Muscles Flashcards
(257 cards)
1
Q
Muscle weakness happens when?
A
in disease
2
Q
shivering produces what?
A
heat to raise core body temperature
3
Q
What muscle shivers to produce heat?
A
skeletal muscle
4
Q
What muscle helps with locomotion?
A
skeletal muscle
5
Q
What muscle helps with peristalsis?
A
smooth muscle
6
Q
What muscle contributes in how a dog raises its “hackles”?
A
smooth muscle
7
Q
In what muscle is an injection placed?
A
skeletal muscle
8
Q
What 3 muscle types are there?
A
smooth, cardiac, and skeletal
9
Q
What is smooth muscle?
A
muscle that is involuntary unstriated
10
Q
What is cardiac muscle?
A
muscle that is involuntary striated
11
Q
What is skeletal muscle?
A
muscle that i voluntary striated
12
Q
smooth muscle has
A
no striations
13
Q
contraction is what within the smooth muscle?
A
inherent
14
Q
smooth muscle is generally under what control?
A
autonomic
15
Q
What is autonomic?
A
happens without thinking about it
16
Q
how is smooth muscle shaped?
A
spindle-shaped, nucleus centrally located
17
Q
Where is smooth muscle located?
A
wall of GI, urogenital system, blood vessel walls, respiratory tract, eye, raises hairs when cold or frightened
18
Q
Cardiac muscle is what?
A
striated
19
Q
contraction within the cardiac muscle is what?
A
inherent
20
Q
What control is cardiac muscle under?
A
autonomic control
21
Q
What is cardiac muscle shaped like?
A
star-shaped, has projections, nucleus centrally located`
22
Q
Where is cardiac muscle located?
A
heart muscle
23
Q
Skeletal muscle is what?
A
striated
24
Q
What control is skeletal muscle under?
A
conscious control of contraction
25
What does the skeletal muscle look like?
separate, distinct muscles in many shapes
26
What kind of nucleus does skeletal muscle have?
multinucleated
27
Where is skeletal muscle located?
the "flesh" of animals
28
What does the connective tissue do for muscle cells?
surrounds and supports each muscle cell, bundle of muscle cells and groups of bundle that form the muscle
29
Connective tissue directs the pulls of what because of the harness formed by the connective tissue parts surrounding all of it?
muscle
30
Connective tissue provides a path for what?
blood vessels and nerves to enter and exit the muscle
31
which muscle cells intertwine to form a network of "anastomosing" cells?
cardiac muscle
32
The anastomosing cells from the what?
harness
33
Intercalated disks connect what to what to permit electrical transmission?
cell to cell
34
What readily spreads from cell to cell in cardiac muscle?
action potentials
35
Cardiac muscle works as a what?
single mass, "syncytium"
36
What is marbling?
fat found between muscle tissue bundles
37
Amount of connective tissue present in muscle combined with amount of fat present determines what?
relative toughness vs. tenderness of meat
38
What 3 different shapes can skeletal muscle have?
parallel, spindle shaped, penniform
39
What is parallel?
wide sheets and narrow bands
40
What is spindle-shaped?
fat center
41
What is penniform?
fan shaped and has the greatest power
42
Where is parallel found?
abdominal muscles have a wide sheet and inner thigh muscle has narrow bands
43
Where is spindle-shaped found?
biceps and triceps mm
44
Where is penniform found?
trapezius mm
45
How does muscle attach to bone?
tendons
46
Most tendons are what?
cords or bands
47
Some tendons are what?
flat sheets
48
aponeuroses
tendons that are flat sheets
49
Some tendons are so tiny that the muscle appears to do what?
attach directly to the bone
50
What two types of muscle do not attach to 2 different bones?
cutaneous trunk and sphincter muscles
51
What is the cutaneous trunci?
attachment between skin and c.t. over muscles
52
Wha does the cutaneous trunci allow the skin to do?
"flick" to remove a fly
53
What are sphincter muscles?
striated or smooth
54
Where are sphincter muscles located?
surrounding an opening
55
Flexors do what?
flex the joint
56
Extensors do what?
extend the joint
57
Adductors do what?
adduct the limb or bring it closer
58
Abductors do what?
abduct the limb or move it away
59
Synergists do what?
stabilize one or more bones
60
Why would a muscle groups be unacceptable for injection purposes?
damage to cuts of meat, no good place for an infection to easily drain without causing extensive tissue damage
61
What are some acceptable injection sites for the ham area of the rear thigh?
Quadriceps femoris, biceps femoris, semitendinosus, semimembranosus
62
In what animals should injections be placed in the ham area of the rear thigh?
small animals, could be used in horse if needed to rotate injection sites during long treatment
63
What are some acceptable injection sites for the arm area of the front leg?
triceps
64
In what animals could an injection be given in the arm area of the front leg?
horse and small animals if needed to rotate shots during a long treatment
65
Where is an acceptable injection site in the chest?
pectorals
66
Where is an acceptable injection site in the back?
lumbar muscles
67
what injections may the lumbar muscles be used for?
deep IM injections
68
What is an acceptable injection site in the neck?
brachiocephalicus, omotransversarius, trapezius, serratus ventralis
69
In what animals is the preferred injection site in the neck?
cattle
70
one muscle fiber= once muscle cell= what?
one "myofiber"
71
Within the muscle cell there are how many myofibrils?
hundreds to thousands
72
within the myofibril are how many myofilaments?
4500
73
some fibers are built for what and others are built for what?
endurance and quick action
74
Quarter horse have more what?
quick fibers
75
Arabian has more what?
endurance fibers
76
What are the contractile elements?
actin and myosin
77
"cross bridges" on the myosin link with what during contraction and pull it toward the center of the muscle cell
actin
78
The movement of actin along the myosin causes the striped pattern of what muscle?
skeletal
79
a piece of muscle placed under the microscope will have visible stripes due to what?
overlap of actin and myosin
80
What is the role of the sarcotubular system?
rapid transit for muscle messages
81
What is the sarcotubular system?
a network of tubes
82
what does the sarcotubular system surround?
each myofibril
83
What does the sarcotubular system form?
a connecting system that allows rapid conduction of nerve impulses to all parts of the muscle fiber at one time
84
What does the sarcotubular system provide?
for more synchronized contraction
85
In the sarcotubular system, the entire muscle fiber is depolarized simultaneously and soon does what?
contracts all together
86
How does nerve information get to the muscle cell?
through the motor unit
87
What is a motor unit?
the nerve fiber plus all the muscle fibers innervated
88
A muscle fiber is also a what?
muscle cell
89
one nerve will branch to what?
many muscle cells
90
What is the neuromuscular junction?
the point where the nerve reaches the muscle fiber
91
What separates the nerve ending and the muscle in the neuromuscular junction?
a space
92
In the neuromuscular junction when nerve is stimulated, the information travels along what to the end of the nerve?
never fiber
93
acetylcholine stored at the end of the nerve and is released into what?
the neuromuscular junction
94
What is Acetylcholine?
transmitter substance or a neurotransmitter
95
Ach binds with what on the muscle fiber surface?
receptor sites
96
Ach increases what of the muscle fiber membrane to sodium?
permeability
97
Ach what kind of drug?
the "classic cholinergic agonist" drug
98
Ach should not be used how?
clinically
99
Ach stimulates what?
cholinergic sites
100
Depolarization moves how?
in all directions from the neuromuscular junction
101
Depolarization spreads how?
rapidly to the entire muscle through the sarcotubular system
102
The sarcotubular system releases what into the area around the actin and myosin contractile elements
calcium
103
Calcium helps what to form?
cross-bridges
104
not every nerve signal does what?
triggers a noticeable muscle contraction
105
individual muscles may contract but not what?
the entire muscle
106
If the change in cell charge is not enough to trigger a change all along the cell what happens?
depolarization will not occur beyond the area of the receptor site and the entire muscle cell will not contract
107
if the threshold is met fiber contracts to it maximum for the conditions at the time of stimulation.. fatigue will result in less contraction. Threshold not met then no contraction is an example of what?
the all or none rule
108
small contractions maintain the what of the muscle?
tone
109
small contractions makes the difference between a firm, healthy muscle at rest at rest and the soft, flabby unused muscle resulting from what?
nerve paralysis
110
A contraction will not be seen unless what?
the stimulus is enough to trigger many muscle fibers to contract
111
What is the #1 important role of calcium?
accelerates ACh release from the end of the nerve
112
What is the #2 important role of calcium?
initiated the contraction process at the level of the myofilaments
113
What is the #3 important role of calcium?
initiates muscle relaxation when the calcium returns from the myofilaments to the sarcotubular system
114
What is the #4 important role of calcium?
contributes to ATP release
115
When Ca+ is low there is a what ACh release from the nerve ending
decreased
116
The decreased ACh may not be enough to cause what of the entire muscle cell membrane and production of an impulse in the muscle
depolarization
117
Decreased calcium levels may not be enough to do what?
form cross-bridges and cause myofilament shortening
118
What is the result of accelerating ACh release from the end of the nerve?
no muscle contraction will occur
119
What is the result of initiating the contraction process at the level of the myofilaments?
no contraction will occur
120
Low calcium in situations such as hypocalcemia, parturient paresis, milk fever, and eclampsia cause what?
muscle weakness
121
In cows low calcium is one of many causes of what?
downer cow syndrome
122
What is downer cow syndrome?
the cow is down and can't get up
123
At the end of contraction, calcium is pumped out of the area of the myofilaments and back where?
to the sarcotubular system
124
When calcium leaves, what occurs?
muscle relaxation
125
Low ATP can cause muscles to fail to do what?
relax
126
When calcium levels are low, not enough what is produced?
ATP
127
There will not be enough energy to move Ca+ away from the myofilaments and back into where?
sarcotubular system
128
What is ATP?
the process of muscle contraction requires energy
129
ATP is the immediate source of what?
energy
130
ATP changes to what to be used again?
ADP+ Creatine phosphate
131
Creatine phosphate is in what in the muscle?
high concentration
132
what is required for contraction?
ATP and Calcium
133
What is required for relaxation and return of Ca+ to sarcotubular system?
ATP
134
How much ATP is needed for muscle contraction?
low amounts
135
How much ATP is needed for muscle relaxation?
high amounts
136
With low ATP levels a muscle may be able to do what?
contract but not relax
137
Acetylcholinesterase inactivates ACh very soon after what?
impulse for muscle contraction occurs contractions are quick
138
With acetylcholinesterase, effects of ACh at the neuromuscular junction are what?
prolonged
139
Desirable in some disease state where too much of what stops the action of ACh too soon
acetylcholinesterase
140
Anti cholinesterase interferes with what and allows ACh to build up and act longer?
acetylcholinsterase
141
What is used to treat rumen atony?
physostigmine and neostigmine
142
How does physostigmine and neostigmine work to treat rumen atony?
increases gastric emptying, stimulates peristalsis, empties the bladder of large animals, aid in Dx of myasthenia gravis
143
Too much anti cholinesterase is what?
toxic
144
too much anti cholinesterase causes what?
prolonged ACh effect
145
Muscle spasms and asphyxiation due to spasms of skeletal muscle is necessary for what?
respiration
146
How else is anti cholinesterase used?
nerve gas in WWII and Insecticides
147
What are some organophosphates used in insecticides?
malathion, parathion, and diazinon
148
How are insecticides applied?
external and orally
149
When are insecticides dangerous to animals and humans applying them?
if directions are not followed accurately
150
What is a symptom of toxicity?
drooling
151
What is very important to body function?
heat
152
heat is very important to maintain normal body temperatures essential for normal what to occur?
body chemical reactions
153
A reduction in what will result in a slowing of metabolism with potentially bad results
body temperature
154
body cooling may result in what?
shivering
155
shivering is the body's attempt to do what?
generate heat by muscle contraction
156
When a newborn calf is cold and weak what might it need?
animal needs to be warmed up before it is fed or the food will not digest
157
When a newborn calf is cold and weak what might it be?
dehydrated, this will cause poor blood flow to the digestive system
158
When a newborn calf is cold and weak what should be done?
warm it up and replace fluids, then feed it
159
What do reptiles depend on for their body temperature?
environmental temperature
160
Without a heat source in a reptiles cage, a pet reptile will get so cold it cannot do what?
digest food
161
Placing a heat source in a reptiles cage allows what?
warm and cool areas
162
Why is it important to have a warm area in a reptiles cage?
it has somewhere to go to digest food
163
Surgery is a prime place for what to occur in a veterinary practice?
heat loss
164
water circulating blankets, warm air blankets, warm IV fluids, socks, plastic wrap, bottles filled with hot water, rice bags, baer huggers are ways to do what?
avoid heat loss during surgery
165
What is summation?
an addictive effect of contraction
166
what is the 1st way a summation can occur?
the more motor units stimulated to contract at the same time, the stronger the contraction
167
What is the 2nd way a summation can occur?
increased frequency of contraction rate allows subsequent contractions to merge into a single stronger contraction
168
Under normal circumstances which way of summation occurs?
both of them
169
What is tetany?
continuous contraction (or muscle spasm)
170
How does tetany happen?
stimulus to contract has been so rapid that continuous contraction is the result
171
What causes tetany?
many disease conditions
172
What is warming up?
improved muscle contraction strength by slowly increasing use when first beginning to use muscles
173
What is needed before maximum efficiency is reached for warming up?
30 contractions
174
What is fatigue?
decreased force of contraction
175
what is fatigue due to?
decrease in energy supply and calcium to the myofilaments actin and myosin
176
muscle contraction itself comprises what decreasing blood flow to muscle and adding to conditions supporting muscle fatigue?
blood vessels
177
What is rigor?
extreme fatigue
178
Decreased blood flow to muscle produces what?
ischemia, lack of blood supply in and lack of blood flow out
179
what is ischemia?
lack of blood
180
What happens during rigor to ATP?
depletes it
181
What does not occur during rigor?
muscle relaxation
182
What is rigor mortis?
rigor occurring after death
183
With muscle decomposition what is released from the sarcotubular system?
calcium
184
Calcium causes what to lock together and form cross-bridges as in life- muscles contract
myofilaments
185
without what, muscle contraction continues until cell autolysis and protein degradation break down the muscle
ATP
186
What is tone?
slight tension exhibited by all muscles at rest
187
What happens during tone?
continuous nerve transmission to muscle keeps the muscle ready to contract if stimulated
188
Tone varies with what?
mental state
189
when you are anxious what happens to tone?
intensified muscle tone
190
When you are asleep what happens to tone?
low muscle tone allows relaxation
191
What is atrophy?
decrease in size
192
What is atrophy due to?
disuse and denervation
193
what is hypertrophy?
increase in size of individual cells
194
all increases in size of muscle at any stage in life following bitch are due to hypertrophy of individual muscle fibers happens during what?
hypertrophy
195
When is hypertrophy normal?
during weight lifting
196
when is hypertrophy abnormal?
high mountain disease of cattle
197
what is high mountain disease?
pulmonary hypertensive heart disease or brisket disease
198
what animals are uniquely susceptible to high mountain disease?
cattle
199
when are cattle susceptible to high mountain disease?
when living above 6,500 ft
200
what animals having strong responses to high mountain disease?
cattle, horses, pigs
201
what animals are weak responders to high mountain disease?
humans, dogs, guinea pigs, llamas
202
What is pulmonary hypertensive heart disease?
response to chronic hypoxia, hypocapnia, respiratory alkalosis of high -altitude environment
203
response to chronic hypoxia, hypocapnia, respiratory alkalosis of high -altitude environment, these changes collectively result in what?
pulmonary vasoconstriction, pulmonary hypertension and ultimately lead to congestive heart failure
204
what is hyperplasia?
increase in size due to increase in # of cells
205
in smooth muscle myofilaments actin and myosin are present but not what?
aligned
206
in smooth muscle innervation is what?
dual usually
207
what cause simultaneous smooth muscle stimulation and inhibition?
parasympathetic and sympathetic
208
in smooth muscle fraction of cells are supplied with what?
nerves
209
pacemaker cell points can initiate what of smooth muscle?
depolarization and contraction
210
what is not needed for smooth muscle to contract?
nerve stimulation
211
smooth muscle is sensitive to what all over through pacemaker cells?
stimuli
212
in smooth muscle, stimuli as what causes contraction?
distention, chemical, hormonal, and self excitation
213
in smooth muscle what is poorly developed?
sarcotubular system
214
what is the result in smooth muscle when the sarcotubular systems are poorly developed?
slower response time and longer duration of contraction
215
in smooth muscle the result is harder to what?
fatigue or tetanize smooth muscle
216
in smooth muscle the result in contractions are often what?
rhythmic
217
in smooth muscle the result has what kind of stretching possible without a contraction resulting?
gradual
218
gradual stretching in the smooth muscle allows stomach, bladder, food, and uterus to do what?
stomach and bladder to fill, food to pass down intestine, and uterus to stretch during gestation
219
what often causes contraction in smooth muscle?
sudden stretch
220
what characteristics of smooth muscle allow what features as well>
constant pressure with little cell energy
| allows constant degree of contraction for normal function
221
with calcium and smooth muscle what is linked to calcium as it is in skeletal muscle?
contraction and relaxation
222
some calcium is stored in what?
sarcoplasmic reticulum
223
many smooth muscle cells contain what in the outer cell membrane?
calcium channels
224
what are calcium channels?
voltage-gated or ligand-gated channels
225
when calcium channels open what happens?
calcium diffuses in to initiate muscle contraction
226
what triggers calcium channels to open?
changes in membrane potential or presence of specific ligands
227
receptors for different ligands present on what muscle of different organs?
cardiac and smooth muscle
228
contraction produced only of organs with what for the specific ligand?
receptors
229
what are calcium channel blockers?
a type of drug
230
what do calcium channel blockers do?
bind to and inactivate calcium channels
231
what do calcium channel blockers do?
prevent influx of calcium and therefore contraction of smooth muscle/cardiac muscle
232
what does calcium channel blockers do to smooth muscle?
reduce the strength of contractions
233
where in smooth muscle are there calcium channels?
in the walls of many arteries
234
calcium channel blockers are effective to what in humans and animals?
lower blood pressure
235
what do calcium channel blockers do to cardiac muscle?
blocks influx of calcium ions
236
calcium channel blockers act to control what but slowing the rate of sinoatrial node discharge and the conduction velocity through the atrioventricular node?
arrhythmias
237
what are some calcium blocker drug examples?
verapamil and nifedipine
238
in cardiac muscle what is present?
actin and myosin
239
in cardiac muscle what branch and join in?
fibers (cells)
240
what so fibers, actin, and myosin do to form a network?
anastomose together
241
in cardiac muscle what is not as well developed?
sarcotubular system
242
what are intercalated disks?
provide connection between cardiac cells
243
what do intercalated disks do?
permit electrical transmission from one cardiac muscle cell to the next
244
what can readily spread from cell to cell allowing muscle to act electrical and mechanically as a functional syncytium
action potentials
245
high requirement for what in cardiac muscle?
ATP
246
ATP production is what?
aerobic
247
disruption of blood supply quickly results in what ?
myocardial ischemia and symptoms of heart attack
248
in cardiac muscles what is not required?
nerve stimulation
249
own intrinsic ability to generate action potentials via what?
pacemaker cells
250
what depolarizes faster than any other part of the heart muscle?
normal pacemaker is SA node
251
if SA node is diseased, what happens?
other pacemaker areas take over
252
what nerves alter or regulate heart rate which SA node normally sets
sympathetic and parasympathetic
253
cardiac muscle contraction slower than what and lasts longer as action potential?
skeletal muscle
254
in cardiac muscle the result is what kind of contraction?
slow and sustained contraction
255
in cardiac muscle tetany is what?
rare
256
what does slow and sustained contraction allow for in cardiac muscle?
filling and emptying of heart chambers
257
what does time delay allow for in cardiac muscle?
depolarization and relaxation of muscle
