Muscles 1

Question 1

In all muscle types, the generation of force depends on…

Answer 1

the conversion of chemical energy (ATP)

Question 2

Three kinds of muscle

Answer 2

skeletal, cardiac, smooth

Question 3

skeletal muscles

Answer 3

• primarily voluntary

- multinucleated

Question 4

cardiac muscles

Answer 4

• primarily involuntary

- uninucleated

Question 5

smooth muscle

Answer 5

• primarily involuntary

- uninucleated

Question 6

Which muscle type has no striations?

Answer 6

smooth

Question 7

skeletal muscles attach to bones by…

Answer 7

tendons

Question 8

origin

Answer 8

closest to trunk or to more stationary bone

Question 9

insertion

Answer 9

more distal or more mobile attachment

Question 10

flexor

Answer 10

brings bones together

Question 11

extensor

Answer 11

moves bones away

Question 12

40% of total body weight…

Answer 12

skeletal muscle

Question 13

muscle cell=

Answer 13

muscle fiber

Question 14

cell membrane=

Answer 14

sarcolemma

Question 15

cytoplasm=

Answer 15

sarcoplasm

Question 16

modified endoplasmic reticulum=

Answer 16

sarcoplasmic reticulum

Question 17

muscle fascicle

Answer 17

bundle of muscle fibers

Question 18

muscle fibers

Answer 18

bundle of myofibrils

Question 19

striations

Answer 19

correspond to ordered arrays of thick and thin filaments within myofibrils

Question 20

one sarcomere

Answer 20

from a z-disk to another z-disk

Question 21

thin filaments

Answer 21

f-actin, tropomyosin, troponin complex

Question 22

f-actin

Answer 22

double stranded alpha helical polymer of G-actin molecules; contains binding site for thick filaments

Question 23

tropomyosin

Answer 23

two identical alpha helices the coil and sit around actin strands; regulate binding of myosin to actin

Question 24

troponin complex

Answer 24

TnT, TnC, TnI; situated approx. every 7 actin molecules

Question 25

troponin T

Answer 25

binds to a single molecule of tropomyosin

Question 26

troponin C

Answer 26

Calcium binding site

Question 27

troponin I

Answer 27

under resting conditions is bound to actin, inhibiting contraction

Question 28

thick filaments

Answer 28

consists of a bundle of myosin molecules

Question 29

myosin

Answer 29

two intertwined heavy chains

Question 30

heavy chains

Answer 30

contains two light chains

Question 31

regulatory lights chain

Answer 31

regulates ATPase activity of myosin

Question 32

essential light chain

Answer 32

stabilizes myosin head

Question 33

Myosin head contains…

Answer 33

region for binding actin and a site for binding and hydrolyzing ATP (ATPase)

Question 34

titin

Answer 34

a protein intending from M line to Z line; involved in stabilization and elastic recoil of muscle

Question 35

nebulin

Answer 35

a protein that wraps around the thin filament; regulate length of thin filaments and contribute to structural integrity of myofibrils

Question 36

Z disk

Answer 36

attachment site for thin filaments

Question 37

I bands

Answer 37

lightest band of sarcomere; region occupied only by thin filaments

Question 38

A band

Answer 38

darkest band of sarcomere; encompasses entire length of thick filaments and area where thin and thick overlap

Question 39

H zone

Answer 39

central region of A band with only thick filaments

Question 40

M line

Answer 40

attachment site for thick filaments

Question 41

glucose within the sarcoplasm

Answer 41

stored as glycogen

Question 42

sliding filament model

Answer 42

muscle contraction - H zone and I band shorten

Question 43

tension

Answer 43

force generated by a contracting skeletal muscle

Question 44

neuromuscular junction

Answer 44

point of synaptic contact between somatic motor neuron and individual muscle fibre

Question 45

excitation-contraction coupling

Answer 45

an action potential initiated in skeletal muscle fibre resulting in an increase in intracellular Ca2+