Elina_Physiology_Skeletal Muscle

Front 1

Ultrastructure of aMyofibril
A muscle cells called are

Back 1

muscle fibers

Front 2

Ultrastructure of aMyofibril
Muscle fibers consist of ...

Back 2

of myofibrils,

Front 3

Ultrastructure of aMyofibril
A myofibril can be subdivided into..

Back 3

individual sarcorneres. A sarcomere is demarked by
a Z lines.

Front 4

Ultrastructure of aMyofibril
A sarcomere is demarked by?

Back 4

A sarcomere is demarked by
a Z lines.

Front 5

Ultrastructure of aMyofibril
Sarcomeres are composed of

Back 5

Sarcomeres are composed of thin and thick filaments

Front 6

Ultrastructure of aMyofibril
Что будет с А and I band во время сокращения?

Back 6

Contraction causes no change in the length of the A band, a shortening of the I band,
and a shortening in the H zone (band).

Front 7

Ultrastructure of the Sarcoplasmic Reticulum
The sarcoplasmic reticulum is part of ?

Back 7

The sarcoplasmic reticulum is part of the internal membrane system

Front 8

Ultrastructure of the Sarcoplasmic Reticulum
function of The sarcoplasmic reticulum?

Back 8

function of which is to store calcium

Front 9

Ultrastructure of the Sarcoplasmic Reticulum The sarcoplasmic reticulum
Where the most of the calcium is stored?

Back 9

In skeletal muscle, most of the calcium is stored in the terminal cisternae close
to the T-tubular system.

Front 10

Organization· of the Thin and Thick Filaments
Actin is?

Back 10

• The structural protein of the thin filament
• Possesses the attachment sites for the cross-bridges

Front 11

Organization· of the Thin and Thick Filaments
Tropomyosin is?

Back 11

Tropomyosin
• Covers or makes the attachment sites of the cross-bridges unavailable in resting muscle

Front 12

Organization· of the Thin and Thick Filaments
Troponin is?

Back 12

Composed of three subunits: troponin-T, which binds to tropomyosin; troponin-I,
which inhibits myosin binding to actin; and troponin-C, which binds to calcium

Front 13

Organization· of the Thin and Thick Filaments
Что происходит во время покоя мыщцы,

Back 13

кальций не связывается с тропонинои С и место для прикрепления с миозином у актина закрыт тропомиозином

Front 14

Organization· of the Thin and Thick Filaments
что происходит во время прикрепления са к тропонину С?

Back 14

When calcium binds to troponin, the troponin-tropomyosin complex moves, making
the attachment sites for the cross-bridges on the actin available for cross-linking with
myosin cross-bridges.

Front 15

Organization· of the Thin and Thick Filaments
when is Contraction terminated? (cycling is terminated)

Back 15

Contraction is terminated (cycling is terminated) when calcium is removed from the
troponin.

Front 16

Organization· of the Thin and Thick Filaments
Myosin?

Back 16

Possesses the cross-bridges that can attach to the actin of the thin filaments
Cross-bridges possess ATPaseactivity.

Front 17

Organization· of the Thin and Thick Filaments
на что тратиться АТФ?

Back 17

атф необходимо для рассоединения Са от тропонина и для мех сокращение мыщцы

Front 18

Organization· of the Thin and Thick
что происходит с АТФ в конце цикла cross-bridges?

Back 18

Every time a cross-bridge completes a single cycle, one ATP is hydrolyzed. This provides the
energy for the mechanical aspects of contraction, that is, active shortening and/or the development
of active tension.

Front 19

Organization· of the Thin and Thick
Когда остановится цикл cross-bridges?

Back 19

Withdrawal of Ca2
+: cycling stops at position 1 (normal resting muscle)
or
ATP is depleted: cycling stops at position 3 (rigor mortis). This would not occur under
physiologic conditions.

Front 20

I"trace!!u!ar Contraction-Relaxation Steps
До каких структур распространяется потерциал дейсваия при нейромышечной передаче?

Back 20

The action potential initiated at the neuromuscular junction travels over the surface of the skeletal
muscle cell and down the T tubules, where it terminates

Front 21

I"trace!!u!ar Contraction-Relaxation Steps
распространияется ли Потенциал Действия вдоль поверхности саркоплазсмтрического ретикулума?

Back 21

The action potential does not spread
across the surface of the sarcoplasmic reticulum, which is an internal membrane system

Front 22

I"trace!!u!ar Contraction-Relaxation Steps
какие рецепторы в Т-тубулярной мемране актирируются?

Back 22

Dihydropyridine receptors in the T-tubular membrane are activated.

Front 23

I"trace!!u!ar Contraction-Relaxation Steps
Dihydropyridine receptors,их функция?

Back 23

These receptors function
as voltage sensors that pull the junctional foot processes away from the ryanodine calciumrelease
channels in the sarcoplasmic reticulum

Front 24

I"trace!!u!ar Contraction-Relaxation Steps
ПРи разрушении АТФ для чего энергия?

Back 24

The ATPbroken down on the cross-bridges produces energy that is utilized for the
production of active tension and/or the active shortening of the muscle.

Front 25

intracellu!ar Contraction-Relaxation Steps
Contraction is terminated (cycling is terminated) by?

Back 25

Contraction is terminated (cycling is terminated) by the pumping of the calcium back into
its storage depot inside the sarcoplasmic reticulum. This is an energy-dependent active
process.

Front 26

WHAT Two ATPases are involved in contraction:?

Back 26

TwoATPasesare involved in contraction:
- Myosin ATPase: Supplies the energy for the mechanical aspects of contraction
- Sarcoplasmic endoplasmic reticulum calcium-dependent AI'Pasc (SERCA):
Supplies the energy to terminate contraction

Front 27

использяуется ли extracellular calcium и voltage-gated calcium
channels для сокращения?

Back 27

• No extracellular calcium is involved.
• The surface membrane of skeletal muscle does not possess voltage-gated calcium
channels (this is not true for cardiac and smooth muscle).

Front 28

Что происходит при увелечении частоты потенциала действия?

Back 28

Increasing the frequency of action potentials causes the release of more calcium from
the sarcoplasmic reticulum and the cycling of more cross-bridges for a longer period
of time. This increases the magnitude of the mechanical response. This is summation.

Front 29

за счет чего протсходит судорога,

Back 29

из-за избытка свободного Са,и более продолжительно цикла сокращения.

Front 30

почему судороги присуствуют в скелетных мыщцах и отсутсвуют в сердечных?

Back 30

из-за периода относительной рефрактерности,который наступает в скелетной мышцы в начале реполяризации,а в сердечной,в конце стадии

Front 31

Skeletal Muscle
Mechanics

Preload is?

Back 31

Preload is the load on a muscle in a relaxed state that is, prior to contraction.

Front 32

Skeletal Muscle
Mechanics
PRELOAD AND AFTERLOAD
что происходит с мыщцей во время Preload?

Back 32

the muscle to stretch.

Front 33

Skeletal Muscle
Mechanics
PRELOAD AND AFTERLOAD
чем больше Preload,тем....

Back 33

The greater the preload added, the greater the stretch of
the muscle

Front 34

Skeletal Muscle
Mechanics
PRELOAD AND AFTERLOAD
что просиходит с саркомером при увелечении Preload?

Back 34

The
greater the preload, the greater the prestretch of the sarcomere.

Front 35

PRELOAD AND AFTERLOA
what is passive tension?

Back 35

If a 2-g weight is suspended from a
muscle, a 2-g force also develops within that muscle. This force is the passive tension.

Front 36

PRELOAD AND AFTERLOAD
как зависит passive tension от preload?

Back 36

The greater the preload, the greater the passive tension in the muscle

Front 37

PRELOAD AND AFTERLOAD
Когда лучше всего измерять длину саркомера?

Back 37

The best measures of preload of any muscle type arc those that most directly relate to sarcomere
length before the muscle becomes active.

Front 38

PRELOAD AND AFTERLOAD, there are two types of tension:In muscle mechanics

Back 38

In muscle mechanics, there are two types of tension:
Passive tension: produced by preload prior to contraction
• Active tension: produced by cross-bridge cycling during the process of contraction

Front 39

PRELOAD AND AFTERLOAD Afterload is?

Back 39

Afterload is the force the muscle must develop to shorten and lift the load.

Front 40

If the muscle must develop a force of 100lb.o lift then the afterload is ?

Back 40

If the muscle must develop a force of 100lb. to lift then the afterload is 100 lb

Front 41

при увелечении пассивного напряжения мышцы что происходит с длинной мышцы,

Back 41

увеличивается

Front 42

Isometric Tetanic Contraction of the Isolated Skeletal Muscle
что происходит с длиной мышцы во время изометрического сокращения?

Back 42

During an isometric contraction, the cross-bridge cycling will produce active tension, but the
overall muscle length will not change.
The muscle does not shorten and lift the afterload because the afterJoad is greater than the total
tension in the muscle during contraction.

Front 43

где Са хранится в скелетной мыщце?

Back 43

In skeletal muscle, all of the free calcium is from calcium stored in the sarcoplasmic
reticulum.

Front 44

Active tension development
The active tension developed during a tetanic isometric contraction is....

Back 44

The active tension developed during a tetanic isometric contraction is proportional to the number
of these cross-bridges that cycle.

Front 45

как зависит потенциал действия от cross-bridges that cycle ?

Back 45

The more cross-bridges that cycle,the greater the developed active tension.

Front 46

The total tension in the active muscle is?

Back 46

The total tension in the active muscle is the passive or preload tension plus the active tension.

Front 47

Maximum velocity (Vmax) is determined by?

Back 47

Maximum velocity (Vmax) is determined by the muscle's ATPaseactivity. It
is the ATPase activity that determines a fast versus a slow muscle.

Front 48

Maximum force generated by a muscle (or maximum load lifted by a
muscle) is determined by ?

Back 48

Maximum force generated by a muscle (or maximum load lifted by a
muscle) is determined by muscle mass or,the number
of motor units activated during contraction

Front 49

what is White Muscle?

Back 49

White Muscle
Generally, large (powerful) muscle that is utilized short term, e.g., leg muscles of a sprinter,
ocular muscles of the eye

Front 50

Major characteristics of white muscle?

Back 50

Major characteristics
• Large mass per motor unit
• High ATPase activity (fast muscle)
• High capacity for anaerobic glycolysis
• low myoglobin

Front 51

Red Muscle is?

Back 51

Red Muscle
Generally smaller (less powerful) muscle utilized long term (endurance muscle), e.g., postural
muscle

Front 52

Major characteristics of Red Muscle are?

Back 52

Major characteristics
• Small mass per motor unit
• Lower ATPase activity (slower muscle)
High capacity for aerobic metabolism (mitochondria), which is more efficient than
anaerobic glycolysis
High myoglobin (imparts red color)

Front 53

В чем отличие Skeletal Cardiac Smooth по исчерсенности мышечного волокна?

Back 53

Skeletal Cardiac Smooth
Striated Striated Nonstriated

Front 54

В чем отличие Skeletal Cardiac Smooth ,саркомеры

Back 54

Actin and myosin organized into
sarcorneres в скелетной и сердечной ,и не организованы в гладкой

Front 55

В чем отличие Skeletal Cardiac Smooth в соединении между клетками

Back 55

Sarcolemma lacks Junctional complexes-скелетная Gap junctions between fibers-сердечная и гладкая

Front 56

В чем отличие Skeletal Cardiac Smooth ,иннервация волокна

Back 56

Each fiber innervated -скелетная Electrical syncytium -сердечная и гладкая

Front 57

В чем отличие Skeletal Cardiac Smooth ,что связывается с кальцием,

Back 57

Troponin to bind calcium -скелетная,сердечная
Calmodulin to bind
calcium -гладкая

Front 58

В чем отличие Skeletal Cardiac Smooth ,АТФазная активность

Back 58

High ATPase activity (fast muscle) -скелетная
Intermediate ATPase -сердечная
Low ATPase activity
activity (slow muscle)-гладкая

Front 59

В чем отличие Skeletal Cardiac Smooth, sarcoplasmic reticulum

Back 59

Extensive sarcoplasmic reticulum
-скелеьная,
Intermediate sarcoplasmic reticulum -сердечная,
Limited
sarcoplasmic reticulum -гладкая

Front 60

отличие серднчной,гладкой и скелеьной, Т тубулы

Back 60

T tubules form triadic contacts with reticulum at A-I junctions-скелетная
T tubules form dyadic contact with reticulum near Z lines -сердечная
Lack T tubules,
SR controlled by
second messengers-гладкая

Front 61

отличие серднчной,гладкой и скелеьной,
кальцевые каналы

Back 61

Surface membrane lacks calcium channels-скелетная,
Voltage-gated calcium channels -сердечная и гладкая