Skeletal Muscle Fibers

Question 1

A sheath of fibrous elastic tissue that surrounds an entire muscle

Answer 1

Epimysium

Question 2

A sheet of connective tissue surrounding bundles of muscle fibers 

Answer 2

Perimysium

Question 3

A layer of areolar connective tissue that ensheaths individual muscle fibers

Answer 3

Endomysium

Question 4

Largest to smallest skeletal muscle fiber structure 

Answer 4

Muscle belly, epimysium, perimysium, endomysium, muscle fiber (cell)

Question 5

A bundle of muscle fibers

Answer 5

Fascicles

Question 6

Beneath the endomysium, muscle fibers are surrounded by a plasma, membrane, known as

Answer 6

Sarcolemma

Question 7

special type of smooth ER that surrounds myofibrils and stores Ca2+ for release during muscle contraction

Answer 7

Sarcoplasmic reticulum

Question 8

Passes electrical signals, invagination of the sarcolemma and interrupts the sarcoplasmic reticulum surrounding myofibrils

Answer 8

Transverse tubules (T Tubules)

Question 9

Enlargements of sarcoplasmic reticulum on sides of T-Tubules

Answer 9

Terminal cisternae

Question 10

T tubule +2 terminal cisternae 

Answer 10

Triad

Question 11

Thick filaments are made out of

Answer 11

Myosin

Question 12

Thin filaments are made of

Answer 12

Actin

Question 13

binds Ca2+ to displace tropomyosin to allow contraction

Answer 13

Troponin

Question 14

Covers actin binding sites

Answer 14

Tropomyosin

Question 15

thick and thin filaments

Answer 15

A band

Question 16

midline section of A band,
only thick filaments

Answer 16

H zone

Question 17

middle line of A band, hold thick filaments in position

Answer 17

M line

Question 18

Only thin filaments

Answer 18

I band

Question 19

both thin and elastic filaments anchor to these, define the boundaries of the sarcomere

Answer 19

Z discs

Question 20

The myosin head moves toward the M line, pulling the actin along with it. As the actin is pulled, the filaments move approximately 10 nm toward the M line.

Answer 20

Powerstroke

Question 21

Which are the only two in the sarcomere structure that change in length 

Answer 21

H zone and I band