Muscles

Question 1

characteristics of muscles

Answer 1

excitability, contractility, extensibility, elasticity

Question 2

excitability

Answer 2

ability of muscle tissue to receive and respond to stimuli

Question 3

contractility

Answer 3

ability to shorten and thicken, contract, when a sufficient stimulus is received

Question 4

extensibility

Answer 4

he ability of muscle tissue to be stretched

Question 5

elasticity

Answer 5

ability of muscle to return to its original shape after contraction

Question 6

3 functions of muscles

Answer 6

motion, posture and heat production

Question 7

skeletal

Answer 7

striated, long cylindrical, multinucleated, voluntary and found anywhere attached to bone

Question 8

fascia

Answer 8

sheet/ broad band of fibrous connective tissue beneath the skin/around muscles and other organs

Question 9

superficial fascia

Answer 9

immediately deep to the skin, adipose tissue and loose connective

Question 10

deep fascia

Answer 10

dense connective tissue that lines the body wall and extremities and holds muscles together separating them into functioning groups

Question 11

epimysium

Answer 11

fascia around the entire muscle

Question 12

fascicles

Answer 12

muscle bundles

Question 13

perimysium

Answer 13

fascia around fascicles

Question 14

endomysium

Answer 14

fascia around each muscle fiber

Question 15

tendons

Answer 15

fibrous connective tissue that connects muscle fascia to perostium of the bone

Question 16

tendon sheaths

Answer 16

tubes of fibrous connective tissue that encloses certain tendons

Question 17

origin

Answer 17

less moveable end

Question 18

insertion

Answer 18

more moveable end

Question 19

what kind of nerve and blood supply penetrates a skeletal muscle

Answer 19

one artery and one or two veins, long winding capillaries go within endomysium, each skeletal muscle fiber usually makes contact with a portion of nerve cell called synaptic end bulb

Question 20

sarcolemma

Answer 20

cell membrane of muscle fiber

Question 21

sarcoplasm

Answer 21

cytoplasm of muscle cell

Question 22

what is the sarcoplasmic reticulum

Answer 22

specialized smooth ER that regulates calcium concentration

Question 23

where is the sarcoplasmic reticulum found

Answer 23

in muscle fibers

Question 24

what are the terminal cisternae

Answer 24

internal sacs

Question 25

what are T tubules

Answer 25

transverse tubules that are extensions of sarcolemma that conduct impulses from sarcolemma down into the cell

Question 26

what are myofibrils

Answer 26

tiny structures found in muscle fibers

Question 27

what are the 2 types of myofilaments

Answer 27

actin and myosin

Question 28

thin filaments

Answer 28

actin

Question 29

thick filaments

Answer 29

myosin

Question 30

When the sarcomere shortens, what happens, if anything, to the I band, to the H zone, and to the A band

Answer 30

While the I band and H zone will disappear or shorten, the A band length will remain unchanged.

Question 31

what is a muscle fiber

Answer 31

composed of fibrils, surrounded by sarcolemma

Question 32

What are the myosin filaments composed of

Answer 32

head/cross bridges, ATP and actin binding sites

Question 33

what are the actin filaments composed of

Answer 33

actin (f & g) tropomyosin, and troponin

Question 34

where are the actin and ATP binding sites found

Answer 34

myosin

Question 35

where are the myosin-binding sites found

Answer 35

actin

Question 36

what might be covering the myosin binding sites

Answer 36

tropomyosin

Question 37

troponin has a high affinity for 3 different substances

Answer 37

actin, tropomyosin and calcium ions

Question 38

when a calcium ions bind with troponin what happens to the troponin tropomysin complex? What then happens?

Answer 38

moves to expose active sites on actin and no more tropomysin covering myosin

Question 39

Where is the ATP binding and what happens

Answer 39

ATP binding is at the head of myosin releasing actin and myosin, then myosin head returns to original position

Question 40

motor neuron

Answer 40

neuron that stimulates muscle tissue

Question 41

what is a neuromuscular junction

Answer 41

axon terminal of a motor neuron along with the portion of the sarcolemma that is close to the axon terminal

Question 42

what is a synapse

Answer 42

junction where signal is passed

Question 43

name the neurotransmitter used at neuromuscular junctions

Answer 43

acetylcholine

Question 44

substance that binds with acetylcholine and breaks down acetic acid and choline

Answer 44

acetylcholinesterase

Question 45

motor unit

Answer 45

motor neuron and all muscle fibers that it stimulates

Question 46

are all motor neurons the same size

Answer 46

no relationship between muscle cell size

Question 47

eccentric contraction

Answer 47

Eccentric contraction occurs when the total length of the muscle increases as tension is produced

Question 48

concentric contraction

Answer 48

the muscle tension rises to meet the resistance then remains stable as the muscle shortens.

Question 49

isometric contraction

Answer 49

a muscle contraction without motion

Question 50

isotonic contraction

Answer 50

tension remains the same, whilst the muscle's length changes.

Question 51

synapse

Answer 51

the points of contact between neurons where information is passed from one neuron to the next