Muscle physiology and anatomy

Question 1

Types of muscles

Answer 1

Cardiac, skeletal, smooth

Question 2

Smooth Muscle location

Answer 2

Internal organs

Question 3

Cardiac Muscle location

Answer 3

Heart only

Question 4

Skeletal Muscle location

Answer 4

Skeleton. Bones by tendon

Question 5

Striated muscles

Answer 5

Skeletal and Cardiac

Question 6

Not a striated muscle

Answer 6

Smooth

Question 7

Muscle with branches

Answer 7

Cardiac

Question 8

Muscle(s) without branches

Answer 8

Skeletal and Smooth

Question 9

Which muscle(s) are involuntary?

Answer 9

Cardiac and Smooth

Question 10

Which muscle is voluntary

Answer 10

Skeletal

Question 11

The 5 functions of muscles

Answer 11

1. Movement,
   2.Posture & body position
2. Support soft tissue
   4.Guards body entrances and exits
3. Maintain body temperature

Question 12

Actin

Answer 12

Found within thick filaments

Question 13

Myosin

Answer 13

Found in thin filaments

Question 14

What is a sacromere

Answer 14

Basic contractile unit of muscle fiber

Question 15

A Band

Answer 15

Region with thick(and thin) filaments

Question 16

I Band (i)

Answer 16

Region without thick filaments

Question 17

H Zone

Answer 17

Region without thin filaments

Question 18

M Line

Answer 18

Region in the center of the thick filaments purely thick filaments

Question 19

Step one of Action potential NMJ (Neuromuscular junction)

Answer 19

Action potential is sent from the brain,relasing ACh (acetylcholine into the synaptic cleft. the ACh realesed by neurons tells muscles to move…

Question 20

Step two of NMJ

Answer 20

ACh binds to ACh receptors on the sarcolemma.Sodium ions move into the sarcoplasm-> action potential in the sacrolemma..

Question 21

Step three of NMJ

Answer 21

Action potential goes down the T tubules. The action potential causes the cisternae to release calicum ion. Muscle contractions start when the cisternae releases calcium.

Question 22

Cross Bridge cycling step one

Answer 22

Ca2+ is relased by the sacroplasmic reticulum..

Question 23

Cross Bridge cycling step two

Answer 23

Ca2+ bidns to the troponin

Question 24

Cross Bridge cycling step three

Answer 24

The binding of Ca2+ causes troponin to change shape and roll tropmyosin off the myosin-binding sites

Question 25

Cross Bridge cycling step four

Answer 25

The myosin head cocks, forming a cross-bridge between the mysoin head and the myosin binding site.

Question 26

Cross Bridge cycling step five

Answer 26

Myosin pulls actin toward the M-line. This is called power-stroke

Question 27

Cross Bridge cycling step six

Answer 27

ATP binds to myosin, allowing it to break the cross-bridge. Steps 4-6 repeat as long as Ca2+ and ATp are present.

Question 28

Myofibrils have repeating units called…

Answer 28

Sacromeres!

Question 29

In a muscle cell, the plasma membrane is called the…?

Answer 29

Sacrolemma

Question 30

In a muscle cell, the cytoplasm is called the ___

Answer 30

Sacroplasm

Question 31

Motor Units

Answer 31

The motor unit is a motor neuron and all of the muscle fibers it innervates (stimulates)

Question 32

Motor Neurons

Answer 32

are cells in the brain and spinal cord that allow us to move, speak, swallow and breathe by sending commands from the brain to the muscles that carry out these functions.

Question 33

Fine motor control

Answer 33

the coordination of muscles, bones, and nerves to produce small, exact movements.

Question 34

Gross motor control

Answer 34

The ability to make large, general movements (such as waving an arm or lifting a leg)

Question 35

Recruitment

Answer 35

the process of increasing the number of motor units to participate in muscle contraction

Question 36

Muscle contractions

Answer 36

the tightening, shortening, or lengthening of muscles when you do some activity.

Question 37

Tension

Answer 37

the condition where one or more muscles remains semi-contracted for a prolonged period.

Question 38

Twitch

Answer 38

A single stimulus-contraction-relaxation sequence of a muscle fiber.

Question 39

Summation

Answer 39

refers to the fact that if a second stimulus arrives before the relaxation phase has ended, a second, more powerful twitch occurs.

Question 40

Tetanus

Answer 40

A sustained and continuous contraction when there’s a high frequency of stimulus.

Question 41

Isotonic muscle contraction

Answer 41

A muscular contraction in which the length of the muscle changes.

Question 42

Isometric muscle contraction

Answer 42

a muscle contraction without motion.

Question 43

Isotonic eccentric

Answer 43

involves the muscle lengthening whilst it is under tension.

Question 44

isotonic concentric

Answer 44

a type of muscle contraction in which the muscles shorten while generating force.

Question 45

Size principle

Answer 45

as more force is needed, motor units are recruited in a precise order according to the magnitude of their force output,

Question 46

Phases in Muscle Fiber Stimulation (Single)
Latent phase

Answer 46

1. Action potential starts → calcium released
   No tension though because contraction hasn’t happened yet

Question 47

Phases in Muscle Fiber Stimulation (Single)
Contraction phase

Answer 47

2.
Tension peaks because cross-bridge activity is happening

Question 48

Phases in Muscle Fiber Stimulation (Single)
Relaxation phase

Answer 48

3.
Muscle tension decreases because calcium levels decrease
Number of cross-bridges decreases

Question 49

Compression

Answer 49

If the sensation you are feeling is coming from tissues being pressed into each other, this is compression. It could include the feeling of one bone rubbing on another.