Chapter 6- Muscular System

Question 1

What do the prefixes “myo-“, “mys-“ and “sacro-“ refer too?

Answer 1

muscle

Question 2

The Function: Skeletal muscle

Answer 2

Cover’s bone framework

Question 3

Skeletal Muscle: each muscle fibre is enclosed in a connective tissue sheath called…

Answer 3

Endomysium

Question 4

Skeletal muscle: is a fibrous membrane over the endomysium

Answer 4

Perimysium

Question 5

Skeletal Muscle: the perimysium forms a bundle of fibres called a..

Answer 5

Fascicle

Question 6

The Function: Tendons

Answer 6

• Anchors muscles
• Provides durability
• Conserves space

Question 7

Define the Structure: Tendons

Answer 7

Are mostly tough collagenic fibres

Question 8

Name the Structure: Skeletal Muscle

Answer 8

Striated muscle
Voluntary muscle

Endomysium
Perimysium
Fascicle

Question 9

Define: Smooth muscle

Answer 9

Found in the walls of hollow visceral organs

Question 10

Define the Structure: Smooth muscle

Answer 10

Visceral
Non-striated
Involuntary

Question 11

Where is smooth muscle found?

Answer 11

• Stomach
• Urinary bladder
• Respiratory passages

Question 12

The Function: Cardiac Muscle

Answer 12

Propels blood into the blood vessels and to all tissues of the body

Question 13

Define the Structure: Cardiac muscle

Answer 13

Cardiac
Striated
Involuntary

Question 14

The Function: Muscles

Answer 14

1. Produce movement
2. Maintain posture and body position
3. Stabilising Joints
4. Generating heat

Question 15

Name the 4 special functional properties of Skeletal Muscle

Answer 15

1. Irritability/responsiveness
2. Contractility
3. Extensibility
4. Elasticity

Question 16

To contract, Skeletal Muscles Cells must be stimulated by..

Answer 16

Nerve impulses

Question 17

(Nerve Stimulus & Action Potential)

Define: Motor Unit

Answer 17

One neuron and all the skeletal muscle cells it stimulates

Question 18

The neurotransmitter that stimulates Skeletal Muscle Cells is..

Answer 18

Acetycholine (Ach)

Question 19

Define: Graded Response

Answer 19

The whole muscle reacts to stimuli with graded responses, or different degrees of shortening

Question 20

Graded Muscle contractions can be produced 2 ways..

Answer 20

1. Changing the FREQUENCY of muscle stimulation

2. Changing the NUMBER of muscle cells being stimulated

Question 21

Define: Tetanus

Answer 21

When the muscle is stimulated so rapidly that no evidence of relaxation is seen, and
the contractions are completely smooth and sustained

Question 22

Name the 3 sources of Muscle Contraction

Answer 22

1. Phosphorylation of ADP by creatine phosphate
2. Stored ATP
3. ATP generated by glucose oxidation

Question 23

Define: Muscle Fatigue

Answer 23

Is when the muscle is unable to contract even though it is still being stimulated

Question 24

Name possible causes of Muscle Fatigue

Answer 24

• Oxygen deficit

- Ion imbalance (CA2+ Calcuim, K+ Potassium)

Question 25

Name the 2 types of muscle contraction

Answer 25

1. Isotonic contractions

2. Isometric contractions

Question 26

Define: Isotonic contractions

Answer 26

The myofilaments are successful in their sliding movements,

the muscle shortens and movement occurs

Question 27

Give an example: isotonic contraction

Answer 27

bending the knee, bending the arm

Question 28

Define: Isometric contractions

Answer 28

Are contractions where the muscle doesn’t shorten

• Myosin myofilaments are trying to to slide but the muscle is pitted against some more or less immovable object

Question 29

Give an example: Isometric contractions

Answer 29

pushing against a wall with bent elbows, wall doesn’t move, muscles cannot shorten to straighten the elbow

Question 30

Define: Muscle Tone

Answer 30

is a state of continuous partial contractions where the muscle remains firm and healthy while still being voluntarily relaxed

Question 31

Muscles are attached to bones at 2 points..

Answer 31

Origin

Insertion

Question 32

Define: Origin

Answer 32

the immovable or less movable bone

Question 33

Define: Insertion

Answer 33

the movable bone

- when the muscle contracts the insertion moves toward the origin

Question 34

Name the 6 types of Body/Muscle Movements

Answer 34

1. Flexion
2. Extension
3. Rotation
4. Abduction
5. Adduction
6. Circumduction

Question 35

Give an example: Flexion

Answer 35

Bending the elbow (hinge joint)

Question 36

Give an example: Extension

Answer 36

Straightening the elbow

Question 37

Give an example: Rotation

Answer 37

Shake the head “No” (ball and socket)

Question 38

Give an example: Abduction

Answer 38

Moving arm away from the body

Question 39

Give an example: Adduction

Answer 39

Moving arm towards the body

Question 40

Give an example: Circumduction

Answer 40

Making circular movements with arm

Question 41

Give an example: Dorsiflexion

Answer 41

lifting toes towards the shin

Question 42

Give an example: Plantar flextion

Answer 42

pointing toes to the ground

Question 43

Give an example: Inversion

Answer 43

Turn the inner foot in towards the body

Question 44

Give an example: Eversion

Answer 44

Turn the outer foot away from the middle of the body

Question 45

Give an example: Supination

Answer 45

Forearm rotates laterally with palms facing upwards

Question 46

Give an example: Pronation

Answer 46

Forearm rotates medially with palms facing posteriorly

Question 47

Give an example: Opposition

Answer 47

Allows the thumb to move and tough fingers on the same hand

Question 48

Define: Primary Mover

Answer 48

Muscle that has the major responsibility of causing a particular movement

Question 49

Define: Antagonist

Answer 49

Muscles that oppose or reverse the movement

Question 50

Define: Synergists

Answer 50

Helps prime movers by producing the same movement by reducing undesirable movements

Question 51

Define: Fixators

Answer 51

The hold the bone still or stabilise the origin of a prime mover- so all tension can be used to move the insertion bone

Question 52

Name the 3 Muscle types

Answer 52

Skeletal
Cardiac
Smooth