Chapter 3 - Muscle Structure And Function

Question 0

Muscle makes up ___-___% (in women) and ___-___ (in men) of body mass

Answer 0

30-35 in women and 42-47 in men

Question 1

Human body consists of _____ muscles

Answer 1

640

Question 2

What are the 3 basic types of muscle?

Answer 2

1) skeletal
2) smooth
3) cardiac

Question 3

What is another name for skeletal muscle?

Answer 3

Striated muscle

Question 4

Skeletal muscle connects the various parts of the skeleton through one or more connective tissue structures called _______

Answer 4

Tendons

Question 5

During muscle _______ skeletal muscle shortens and moves various parts of the skeleton

Answer 5

Contraction

Question 6

How can the required smoothness and speed of muscles be achieved?

Answer 6

Through the graded activation of muscles

Question 7

Are skeletal muscles under voluntary or involuntary control?

Answer 7

Under voluntary control

Question 8

________ involves the assessment of movement and the sequential pattern of muscle activation that that move body segments

Answer 8

Biomechanics

Question 9

What is most skeletal muscle attached to?

Answer 9

Bone

Question 10

What is skeletal muscles contraction responsible for?

Answer 10

Supporting and Moving the skeleton

Question 11

List 4 spots u can find smooth muscle.

Answer 11

1) blood vessels
2) respiratory tract
3) iris of the eye
4) gastro-intestinal tract

Question 12

Are the contractions of smooth muscle slow and uniform?

Answer 12

Yes

Question 13

What are the functions of the smooth muscle?

Answer 13

To alter the activity of various body parts to meet the needs f the body at that time

Question 14

Smooth muscle is fatigue _______

Answer 14

Resistant

Question 15

Activation of smooth muscle is ________

Answer 15

Involuntary

Question 16

Swallowing food in the esophagus uses wave like movements called _____

Answer 16

Peristalsis

Question 17

What kind of muscle has characteristics of both skeletal and smooth

Answer 17

Cardiac muscle

Question 18

What are the functions of cardiac muscle

Answer 18

To provide the contractile activity of the heart

Question 19

Contractile activity can be ______ (like skeletal muscle)

Answer 19

Graded

Question 20

Is very fatigue _______

Answer 20

Resistant

Question 21

Activation of cardiac muscle is ________ (like smooth muscle)

Answer 21

Involuntary

Question 22

What are the 4 components of skeletal muscle?

Answer 22

1) muscle belly
2) muscle fiber bundle
3) muscle fiber
4) filament proteins

Question 23

What is the muscle belly? (Of skeletal muscle)

Answer 23

The “whole” of the muscle is the muscle belly

Question 24

What is the muscle fiber bundle? (Of skeletal muscle)

Answer 24

Muscle fiber bundle is a bunch of fibers bundled together

Question 25

What are muscle fibers? (Skeletal muscle)

Answer 25

Muscle fibers are the individual muscle fibers that make up the bundle

Question 26

Where are filament proteins found in skeletal muscle?

Answer 26

Inside the myofibril

Question 27

Muscle fibers are ______ shaped cells that make up the skeletal muscle

Answer 27

Cylinder

Question 28

Each muscle fiber is made up of a nber of _________

Answer 28

Myofilaments

Question 29

Muscle fibers are surrounded by a connective tissue sheath (membrane) called __________

Answer 29

Sarcolemma

Question 30

Many muscle fibers are enclosed by connective tissue sheath called _______ to form a bundle of fibers

Answer 30

Perimysium

Question 31

What 2 things does each muscle fiber contain?

Answer 31

1) contractile machinery | 2) cell organelles

Question 32

Muscle fibers are activated through nerve impulses via ____ ____ ____

Answer 32

Motor end plate

Question 33

What is a group of muscle fibers activated via the same nerve called?

Answer 33

Motor unit

Question 34

Each muscle fiber has _______ that supply nutrients and eliminate waste

Answer 34

Capillaries

Question 35

What is the agonist (prime mover)?

Answer 35

The muscle or group of muscles producing a desired effect | Eg. The bicep when lifting an object

Question 36

What is the antagonist?

Answer 36

The muscle or group of muscles opposing the action | Eg. The triceps relax when the bicep is working

Question 37

What is the synergist?

Answer 37

The muscles surrounding the joint being moved

Question 38

What are the fixators?

Answer 38

The muscle of group of muscles that steady joints closer to the body axis so that the desired action can occur Muscles that stabilize so you don't dislocate Eg. If you are carrying 45 pounds of weight in your hand your shoulder would pop out if not for the shoulder fixator muscles

Question 39

Sarcomeres are ________ units

Answer 39

Contractile

Question 40

What are the 2 types of protein myofilaments in sarcomeres?

Answer 40

Actin | Myosin

Question 41

What are actin

Answer 41

Thin filament

Question 42

What are myosin

Answer 42

Thick filament

Question 43

Each myosin is surrounded by ___ actin filaments

Answer 43

6

Question 44

Projecting from each myosin are tiny contractile _______ _______.

Answer 44

Myosin bridges

Question 45

What is cross bridge formation?

Answer 45

- a signal comes from the motor nerve activating the fiber - the heads of the myosin filaments temporarily attach themselves to the actin filaments - active action coming from the brain Motor nerve activates fiber causing the myosin to attach to actin

Question 46

What is cross bridge movement?

Answer 46

- similar to the stroking of the para and movement of rowing shell - movement of myosin filaments in relationn to actin filaments - shortening of the sarcomere - shortening of each sarcomere is additive

Question 47

Sarcomeres should be _____ distance apart

Answer 47

Optimal

Question 48

What happens if the sarcomeres are stretched farther apart than optimal distance?

Answer 48

Then fewer cross bridges can form which means less force is produced

Question 49

What happens if the sarcomeres are too close together?

Answer 49

Cross bridges then interfere with one another as they form which means less force is produced

Question 50

Maximal force occurs at what 2 things?

Answer 50

Optimal muscle length and joint angle

Question 51

Optimal joint angle occurs at ______ ______ ______

Answer 51

Optimal muscle length

Question 52

The distance between sarcomeres needs to be optimal for what to occur

Answer 52

Maximum exertion of force

Question 53

What are the 2 types of muscle fibers?

Answer 53

Slow twitch fibers and fast twitch fibers

Question 54

Slow twitch fibers

Answer 54

- slow oxidative (type 1) - continuous repition but slowly - suited for repeated contractions during activities requiring a force output of less than 20-25% of max force output - examples: lower power activities, endurance events - have less capacity to generate force

Question 55

Fast twitch fibers

Answer 55

- fast glycolytic (type lla) - fast oxidative glycolytic (type llb) - explosive fibers - for maximum utilization - significantly greater force and speed generating capability than slow twitch fibers - well suited for activities involving high power, low endurance - examples: sprinting, jumping, throwing - you want explosiveness

Question 56

Give a comparison example between fast twitch and slow twitch

Answer 56

Jumping on the spot would be slow twitch while jumping distance would be fast twitch

Question 57

Nervous system can be divided into what 2 parts?

Answer 57

Central nervous system (CNS) | Peripheral nervous system (PNS)

Question 58

What 2 functions can the nervous system be divided into?

Answer 58

Motor and sensory activity

Question 59

Sensory

Answer 59

Collects info from the various sensors located throughout he body and transmits the info to the brain

Question 60

Motor

Answer 60

Conducts signals to activate muscle contraction

Question 61

Most f what happens in our eyes is _______

Answer 61

Sensory

Question 62

Hot receptors cold receptors pressure receptors are all examples of ______

Answer 62

Sensory

Question 63

Motor nerves extend from where to where

Answer 63

From the spinal cord to the muscle fibers

Question 64

How is each muscle fiber activated by motor nerves?

Answer 64

Through impulses delivered via the motor end plate

Question 65

Motor unit

Answer 65

A group of fibers activated via the same nerve

Question 66

True or false: all muscle fibers of one particular motor unit are always of the same fiber type

Answer 66

True

Question 67

What do muscles that need to perform precise movements generally consist of?

Answer 67

A large number of motor units and new muscle fibers

Question 68

What do muscles who need to perform less precise movements generally consist of?

Answer 68

Fewer motor units with many fibers per unit

Question 69

All or none principle

Answer 69

Whether or not a motor unit activates upon the arrival of an impulse depends upon the so called all or none principle

Question 70

What is required to cause the inner cared fibers to contract?

Answer 70

An impulse of a certain magnitude (or strength)

Question 71

Every motor unit has a special _______ that much be reached for such activation to occur

Answer 71

Threshold

Question 72

What is intra muscle coordination

Answer 72

The capacity to apply motor units simultaneously

Question 73

How much of their available muscle fibers can highly trained power athletes (weightlifters, wrestlers and shot putters) activate up to? Vs an untrained person?

Answer 73

85% vs 65%

Question 74

Force deficit

Answer 74

The difference between assisted and voluntarily generated maximal force

Question 75

Inter muscle coordination

Answer 75

The interplay between muscles that generate movement through contraction (agonists) and muscles responsible for opposing movements (antagonists)

Question 76

The greater the participation of muscles and muscle groups the higher the what?

Answer 76

The higher the importance of inter muscle coordination

Question 77

Prime mover is controlled by ______

Answer 77

Antagonist

Question 78

The greater the participation, the greater the _________

Answer 78

Functionality

Question 79

Individuals performance improvements occur through a process of _________ _________ which is reflected on the body's increased strength

Answer 79

Biological adaptation

Question 80

What does adaptation of muscles depend on?

Answer 80

Intensity levels used in training and on athletes uniqr biological makeup