Muscle Tissue

Question 1

Skeletal muscle

Answer 1

Connected to bones, voluntary, striated, and multi-nucleated

Question 2

Cardiac muscle

Answer 2

Located in the heart, involuntary, striated, and mono-nucleated

Question 3

Smooth muscle

Answer 3

Located in hollow organs, involuntary, non-striated, and mono-nucleated

Question 4

Plasticity

Answer 4

Muscle mass can increase based on activity. They have the ability to increase in volume (not number of muscle fibers)

Question 5

Atrophy

Answer 5

Muscle fiber diameter decreases when they are inactive

Question 6

Hypertrophy

Answer 6

Muscle fiber diameter increases after continuous activity

Question 7

Layers of connective muscle tissue

Answer 7

Epimysium, Perimysium, Endomysium

Question 8

Sarcolemma

Answer 8

plasma membrane of muscle cell

Question 9

Sarcoplasmic reticulum

Answer 9

Smooth ER of the muscle cell

Question 10

Titin

Answer 10

Protein that provides the force (“spring”), that contributes to muscle contraction and expansion

Question 11

Distrophin

Answer 11

Protein that cross links with actin and establishes contact w/ cytoskeleton and ECM.

Question 12

Cisternae

Answer 12

Located in the sarcoplasmic reticulum. They form around the microfibrils and are divided by T tubules to form sections of the sarcomere

Question 13

Transverse (T) tubules

Answer 13

protrusions toward the inside of the fiber from the SR that provide support and adds to the cellular structure

Question 14

Triad

Answer 14

Located in the A-I junction of the myofibril, one T tubule is surrounded by 2 cisternae. They play a role in the release of calcium during the transmission of a nerve impulse.

Question 15

Actin

Answer 15

Thin filaments

Question 16

Myosin

Answer 16

Thick filaments

Question 17

Z line

Answer 17

Form the ends of one sarcomere unit. Actin filaments are attached

Question 18

I band

Answer 18

only actin filaments (thin)

Question 19

H zone

Answer 19

only myosin filaments (thick)

Question 20

M line

Answer 20

middle line myosin is linked with accessory proteins

Question 21

A band

Answer 21

actin and myosin overlap

Question 22

Tropomyosin

Answer 22

filament protein, when calcium binds to TnC, tropomyosin moves to reveal the actin binding sites

Question 23

TnT

Answer 23

Strongly binds to tropomyosin

Question 24

TnI

Answer 24

Inhibits actin-myosin interaction

Question 25

TnC

Answer 25

Has the capacity to bind Ca2+ and changes the conformation of the complex

Question 26

Junctional folds

Answer 26

Forms a wavy membrane around an area of the sarcolemma which contains acetylcholine receptors

Question 27

Cholinesterase

Answer 27

Breaks down acetylcholine so there is not overstimulation of muscle contraction

Question 28

Functions of muscle fibers

Answer 28

Proprioception (muscle sensory), muscle tone, and reflexes

Question 29

Red fibers

Answer 29

Type I, slow twitch

Question 30

White fibers

Answer 30

Type II, fast twitch

Question 31

Intermediate fibers

Answer 31

Have properties of both red and white fibers

Question 32

Intrafusal fibers

Answer 32

Nuclear chain fibers and nuclear bag fibers

Question 33

Extrafusal fibers

Answer 33

Red, white, and intermediate fibers

Question 34

Sinoatrial node

Answer 34

Pacemaker of the heart, generates impulses

Question 35

Purkinje fibers

Answer 35

Muscle cells in the heart, depolarizes the contractile cells of both ventricles

Question 36

Natriuretic peptides

Answer 36

Maintains blood pressure in the heart

Question 37

Zonula adherens

Answer 37

Tight junctions in cardiac muscle

Question 38

Macula adherens

Answer 38

Desmosomes in cardiac muscle

Question 39

Caveolae

Answer 39

Located on the surface of smooth muscle that isinvolved in sequestering Ca2+

Question 40

Multi-unit smooth muscle

Answer 40

Loosely packed smooth muscle that is richly innervated for rapid contractions (large arteries)

Question 41

Visceral smooth muscle

Answer 41

Densely packed smooth muscle that is poorly innervated for slow contractions

Question 42

Varicosities

Answer 42

regions on nerves that contain neurotransmitters at points where they can be released onto smooth muscle for innervation