ch 10 - lecture review

Question 1

epimysium

Answer 1

layer of collagen fibers that surrounds entire muscle and separates it from surrounding to tissues

Question 2

perimysium

Answer 2

surrounds fascicles

Question 3

endomysium

Answer 3

surrounds individual muscle cells

Question 4

what is the organization of a muscle tissue

Answer 4

Myofilament
Myofibril
Muscle fiber
Fasicle
Muscle tissue

Question 5

myofilament

Answer 5

bundles of contractile protein filaments

Question 6

myofibril

Answer 6

collections of myofilaments that are responsible for muscle contraction

Question 7

muscle fiber

Answer 7

muscle cell

Question 8

fascicle

Answer 8

bundle of muscle fiber

Question 9

muscle tissue

Question 10

2 types of myofilament

Answer 10

actin (thin) and myosin (thick)

Question 11

sarcolemma

Answer 11

plasma membrane of a muscle fiber

Question 12

sarcoplasm

Answer 12

cytoplasm of a muscle fiber

Question 13

transverse tubules (t-tubules)

Answer 13

narrow tubes continuous with the sarcolemma, which extend from the surface of the muscle fiber deep into the sarcoplasm

Question 14

sarcomere

Answer 14

repeating structural and functional units of a myofibril

Question 15

sarcoplasmic reticulum

Answer 15

tubular network similar to smooth ER that surrounds each myofibril and forms terminal cisternae

Question 16

terminal cisternae

Answer 16

store calcium and attach to T tubules

Question 17

triad

Answer 17

2 cisternae plus a T tubule

Question 18

A bands

Answer 18

dark bands, which run the length of the thick filaments

Question 19

subdivisions of A band

Answer 19

M line
H band
zone of overlap

Question 20

M line

Answer 20

vertical line in center of A band; contains proteins that stabilize the position of the thick filaments

Question 21

H band

Answer 21

made only of thick filaments and extends on either side of the M line

Question 22

I band

Answer 22

light bands that contain only thin filaments

Question 23

which segments in a sarcomere, shorten during contraction?

Answer 23

H and I bands

Question 24

the 4 different types of protein that make up a myofibril.

Answer 24

Actin
Myosin
Tropomyosin
troponin

Question 25

Which protein does the myosin head bind to during contraction?

Answer 25

actin

Question 26

which ion helps in contraction process

Answer 26

calcium

Question 27

sliding filament theory

Answer 27

during a contraction, thin filaments slide toward the center of the sarcomere (M line) alongside the thick filaments

Question 28

Excitation- Contraction coupling?

Answer 28

the link between the generation of an action potential in the sarcolemma and the start of muscle contraction

Question 29

neuromuscular junction

Answer 29

the synapse between a motor neuron and a skeletal muscle fiber

Question 30

parts of nmj

Answer 30

axon terminal: expanded end of the axons of the motor neuron

motor end plate: folded membrane of the skeletal muscle fiber at the NMJ

synaptic cleft: space between the axon terminal and motor end plate

Question 31

motor unit

Answer 31

a motor neuron and all the muscle fibers it controls

Question 32

thin filament contain

Answer 32

• filamentous actin (f-actin)
• nebulin
• tropomyosin
• troponin

Question 33

filamentous actin (f-actin)

Answer 33

twisted strand composed of 2 rows of G-actin molecules

Question 34

active sites on G-actin bind to

Answer 34

myosin

Question 35

nebulin

Answer 35

holds the F actin strands together

Question 36

tropomyosin

Answer 36

covers the active sites on G-actin and prevents actin-myosin interaction

Question 37

troponin

Answer 37

globular protein that holds tropomyosin in place and binds to calcium ions

Question 38

contraction steps (6)

Answer 38

1. brain stimulates muscle contraction + releases action potential
2. terminal cisternae releases Ca to bind to troponin
3. troponin becomes flat when Ca binds
4. tropomyosin slips off which exposes active sites on G-actin
5. myosin heads binds to exposed active sites
6. power stroke/musclencontracts

Question 39

Tendon

Answer 39

Bone to muscle

Question 40

aponeurosis

Answer 40

blending of epi, peri, and endomysium that forms a broad sheet at the end of a muscle

Question 41

thin filament consists of

Answer 41

pair of F actin molecules twisted together