Foreman 4

Front 1

The types of muscle are

Back 1

smooth and striated

Front 2

The types of striated muscle are

Back 2

skeletal and cardiac

Front 3

Skeletal muscle is regulated by

Back 3

voluntary controls

Front 4

For skeletal muscle, striations are

Back 4

linear

Front 5

The most important skeletal muscle for survival is

Back 5

diaphragm.

Front 6

Cardiac muscle is regulated by

Back 6

the autonomic nervous system

Front 7

For skeletal muscle, striations are

Back 7

branched

Front 8

Smooth muscle is regulated by

Back 8

autonomic, hormonal, and paracrine control

Front 9

For smooth muscle, striations are

Back 9

not present.

Front 10

For skeletal muscle, though ________ stops at birth, fibers can still _______.

Back 10

cell division; increase in size.

Front 11

For skeletal muscle, fascicles are

Back 11

bundles of muscle fibers.

Front 12

Individual muscle cells are multi_______.

Back 12

nucleated

Front 13

Myofibrils are

Back 13

cylindrical bundles of thick and thin filaments that form muscle fibers.

Front 14

A sarcomere is

Back 14

a function unit of the muscle fiber.

Front 15

In a sarcomere, thick filaments are composed of

Back 15

myosin

Front 16

IN a sarcomere, thin filaments are composed of

Back 16

actin.

Front 17

Thick sarcomeric filaments contain

Back 17

cross bridges

Front 18

Cross bridges are composed of

Back 18

heavy and light chain, ATP binding sites, actin binding sites.

Front 19

Thin sarcomeric filaments contain

Back 19

cross-bridge binding sites.

Front 20

A bands are composed of

Back 20

overlapping myosin and actin

Front 21

I bands are composed of

Back 21

actin alone

Front 22

The molecular mechanism of contraction is

Back 22

a sliding filament mechanism

Front 23

The sliding filament mechanism of muscle contraction is

Back 23

1. Shortening of sarcomeres due to thin filaments sliding over thick filaments, 2. I band shortens, but A band length does not change.

Front 24

In shortening of sarcomeres, the thick and thin filaments do not change

Back 24

length.

Front 25

Swinging of cross bridges creates

Back 25

muscle contraction

Front 26

The 4 steps of the cross bridge cycle are

Back 26

1. Energeized cross bridge binds to actin, 2. Phosphate is released and cross bridge rotates (power stroke) and pulls thin filaments towards the center of sarcomere while ADP is released form myosin head, 3. ATP binds to myosin head, cross bridge detaches, 4. Hydrolysis of ATP by ATPase on myosin energizes cross bridge.

Front 27

The role of ATP in cross bridge cycle is

Back 27

1. Hydrolysis of ATP energizes the cycle, 2. Binding of ATP breaks the linkage

Front 28

Lack of ATP in cross bridge cycle produces

Back 28

rigor mortis.

Front 29

Muscle contraction initiates in response to

Back 29

an increase in Ca++

Front 30

The two regulator proteins of the cross bridge cycle are

Back 30

tropomysin and troponin

Front 31

The roles of troponin in cross bridge cycle are

Back 31

1. Bind to tropomysin and holds it over myosin binding site, 2. Contains Ca++ binding sites, 3. Binding of Ca++ to troponin causes conformation change which makes tropomysin move aside and expose myosin binding sites on actin.

Front 32

Action potentials in muscles trigger

Back 32

release of Ca2+ from lateral sacs of the sarcoplasmic reticulum causing contraction.

Front 33

______ help propagate action potential within muscle fibers

Back 33

transverse tubules.

Front 34

Relaxation in muscles occurs when

Back 34

lateral sacs pump Ca2+ out of cytosol using Ca2+-ATPase pump.

Front 35

During relaxation in muscles, the sarcomere

Back 35

extends to its resting length.

Front 36

Ca2+ is concentrated in the sarcoplasmic reticulum via

Back 36

Ca2+ binding proteins.

Front 37

The steps of Ca2+ release in muscle contraction are

Back 37

1. Action potential travels along muscle fiber and activates L-type Ca2+ channels, 2. Conformation change in L-type Ca2+ channels causes activation of ryanodine receptors, 3. Activation of ryanodine receptors causes the release of Ca2+ from the sarcoplasmic reticulum.