lecture 10 skeletal muscle tissue

Question 1

primary tissue in

heart, walls of hollow organs and skeletal

Answer 1

muscle

Question 2

my-filaments are responsible for shortening of muscle cells

-actin and myosin are two type of myofilaments

Answer 2

contractility

Question 3

nerve signals excite muscle cells, causing electrical impulses to travel along the sarcolemma

Answer 3

excitability

Question 4

• contraction of a skeletal muscle stretches the opposing muscle
• smooth muscle is stretched by substances within that hollow organ

Answer 4

extensibility

Question 5

recoils after being stretched

Answer 5

elasticity

Question 6

plasma membrane of muscle cells

Answer 6

sarcolemma

Question 7

cytoplasm of muscle cells

Answer 7

sarcoplasm

Question 8

attached to skeleton

-moves body by moving the bones

Answer 8

skeletal muscle

Question 9

squeezes fluids and other substances through hollow organs

Answer 9

smooth muscle

Question 10

function as valves

• open to allow passage of a substance
• contract to close the passageway

Answer 10

sphincters

Question 11

• enables the body to remain sitting or standing

- muscle tone helps stabilize many synovial joints

Answer 11

maintain posture and stabilize joints

Question 12

• muscle contractions produce heat

- helps maintain normal body temperature

Answer 12

heat generation

Question 13

• packaged into skeletal muscles
• makes up 40% of body weight
• cells are striated

Answer 13

skeletal muscle tissue

Question 14

• occurs only in the walls of the heart
• straited
• involuntary

Answer 14

cardiac muscle tissue

Question 15

• occupies the walls of hollow organs
• lack striations
• involuntary

Answer 15

smooth muscle tissue

Question 16

dense regular connective tissue surrounding entire muscle

Answer 16

epimysium

Question 17

surrounds each fascicle

Answer 17

perimysium

Question 18

group of muscle fibers

Answer 18

fascicle

Question 19

a fine sheath of connective tissue wrapping each muscle cell

Answer 19

endomysium

Question 20

-most skeletal muscles run from one bone to another

Answer 20

muscle attachments

Question 21

less movable attachment

Answer 21

origin

Question 22

more movable attachment

Answer 22

insertion

Question 23

CT fibers are short

Answer 23

fleshy attachments

Question 24

CT forms a tendon or aponeurosis

Answer 24

indirect attachements

Question 25

bone markings present where tendons meet bones

Answer 25

tubercles, trochanters, and crests

Question 26

- fibers are long cylindrical - huge cells - several centimeters - each cell formed by fusion of embryonic cells - multinucleate

Answer 26

skeletal muscle fiber

Question 27

- long rods within cytoplasm | - make up 80% of cytoplasm

Answer 27

myofibrils

Question 28

long row of repeating segments

Answer 28

sarcomeres

Question 29

boundaries of each sarcomere

Answer 29

z disc (line)

Question 30

extend from Z disc toward center of sercomere

Answer 30

thin actin filaments

Question 31

located in the center of the sarcomere - overlap inner ends of the thin filaments - contain ATP enzymes

Answer 31

thick (myosin) filaments

Question 32

- full length of the thick filament | - includes inner end of thin filaments

Answer 32

A bands

Question 33

center part of A band where no thin filaments occur

Answer 33

H zone

Question 34

A and I bands refract polarized light differently

Answer 34

A bands ; anisotropic | I bands ; isotropic

Question 35

- in center of H zone | - contains tiny rods that hold thick filaments together

Answer 35

M line

Question 36

- region with only thin filaments | - lies within two adjacent sarcomeres

Answer 36

I Band

Question 37

- springlike molecule that resists overstretching | - extend from z disc to thick filaments to M line

Answer 37

Titin

Question 38

A specialized smooth ER | -interconecting tubules surround each myofibril

Answer 38

sarcoplasmic reticulum

Question 39

some tubules form cross-channels

Answer 39

terminal cisterns

Question 40

released when muscle is stimulated to contract

Answer 40

calcium ions

Question 41

deep invaginations of sarcolemma

Answer 41

t tubules

Question 42

t tubule flanked by two terminal cisterns

Answer 42

triad

Question 43

2 major types of contractions

Answer 43

concentric contraction | eccentric contraction

Question 44

muscle shortens to do work

Answer 44

concentric contraction

Question 45

muscle generates force as it lengthens

Answer 45

eccentric contraction

Question 46

-muscle is stretched by a movement opposite that which contracts it

Answer 46

muscle extension

Question 47

-point where nerve ending and muscle fiber meet

Answer 47

neuromuscular junction

Question 48

located at ends of axons | -stores neurotransmitters

Answer 48

terminal boutons

Question 49

space between axon terminal and sarcolemma

Answer 49

synaptic cleft

Question 50

produce ATP aerobically

Answer 50

oxidative fibers

Question 51

produce ATP anaerobically by glycolysis

Answer 51

Glycolytic fibers

Question 52

skeletal muscle fibers divided into 3 classes

Answer 52

1. slow oxidative fibers 2. fast glycolytic fibers 3. fast oxidative fibers

Question 53

- red slow oxidative fibers - obtain energy from aerobic metabolic reactions - contain large number of mitochondria - contract slow and resistant to fatigue

Answer 53

slow oxidative fibers

Question 54

white fast glycolytic fibers | -contract rapidly and tire quickly

Answer 54

fast glycolytic fibers

Question 55

intermediate fibers - contract quickly - fatigue resistant

Answer 55

fast oxidative fibers

Question 56

-group of inherited muscle destroying disease -affected muscles enlarge with fat and connective tissue -muscles degenerate -types ; ducheene muscular dystrophy myotonic dystrophy

Answer 56

muscular dystrophy

Question 57

pain caused by tightened bands of muscle fibers

Answer 57

myofascial pain syndrome

Question 58

- mysterious chronic-pain syndrome - affects mostly women - symptons ; fatigue, sleep abnormalities, severe musculoskeletal pain, and headache

Answer 58

fibromyalgia

Question 59

muscle tissue develops from

Answer 59

myoblasts

Question 60

muscle wasting

Answer 60

sarcopenia