Muscular System Part 2 Flashcards
1
Q
calat-
A
something inserted
2
Q
erg-
A
work
3
Q
hyper-
A
over, more
4
Q
inter-
A
between
5
Q
laten-
A
hidden
6
Q
myo-
A
muscle
7
Q
sacro-
A
flesh
8
Q
syn-
A
together
9
Q
tetan-
A
stiff
10
Q
-troph
A
well fed
11
Q
how many muscles in the human body
A
approximately 600 (640)
12
Q
2 main components of muscle
A
75% water, 20% protein
13
Q
Are skeletal muscles a push or a pull, why?
A
pull, the muscle fibers shorter, pull the insertion toward the origin
14
Q
what percent of body weight is muscle
A
40-50%
15
Q
4 main functions of muscles
A
move food and body fluids (urine and blood), production of heat, provide muscle tone and movement of skeleton, generate heartbeat
16
Q
three muscle types
A
skeletal, smooth, cardiac
17
Q
in what 3 ways do the types of muscles differ
A
structure, location, function
18
Q
is smooth muscle voluntary or involuntary
A
involuntary
19
Q
what kind of muscle does this describe - elongated spindle but not the longest, one nucleus near the center of the cell, no striations
A
smooth muscle
20
Q
describe the contractions of smooth muscles
A
slow and prolonged
21
Q
2 major types of smooth muscle
A
Multi-unit and Visceral
22
Q
describe Multi-unit smooth muscle and give examples
A
not well organized, appears as fibers instead of sheets (iris and blood vessels)
23
Q
where is the visceral smooth muscle in comparison to the multi-unit smooth muscle
A
deeper, towards the interior
24
Q
Describe structure, function, and location of visceral smooth muscle
A
in sheet layers, causes rhythmic wavelike contraction (peristalsis), found in walls of hollow organs (stomach, intestines, bladder, uterus)
25
This muscle type is only found in the heart
cardiac muscle
26
is cardiac muscle voluntary or involuntary?
involuntary
27
describe the structure of cardiac muscle
uni-nuclear, cells form a branching interlacing network, some striations, sarcoplasmic reticulum poorly developed, many mitochondria, slow contractions
28
the striated and voluntary muscle
skeletal
29
components of skeletal muscles
cells up to 30 cm long and 1mm wide, multinucleated, muscular, nervous, vascular, and connective tissues
30
immovable end of a muscle
origin
31
moveable end of a muscle
insertion
32
In muscles such as the pectoralis major, what changes when the function changes?
origin and insertion
33
muscle doing most of the work in a muscle group
prime mover
34
muscle that aids the prime mover
synergist
35
muscles that move in the opposite direction of the prime mover
antagonist
36
4 general breakdowns of a muscle
muscle to fiber bundle to muscle cell to myofibril
37
material that separates individual skeletal muscles from adjacent muscles and forms cord like tendons
fascia
38
thing that surrounds the muscle
epimysium
39
this extends inward from the epimysium to separate the muscle tissue into smaller compartments
perimysium
40
this surrounds the groups of muscle fibers within the fascicle
endomysium
41
what is stimulated during muscle contraction
motor neuron
42
what is the enlargement at the end of a muscle fiber
motor end plate
43
the union between a nerve fiber and a muscle fiber
neuromuscular junction
44
this is secreted by an end plate that diffuses to myofibrils and causes contraction
neurotransmitter substance
45
what is made up of the motor neuron and muscle fibers
motor unit
46
small motor unit vs large motor unit
smaller the motor unit the less muscle fibers and the finer the movement
47
What neurotransmitter is responsible for muscle contraction?
acetylcholine
48
What does acetylcholine bind to after it passes through the gap?
muscle fiber membrane receptors
49
What is released from the sarcoplasmic reticulum into the sarcoplasm?
Ca ions
50
What do the Ca ions bond to?
Troponin units on actin fibers
51
What is exposed by the displacement of tropomyosin along the myofilaments?
binding sites
52
What catalyzes ATP?
ATPase
53
What two components allow contraction to continue?
ATP and Ca ions
54
What breaks down acetylcholine?
acetylcholinesterase
55
Where do Ca ions go after muscle contraction ends
sarcoplasmic reticulum
56
Disorder characterized by missing or abnormal dystrophin or the glycoproteins.
Muscular dystrophy
57
Disorder in which dystrophin is missing, symptoms being by age 5, present in boys only, cannot walk by 13, dies in early adulthood
Duchenne Muscular Dystrophy
58
A slowly progressing weakness in the muscles of the hands and feet and decreases in tendon reflexes - caused by an extra gene
Charcot - Marie - Tooth Disease
59
A rare and inherited form of heart failure, begins in 40s, lethal 50% of the time within 5 years - caused by tiny genetic error
Hereditary Idiopathic Dilated Cardiomyopathy
60
Group of disorders that affects a person's ability to move and maintain balance and posture
cerebral palsy
61
chronic autoimmune disorder in which antibodies destroy the communication between nerves and muscle, resulting in weakness of the skeletal muscles
Myasthenia Gravis
62
A chronic disorder that causes pain and tenderness throughout the body, as well as fatigue and trouble sleeping
Fibromyalgia
63
A disorder that affects muscles used for movements (skeletal muscles) begins in early childhood - prevents muscles from relaxing
Myotonia congenita
64
What reacts to generate the force of contraction
actin and myosin filaments
65
The cross-bridges of _________ form linkages with _______
Myosin filaments, actin filaments
66
What supplies energy for muscle fiber contraction
ATP
67
Describe the role of Creatine Phosphate
stores energy that can be used to synthesise ATP
68
For a while, which is faster, the ATP supply from the mitochondria or the oxygen supply from blood
ATP from mitochondria
69
This stores O2 and gives muscles their reddish/brown appearance
myoglobin
70
Muscles respire _________ during rest or moderate exercise when they receive enough oxygen
aerobically
71
What accumulates during strenuous exercise as a result of oxygen deficiency
lactic acid
72
__________ is the amount of oxygen required to convert accumulated lactic acid to glucose and restore the supplies of ATP and Creatine Phosphate
Oxygen Debt
73
a ________ muscle loses its ability to contract
fatigued
74
The accumulation of lactic acid leads to _________ and lowers ____
muscle fatigue, PH
75
3 possible causes of muscle fatigue
lactic acid accumulation, interruption of blood supply, exhaustion of acetylcholine
76
common name for sustained involuntary contraction
cramp
77
How much of the energy released in cellular respiration is lost as heat?
more than half
78
________ is an important source of body heat
muscle action
79
The minimal stimulus required to elicit a muscular contraction
threshold stimulus
80
Describe the all-or-none response
if a skeletal muscle fiber contracts at all, it will contract completely, motor units respond this way
81
__________ is the recording of an electrically stimulated isolated muscle
myogram
82
common name for a single, short contraction reflecting the stimulation of some motor units in a muscle
twitch
83
the time between stimulus and responding muscle contraction
latent period
84
what follows the latent period
a period of contraction and then relaxation
85
a rapid series of stimuli may produce _______ of twitches
summation
86
Forceful sustained contraction without relaxation
tetanic contraction (tetanus)
87
small numbers of motor units will contract at a _______
low intensity of stimulation
88
At __________ of stimulation, other motor units are recruited until the muscle contracts with _____.
increasing intensities, maximal tension
89
________ and ________ together can produce a sustained contraction of increasing strength
summation and recruitment
90
Describe muscle tone
even when a muscle is at rest, its fibers usually remain partially contracted
91
enlargement of a muscle due to enlargement of muscle fibers rather than increase in number of fibers
muscular hypertrophy
92
What does muscular hypertrophy allow for and why
it allows more forceful contractions because strength is related to the diameter of muscle fibers.
93
muscle size decreases because of disuse
atrophy
