chapter 9: muscles and tissues

Question 1

skeletal muscle tissue is found…

Answer 1

in organs that attach and cover the skeleton

Question 2

characteristics of skeletal muscles

Answer 2

• have striations
• voluntary muscle

Question 3

characteristics of cardiac muscles

Answer 3

• has striations
• involuntary muscle

Question 4

characteristics of smooth muscle

Answer 4

• found in walls of hollow visceral organs
• non-striated
• involuntary muscle

Question 5

what muscle is found in walls of hollow visceral organs

Answer 5

smooth muscle

Question 6

characteristics of muscle tissue (4)

Answer 6

• excitability
• contractibility
• extensibility
• elasticity

Question 7

muscle functions (4)

Answer 7

• produce movement
• maintain posture and position
• stabilize joints
• generate heat

Question 8

skeletal muscle is made of … (4)

Answer 8

• muscle fibers
• nerves
• blood vessels
• connective tissues

Question 9

what is epimysium

Answer 9

• outside the muscle
• dense irregular

Question 10

what is perimysium

Answer 10

• dense irregular
• covers fascicles
• made of collagen and elastin

Question 11

what is fascicle

Answer 11

grouped muscle fibers that resemble bundles of sticks

Question 12

what is endomysium

Answer 12

• within the muscle
• wispy sheath of fine areolar connective tissue
• divides each muscle fiber

Question 13

what is insertion

Answer 13

the moveable bone

Question 14

what is origin

Answer 14

the less or immovable bone

Question 15

2 types of muscle insertions

Answer 15

• direct/ fleshy
• indirect

Question 16

function of tendon/ aponeurosis

Answer 16

anchors muscle to the connective tissue covering of skeletal element or to fascia of other muscle

Question 17

what is the contractile unit of the muscle

Answer 17

sarcomere

Question 18

plasma membrane of the muscle fiber

Answer 18

sarcolemma

Question 19

cytoplasm of muscle cell

Answer 19

sarcoplasm

Question 20

granules of stored glycogen that provide glucose during muscle cell activity for ATP production

Answer 20

glycosomes

Question 21

red pigment that stores oxygen

Answer 21

myoglobin

Question 22

myofibrils are

Answer 22

make up a single muscle fiber, rod shaped

Question 23

myofibrils are made of…

Answer 23

sarcomeres

Question 24

sarcomeres contain…

Answer 24

myofilaments

Question 25

dark striation

Answer 25

A band

Question 26

light striation

Answer 26

I band

Question 27

lighter region of A band

Answer 27

H zone

Question 28

describe sarcomere

Answer 28

smallest contractile unit of muscle fiber

Question 29

2 types of myofilaments

Answer 29

• myosin
• actin

Question 30

thick filaments contain …

Answer 30

myosin (red)

Question 31

thin filaments contain …

Answer 31

actin (blue)

Question 32

function of tropomyosin

Answer 32

rod shaped protein that spirals about the actin core and help stiffen and stabilize

Question 33

function of troponin

Answer 33

globular protein, calcium-regulatory protein

Question 34

what is dystrophin

Answer 34

links thin filaments to integral proteins of sarcolemma

Question 35

events at neuromuscular junction (4)

Answer 35

• motor using fires action potential (AP) down axon
• Ach is release by neuron axon terminal into synaptic cleft
• ACh binds receptors on junctional folds of sarcolemma
• Ach binding causes depolarization called EEP

Question 36

what happens in muscle fiber excitation

Answer 36

EEP triggers an AP

Question 37

what happens in excitation-contraction coupling

Answer 37

• Ap in sarcolemma travels down T tubes
• SR releases Ca^2+
• Ca^2+ binds to troponin, myosin heads bind actin

Question 38

what happens in cross bridge cycle

Answer 38

contraction occurs via cross bridge cycling

Question 39

what is a myogram

Answer 39

recording of contractile activity consisting of one or more recorded lines called tracings

Question 40

3 distinct phases of myogram

Answer 40

• latent period
• period of contraction
• period of relaxation

Question 41

what is the latent period

Answer 41

first few milliseconds following stimulation when excitation-contraction coupling is occurring

Question 42

what happens during wave summation

Answer 42

contractions become stronger due to stimulation before complete relaxation occurs

Question 43

stimuli that produce no observable contractions are called

Answer 43

threshold stimulus

Question 44

what do you call the strongest stimulus that increases contractile force

Answer 44

maximal stimulus

Question 45

first observable contraction is called…

Answer 45

threshold stimulus

Question 46

tetanus

Answer 46

smooth contraction due to rapid stimulation

Question 47

isotonic vs isometric contraction

Answer 47

isotonic- muscle develops tension to lift the load, muscle shortens and remains constant
isometric- muscle reaches peak tension developing capability but does not shorten

Question 48

2 types of isotonic contractions

Answer 48

concentric- muscle shortens and does work
eccentric- muscle generates force as it lengthens

Question 49

differentiate aerobic and resistance exercise

Answer 49

aerobic- stamina, causes dramatic change in slow, oxidative fibers
resistance- strength

Question 50

define muscle twitch

Answer 50

response of a muscle to a single stimulation