron

Answer 14

nerve cell

Question 15

neuromuscular junction

Answer 15

called motor end plate; junction between motor neuron and the muscle fibers it innervates

Question 16

motor unit

Answer 16

a motor neuron and the muscle fibers it innervates

Question 17

sarcoplasm

Answer 17

the cytoplasm of a muscle fiber

Question 18

myofibril

Answer 18

contractile proteins in a muscle fiber that are organized into elongated bundles

Question 19

myofilament

Answer 19

contractile proteins found in myofibrils; actin and myosin

Question 20

cross-bridges

Answer 20

globular heads that protrude away from the myosin filament at regular intervals

Question 21

sarcomere

Answer 21

portion of myofibril located between two z discs; where actin and myosin are organized longitudinally

Question 22

A-band

Answer 22

corresponds with the alignment of the myosin filaments; dark bands

Question 23

I-band

Answer 23

corresponds with the areas in two adjacent sarcomeres that contain only actin filaments; light bands

Question 24

Z-line

Answer 24

in the middle of the I-band and appears as a thick, dark line running longitudinally through the I-band

Question 25

H-zone

Answer 25

area in the center of the sarcomere where only myosin filaments are present

Question 26

sarcoplasmic reticulum

Answer 26

loose network of flattened tubules that surrounds the myofibrils in muscle fibers

Question 27

T-tubules

Answer 27

tube-like extensions of sarcolemma that run over and around the sarcoplasmic reticulum

Question 28

triad

Answer 28

T-tubule and two terminal cisternae

Question 29

terminal cisternae

Answer 29

expanded regions of the sarcoplasmic reticulum that are found on both sides of the T-tubules

Question 30

action potential

Answer 30

electrical nerve impulse

Question 31

sliding filament theory

Answer 31

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

Question 32

troponin

Answer 32

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

Question 33

tropomyosin

Answer 33

runs along the length of the actin filament in the groove of the double helix; slides when calcium binds to troponin

Question 34

slow twitch

Answer 34

Type Ia and Ic

Question 35

fast twitch

Answer 35

Type IIa and IIc and IIx

Question 36

recruitment

Answer 36

process involving an increase in force through varying the number of motor units that are activated

Question 37

proprioceptors

Answer 37

specialized sensory receptors located within joints, muscles, and tendons; relay information to the central nervous system

Question 38

muscle spindles

Answer 38

proprioceptors that consist of several modified muscle fibers enclosed in a sheath of connective tissue

Question 39

golgi tendon organs

Answer 39

proprioceptors located in tendons near the myotendinous junctions and are attached end to end with extrafusal muscle fibers

Question 40

heart

Answer 40

muscular organ comprised of two interconnected but separate pumps; right side pumps blood through lungs; left side pumps blood through rest of body

Question 41

atrium

Answer 41

deliver blood to the ventricles

Question 42

ventricle

Answer 42

supply the main force for moving blood through the pulmonary and peripheral circulations

Question 43

atrioventricular (AV) valves

Answer 43

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

Question 44

semilunar valves

Answer 44

aortic and pulmonary; prevents back flow from aorta and pulmonary arteries into the ventricles during ventricular relaxation

Question 45

sinoatrial (SA) node

Answer 45

intrinsic pacemaker; where rhythmic electrical impulses are normally initiated

Question 46

atrioventricular (AV) bundle

Answer 46

conducts the impulse to the ventricles

Question 47

left and right bundle branches

Answer 47

further divide into the Purkinje fibers and conduct impulses to all parts of the ventricles

Question 48

bradycardia

Answer 48

abnormally slow heart rate

Question 49

tachycardia

Answer 49

abnormally fast heart rate

Question 50

hemoglobin

Answer 50

iron-protein molecule carried by the red blood cells

Question 51

red blood cells

Answer 51

major component of blood; contain large quantity of carbonic anhydrase

Question 52

trachea

Answer 52

first generation respiratory passage

Question 53

bronchi

Answer 53

second generation passages

Question 54

alveoli

Answer 54

24th generation; where gases are exchanged in respiration