Physio Chapter 12 Part 1

Question 1

Skeletal muscle attached to bone on each end by _____?

Answer 1

tendons

Question 2

Prime mover of any skeletal muscle movement is called a what muscle?

Flexors and extensors that act on the same joint to produce opposite actions is called a what muscle?

Answer 2

agonist muscle, antagonist muscle

Question 3

Tendon connective tissue extends to form fibrous sheath is called a what?

Connective tissue extends into the body of the muscle.
Composed of columns of muscle fibers.
Each of theses are surrounded by perimysium

Answer 3

epimysium, fascicles

Question 4

When somatic neuron is activated, all the muscle fibers it innervates contract with ____ or _____ contractions

Answer 4

all or none,

Question 5

Ratio of motor neuron: muscle fibers.
Fine neural control over the strength occurs when many small motor units are involved, this is called the?

Larger and larger motor units are activated to produce greater strength, this is called?

Answer 5

innervation ratio, recruitment

Question 6

In regards to motor units, each muscle fiber receives a _____ axon terminal from a somatic neuron.

Each axon can have collateral branches to innervate an ______of fibers.

Answer 6

single, equal number

Question 7

Each myofibril contains ______. There are ____ and _____ filaments

Answer 7

myofilaments, thick and thin

Question 8

Thick filaments are primarily composed of ______ and thin filaments are primarily composed of _______?

Answer 8

myosin, actin

Question 9

Sarcomere Z disc to Z disc, in the middle there are ___ lines. These anchor _____ during contraction.

Answer 9

M, mysoin

Question 10

Elastic protein that runs through the myosin from M line to Z disc.
Contributes to elastic recoil of muscle. This is called what?

Answer 10

Titin

Question 11

Sliding of filaments is produced by the actions of…

Answer 11

cross bridges

Question 12

Cross bridges are part of the myosin proteins that extend out toward _____?
Each myosin head contains an ________?

Answer 12

actin, ATP binding site

Question 13

These bands contain myosin, mover closer and does not shorten during contraction

Distance between A bands of successive sarcomeres.
Decrease in length

Contain only myosin.
Shorten during contraction, are in conjunction with M line

Answer 13

A bands, I Bands, H bands

Question 14

In muscle contraction myosin binding site splits atp to adp, ADP remain bound to _____ until these heads attach to _____?

Answer 14

mysoin, actin

Question 15

In muscle contraction, this pulls actin toward the center of the A band.

Answer 15

Power stroke

Question 16

ADP is released when ____ binds to a fresh ___ at the end of the power stroke.

Answer 16

mysoin, ATP

Question 17

In muscle contraction, release of ADP upon binding to another ATP, causes the ______ bond to break.

Answer 17

cross bridge

Question 18

Only 50% of the cross bridges are attached at any given time, this is called the

Answer 18

synchronous action

Question 19

Regulation of cross bridge attachment to actin due to (2)?

Answer 19

tropomysoin, troponin

Question 20

In relaxed muscle, _______ blocks binding sites on actin

Answer 20

tropomyosin

Question 21

When calcium production is blocked what happens to the muscle?

Answer 21

muscle relaxes

Question 22

In excitation-contraction coupling, ____ diffusion produces end plate potential. + ions are attracted to negative _______. If depolarization is sufficient, threshold occurs, producing an _____.

Answer 22

Na+, plasma membranes, AP

Question 23

In excitation-contraction coupling, ____ travel down sarcolema and T tubules.
SR terminal cisternae release ____ from chemical channels.

Answer 23

APs, Ca

Question 24

In excitation-contraction coupling, Ca is also released through a _______ Ca release.

Answer 24

Calcium induced

Question 25

In excitation-contraction coupling, upon its release Ca attaches to?

Tyropmysoin-troponin complex configuration change occurs, cross bridges attach to _____?

Answer 25

trophonin, actin

Question 26

In muscle relaxation, ____must cease for the muscle to relax?

These channels have to be closed?

ACh must be degraded? yes or no

Answer 26

APs, Ca, yes

Question 27

Muscle is stimulated with a single electrical shock (above threshold).
Quickly contracts and then relaxes.
Increasing stimulus increases the strength of the ____ (up to maximum).

Answer 27

twitch

Question 28

If second electrical shock is administered before complete relaxation of muscle

Answer 28

summation

Question 29

Stimulator delivers an increasing frequency of electrical shocks.
Relaxation period shortens between twitches.
Strength of contraction increases

Answer 29

incomplete tetanus

Question 30

Fusion frequency of stimulation.
No visible relaxation between twitches.
Smooth sustained contraction

Answer 30

complete tetanus

Question 31

Staircase effect.
Electrical shocks are delivered at maximum voltage.
Each shock produces a separate, stronger twitch (up to maximum).
Due to increase in intracellular Ca2+.
Represents “warm-up.”

Answer 31

Treppe

Question 32

Force of contraction remains constant throughout the shortening process.
Velocity of muscle shortening decreases as load increases

Answer 32

isotonic contraction

Question 33

Length of muscle fibers remain constant, if the number of muscle fibers activated is too few to shorten the muscle.
Velocity of shortening is 0

Answer 33

isometric contraction

Question 34

Force exerted on a muscle to stretch, it is greater than the force of muscle contraction.
Muscle will lengthen as it contracts.

Answer 34

eccentric contraction

Question 35

This is what kind of curve?

Inverse relationship between force opposing muscle contraction and velocity of muscle shortening.

Answer 35

force-velocity curve

Question 36

in regards to the series-elastic component, non-contractile tendons and connective tissue absorb tension as the _____?

Answer 36

muscle contracts

Question 37

In regards to the series-elastic component, tnedons first must be pulled tight, before the muscle contraction results in ______?
Tendons have elasticity and display _____.

Answer 37

shortening, recoil (spring back to resting length)

Question 38

Strength of muscle contraction influenced by:
Frequency of ______.
Thickness of each ______.
Initial ______ of muscle fiber

Answer 38

stimulation, muscle fiber, length

Question 39

Talking about length-tension relationship,

Length which can generate maximum force is called what?

Few cross bridges can attach is called what?

No cross bridges can attach to actin is called what?

Answer 39

ideal resting length, overlap too small, no overlap