Muscles Flashcards Preview

Anatomy > Muscles > Flashcards

Flashcards in Muscles Deck (110)
Loading flashcards...
0
Q

Special characteristics of muscle tissue

A
  1. excitability
  2. Contractility
  3. Extensibility
  4. Elasticity
1
Q

4 functions of muscle

A
  1. Produces movement
  2. Maintains posture
  3. Stabilizes Joints
  4. Generates heat
2
Q

Excitability

A

Also called responsiveness, ability to receive and respond to stimulus

3
Q

Contractility

A

Ability to shorten forcibly, sets muscle apart from other tissue types

4
Q

Extensibility

A

Ability to extend or stretch

5
Q

Elasticity

A

Ability of muscle cell to recoil and resume it’s resting length after stretching

6
Q

3 types of muscle tissues and there similarities and differences

A
  1. Skeletal muscle: cells called muscle fibers, have striations, voluntary
  2. Cardiac muscle: striated, involuntary
  3. Smooth muscle: no striations, visceral, involuntary
7
Q

Name of the plasma membrane of a muscle cell

A

Sarcolemma (muscle husk)

8
Q

Muscle cell cytoplasm

A

Sarcoplasm

9
Q

Connective tissue sheaths of a muscle

A
  1. Epimysium
  2. Perimysium and fascicles
  3. Endomysium
10
Q

Epimysium

A

Overcoat of DICT surrounding the whole muscle

11
Q

Perimysium

A

Surrounds each fascicle, made of fibrous connective tissue

12
Q

Endomysium

A

CT that surrounds each muscle fiber

13
Q

Parts of a muscle

A
  1. epimysium
  2. Perimysium
  3. Endomysium
  4. Tendons
  5. Fascicles
  6. Nerves and blood vessels in the muscle
14
Q

When a muscle contracts, the movable bone

A

The insertion moves towards the orgin

15
Q

Insertion

A

Movable part of the muscle

16
Q

Origin

A

Less movable part of the muscle

17
Q

Direct attachment

A

(Fleshy attachment) the epimysium of the muscle is fused with a periosteum or perichondrium

18
Q

Indirect attachment

A

Extends bruin muscle as a tendon or aponeurosis

19
Q

Aponeurosis

A

Sheet like ct that connects muscles to a bone, cartilage or other muscles

20
Q

Why are muscle fibers multinucleate?

A

The muscle cells fuse together

21
Q

Myofibrils

A

Individual fiber in the muscle cell made up of sarcomeres

22
Q

A bands

A

A dark band on a myofibril

23
Q

I band

A

Light band on a myofibril

24
Q

Saracomere

A

The smallest contractile unit of a muscle, myofibril a are made up of sarcomeres. A sarcomere is a section of a myofibril

25
Q

Organizational and structure level of a muscle from organ to molecular structure

A
  1. Muscle
  2. Fascicle
  3. Muscle Fiber (cell)
  4. Myofibril
  5. Sarcomere
  6. Myofilament
26
Q

Myofibril

A

Organelle of the muscle fiber made up of sarcomeres which contract; an organelle

27
Q

Types of filaments in a sarcomere

A
  1. Myosin (thick filaments)
  2. Actin (thin filaments)
  3. Titin (elastic filaments)
28
Q

Sarcolemma

A

Plasma membrane of a muscle fiber

29
Q

Sarcoplasm

A

Cytoplasm of a muscle cell

30
Q

Difference between fibers, myofibrils, and filaments

A

Fibers= cells, myofibrils= organelle, filaments= extended macromolecular structure

31
Q

Z disc

A

Boundary of each sarcomere

32
Q

A band

A

Width of myosin

33
Q

I band

A

Area with NO myosin, overlaps 2 neighboring sarcomeres

34
Q

H zone

A

Middle of the band that doesn’t have actin

35
Q

M line

A

Very center of the myosin

36
Q

Titin

A

Helps muscle cell to spring back to shape after stretching. Stiffens as it uncoils to prevent the sarcomeres from being pulled apart

37
Q

Two sets of intracellular tubules

A

Sarcoplasmic reticulum and T tubules

38
Q

Sarcoplasmic reticulum

A

Modified smooth endoplasmic reticulum that stores calcium ions and releases them on demand when the muscle fiber is stimulated to contract

39
Q

Muscle contraction

A
  1. Nerve impulse travels down neuron
  2. Axon terminal releases a neurotransmitter
  3. NT diffuses through synaptic cleft (little gap) and binds to sarcolemma
  4. Sarcoplasmic reticulum releases calcium ions which causes the myosin heads to to bind to the actin, ATP is then used to bend the myosin heads inwards
  • these two things cause actin to get pulled towards the center of the sarcomere
  • A band has not changed
  • I band shrinks to the size of Z disc
  • Hzone disappears
40
Q

Sliding filament mechanism/ theory

A

Myosin and actin do not get shorter, they are just sliding over each other. Shortening the sarcomere

41
Q

Muscle extension

A

Muscles do not forcibly lengthen. Gravity can pull a muscle back to its original length
- contracting a muscle on the opposite side of a joint can pull a muscle back to its original length

42
Q

Motor unit

A

A neuron and all the muscle fibers that it innervates

  • a muscle produces more or less force by using more or fewer motor units
  • an individual motor unit can be very large (lots of muscle fibers per neuron) or very small (vice versa) nuance movements of facial muscles
43
Q

Large motor units

A

Produce big movement and lots of force

44
Q

Small motor units

A

Produce small, subtle movement/ little force

45
Q

Muscular dystrophy

A

A group of inherited muscle destroying diseases that generally appear during childhood. The muscle cells enlarge initially then atrophy and disintegrate. Most common form is Duchenne muscular distrophy common in males

46
Q

Duchenne muscular distrophy

A

A type of MD caused by a recessive gene in mostly male children which produces a defective cytoplasmic protein (dystrophin). Starts at 2-7 in healthy children, disease progresses from extremities upward to face, chest and heart muscles.Victims rarely live beyond 20s dying of respiratory failure

47
Q

Fibromytosis

A

Fibromyalgia, a group of of conditions involving chronic inflammation of a muscle it’s connective tissue coverings and tendons and capsules of nearby joints. Symptoms: tenderness, fatigue and frequent awakening from sleep

48
Q

Hernia

A

Protrusion of an organ through its body cavity wall. Can be congenital or caused by heavy lifting, obesity and muscle weakening

49
Q

Myalgia

A

Muscle pain

50
Q

Myofascial pain syndrome

A

Pain caused by tightened band of muscle fibers, which twitch when the skin over them is touched. Overused or strained postural muscles

51
Q

Myopathy

A

Any disease of the muscle

52
Q

Myotonic dystrophy

A

Less common form of MD. Not sex specific. Gradual reduction in muscle mass and control if muscles.abnormal heart rhythm and diabetes. Worse in subsequent generations because gene repeats more

53
Q

RICE

A

Rest, ice, compression and elevation. Standard treatment for a pulled muscle or extensively at reached tendons and ligaments

54
Q

Strain

A

Commonly called a pulled muscle.excessive stretching of the muscle causes it to tear. Due to over use and abuse. Injured muscle becomes inflamed adjacent joints are immobilized

55
Q

Spasm

A

A sudden involuntary twitch in smooth or skeletal muscle ranging from merely irritating to very painful. Facial an eyelid spasms are called tics and could possibly indicate a psychological factor. A cramp is a prolonged spasm

56
Q

Tetanus

A

A state of sustained contraction of a muscle that is a normal aspect of skeletal muscle functioning. A disease cause by a bacteria resulting in painful spasms of certain skeletal muscles, which then turns into fixed rigidity of the jaw (lockjaw) and spasms of the trunk and limb muscles. Fatal due to respiratory failure

57
Q

What happens when a muscle shortens

A

The insertion (attachment to the movable bone) moves towards its origin (fixed immovable point of attachment)

58
Q

4 functional groups of muscles

A
  1. Prime movers
  2. Antagonists
  3. Synergists
  4. Fixators
59
Q

Prime mover

A

Or agonist(leader) has responsibility for producing a specific movement ex. Pectoralis major a prime mover of arm flexion

60
Q

Antagonist

A

(Against the leader) serves to stretch or remain relaxed. Helps to regulate action of prime mover by providing resistance and helps to not overshoot the mark and helps to slow down or stop a movement
Ex. Latissimus dorsi

61
Q

Prime movers and antagonists are located

A

On opposite sides of the joint across which they act on

62
Q

Synergist

A

Help prime movers

63
Q

Synergists help prime movers in what 2 ways?

A
  1. Adding a little extra force to the same movement

2. Reducing undesirable or unnecessary movements that might occur as the prime mover contracts

64
Q

Fixators

A

When a Synergist immobilized a bone or a muscle’s origin so that the prime mover has a stable base on which to act, they are called fixators

65
Q

A muscle may

A

Serve as a antagonist or Synergist or prime mover in different movements

66
Q

Types of fascicle arrangement (muscle pattern)

A
  1. Parallel
  2. Convergent
  3. Pennate
  4. Circular
67
Q

Parallel fascicle arrangement:

A

Strap like or fusiform. Ex. Sartorius (strap like) biceps brachii (fusiform)

68
Q

Fusiform

A

Wider in the middle and tapered at the ends

69
Q

Convergent fascicle arrangement:

A

Fascicles come together at insertion ex. Pectoralis major

70
Q

Pennate fascicle arrangement

A

“Feather-like”

71
Q

3 forms of pennate muscles

A
  1. Unipennate; extensor digitorum long us
  2. Bipennate; rectus femorus
  3. Multipennate; deltoid
72
Q

Circular fascicle arrangement

A

When fascicles are arranged in concentric rings. Surround external body openings. Sphincters (squeezers) ex. Orbicularis muscles

73
Q

Skeletal muscles are named by what 7 ways

A
  1. Location
  2. Shape
  3. Relative size; Maximus, minimums, longus, brevis
  4. Direction/arrangement of fascicles; rectus(straight), transverse, oblique(angle)
  5. Location and attachments (origin and insertion)
  6. The number or orgins (-ceps, biceps, triceps, ect.)
  7. Action
74
Q

Charley horse

A

A muscle contusion. Tearing of the muscle followed by hematoma and pain

75
Q

Electromyography

A

A recording and interpretation of graphic records of the electrical activity of contracting muscles. Best way of determining functions of muscles and muscle groups

76
Q

Hernia

A

Abnormal protrusion of abdominal contents. Goes through weak spot in muscle

77
Q

Quadriceps and hamstring strain

A

Also called pulls. Tearing these muscles at the tendons. Common athletes who do not warm up properly and fully extend their hip or knee quickly or forcefully

78
Q

Ruptured calcaneal tendon

A

Common injury to Achilles’ tendon. Happens mostly in older people or young sprinters. Exaggerate dorseflexion and plantar flexion almost impossible. Calf bulges. Repaired surgically.

79
Q

Shin splints

A

Pain in the anterior compartment of the leg, caused by irritation of the tibialis anterior muscle. Follows extreme or unusual exercise without adequate prior conditioning

80
Q

Tennis elbow

A

Tenderness due to trauma or overuse of the tendon of origin of the fore arm extensor muscles at the lateral Epicondyle of the humerus

81
Q

Torticollis

A

(Tort= twisted) a twisting of the neck in which there is chronic rotation and tiltin of the head to one side. Due to injury of the sternocleidomastoid on one side; also called wryneck

82
Q

Overall Function of the nervous system

A

The master controlling and communicating system of the body

83
Q

3 functions of the nervous system

A
  1. Sensory input
  2. Integration
  3. Motor output
84
Q

Sensory input

A

Receptor monitor change inside and outside the body.

85
Q

Integration

A

Processing and interpreting sensory input, making decisions; dictates the response

86
Q

Motor output

A

Response (control muscle, glands, etc)

87
Q

Divisions if the nervous system

A
  1. Central Nervous system

2. Peripheral nervous system

88
Q

Central nervous system

A
  • consists of brain and spinal chord

- performs integration

89
Q

Peripheral nervous system

A
  • consists of nerves, ganglia, receptors etc

- involved in sensory and motor

90
Q

Afferent

A

(Sensory)

Involves somatic sensory and visceral sensory

91
Q

Efferent

A

(motor) somatic motor and visceral motor

92
Q

Autonomic nervous system

A

Consists of visceral motor nerve fibers that regulate the activity of smooth muscles, cardiac muscles and glands; involuntary nervous system

93
Q

Somatic nervous system

A

Composed of somatic motor nerve fibers that conduct impulses from CNS to skeletal muscles; voluntary nervous system

94
Q

Somatic sensory fibers

A

Fibers convey impulses from the skin, skeletal muscles and joints (soma= body)

95
Q

Visceral sensory fibers

A

Transmit impulses from guts within ventral body cavity

96
Q

Neurons

A

Nervous system cells that transmit electrical signals

97
Q

Neuroglia

A

Support and protect neurons

98
Q

Special characteristics of neurons

A
  • conduct electrical impulses down the length of a cell
  • longevity: can live and function for entire life time
  • do not divide: can not be replaced
  • high metabolic rate: uses a lot of o2 and glucose
99
Q

Parts of a neuron

A
  1. Cell body; contains organelles
  2. Chromataphilic bodies; rough ER
  3. Dendrites; numerous and branched, receptor sites
  4. Axon; only one, has terminal branches at its end, generates and conducts impulses, releases neurotransmitters
100
Q

What do dendrites, the cell body and axons do?

A

Dendrites and cell body receive info and and axons send info

101
Q

How are neurons classified?

A
  1. Structure

2. Function

102
Q

Functional classification of a neuron

A
  1. Sensory neurons (afferent)
  2. Interneurons
  3. Motor neurons (efferent)
103
Q

Sensory (afferent) neurons

A

Send messages toward CNS; located in PNS

104
Q

Interneurons

A

Involved in integration; found in CNS

105
Q

Motor (efferent) neurons

A

Send messages away from CNS; located in PNS

106
Q

Structural classification of neurons (# of processes)

A
  1. Multipolar
  2. Bipolar
  3. Unipolar
107
Q

Multipolar neurons

A

Have many dendrites and one axon; can be motor or Interneurons

108
Q

Bipolar neurons

A

One dendrite, one axon only found in special sense organs

109
Q

Unipolar neurons

A

One axon typically sensory neurons