Muscles Flashcards
1
Q
Muscle is an what type of tissue?
A
Excitable
2
Q
T/F there are different responses to a stimulus
A
True
3
Q
How does muscle contract?
A
through transmission of an AP
4
Q
to contract, muscle must take a _______ energy source and convert it to a ______ form of energy
A
biochemical, mechanical
5
Q
ATP creates what?
A
Movement
6
Q
there are how many types of muscle tissues
A
3
7
Q
how are muscle tissues/cells classified?
A
based upon microstructure of cell types
8
Q
what are the 3 types of muscle cells?
A
skeletal
cardiac
smooth
9
Q
what is the primary muscle cell type of the body?
A
skeletal
10
Q
T/F skeletal muscles are most similar to prokaryotic cells
A
False, theyre similar to eukaryotic cells
11
Q
What are the differences between skeletal muscles and basic eukaryotic cells?
A
enlongated cell body
multi-nucleated
more mitochondria
contains numerous sarcomeres
12
Q
what are the similarities between cardiac and skeletal muscle cells?
A
mitochondria density
contains numerous sarcomere
13
Q
what are the differences of cardiac muscle cells and skeletal muscle cells?
A
branched shaped
single nuclei
intercalated disk
14
Q
what is the purpose of intercalated disks in cardiac muscles cells?
A
support synchronization of contraction
15
Q
a skeletal muscle cell is also known as what?
A
muscle fiber
16
Q
what are the unique aspects of a muscle cell?
A
long and elongated
multinucleated
17
Q
what contains the sarcomere?
A
myofibril
18
Q
what is the unique rod-shaped organelle of muscle fiber?
A
the sarcomere
19
Q
what is the sarcomere composed of?
A
myosin
actin
regulatory and structural proteins
20
Q
Myosin is the what filament?
A
thickest
21
Q
actin is the what filament?
A
thin
22
Q
what is the smallest contractile unit of muscle?
A
sarcomere
23
Q
what is the sarcomere comprised of?
A
myosin and actin
24
Q
what are the 3 types of proteins within the sarcomere?
A
functional
regulatory
structural
25
what are the 3 domains of myosin
head
neck
tail
26
what isoform of myosin makes up the thickest filament of the sarcomere?
myosin 2
27
what are the two meromyosin chains
heavy
light
28
What are the two sections of heavy meromyosin?
s1 globular head
s2 neck domain
29
what binding are on the s1 globular head?
actin and ATP
30
What is found on the S2 neck domain?
myosin light chains
31
what is the role of regulatory light chain? (RLC)
structural integrity
32
what is the role of the essential light chain? (ELC)
structural integrity
role in binding site
33
what is the primary protein of the thin filament?
actin
34
T/F Actin makes up 25% of total skeletal muscle protein
False, its 20%
35
What is the base protein of actin
globular protein
36
what is a string of G-actin called
filamentous actin
37
what are the 2 primary regulatory proteins?
tropomyosin
troponin
38
T/F Tropomyosin is the master regulator of muscle contraction
True
39
what is the general structure of tropomyosin?
a-helical intertwined with F-actin protein
40
the troponin complex is anchored to _____
tropomyosin
41
what is the function of tropomyosin?
related to muscle contraction
42
what are the subunits of the troponin complex?
Troponin T, C, I
43
what is the function of troponin T?
anchors TC to TM
44
What is the function of TC?
regulatory control of TC and TM
activated by intracellular Ca^2+
45
what is the role of troponin I?
fulcrum of the TC
46
what makes up the dystrophin-glycoprotein complex?
dystrophin
glycoprotein
47
what is the function of the dystrophin-glycoprotein complex?
transfers intracellular force to the cell wall
48
desmin is a _______/______ protein
structural/mechanical
49
what is the role of desmin?
structural integrity
ties myofibrils together
mechanical force transmission
50
what is the largest protein of the body?
titin
51
T/F titin spans the entire length of the sarcomere
True
52
what is the role of titin in the sarcomere?
provides elasticity and ability to stretch during contraction
53
what are the unique organelles of the muscle fiber?
Sarcolemma
Sarcoplasmic reticulum
54
what is the plasma membrane of the muscle fiber called?
sarcolemma
55
the sarcolemma is similar to the plasma membrane of a _______
neuron
56
what channels are found in both sarcolemma and the membrane of a neuron?
voltage-dependent Ca^2+ channels
57
what is the sarcolemma connected to?
basement membrane of surrounding connective tissues
58
what are the invaginations of the sarcolemma called?
transverse-tubules
59
what is the role of transverse-tubules?
signal transduction
60
The transverse-tubules are a _______ of the sarcolemma
continuation
61
transverese tubules are located at the junction between which bands of sarcomere?
A-Band and I-Band
62
T/F the sarcoplasmic reticulum regulates Na+ homeostasis and activation of myofilament contraction
False, regulates Ca^2+
63
the sarcoplasmic reticulum is composed of parallel tubules running the length of the sarcomere. The tubules merge into _____ ______.
large cisterns
64
T/F the sarcoplasmic reticulum is a minor component of muscle contraction
False, major role
65
what is the communication epicenter of contraction in the sarcoplasmic reticulum?
triad junction
66
what important channels are located in jSR?
Ca^2+ releasing channels
67
where is the dihydropyrine receptor located?
transverse-tubules
68
the dihydropyridine receptor is sensitive to changed in ________
voltage
69
where is the ryanodine receptor located?
sarcoplasmic reticulum
70
what is the function of ryanodine receptor?
controls release of Ca^2+ into the sarcoplasm during contraction
71
T/F muscle contraction is a increase in muscle tension
True
72
what are the two types of contraction?
isometric
isotonic
73
what happens to muscle tension/length during an isometric contraction?
muscle develops/increases tension but does not change length
74
what happens to muscle tension/length during an isotonic contraction?
muscle develops/increases tension while changing length and generating force
75
what are the types of isotonic contractions?
concentric
eccentric
76
what are the characteristics of concentric contraction?
contraction that shortens the muscle and generates force
77
what are the characteristics of eccentric contraction?
contraction that elongates the muscle and generates force
78
T/F skeletal muscle is homogeneous
False, its heterogeneous
79
what are the primary type of muscle fibers?
type I, IIA, IIX/B
80
T/F every muscle is comprised of a combination of various fibers
True
81
what kind of neuron is innervated into a branch of muscle fibers
efferent
82
a branch of muscle fibers is ______
homogenous
83
the whole muscle is ______
heterogenous
84
T/F in terms of the organization of a single whole muscle itself is homogenous, and the muscle fibers are heterogenous
false, the whole muscle is heterogenous and the muscle fibers are homogenous
85
T/F the homogenous aspects of a motor unit allows for our bodies muscle to adapt to changing demands
True
86
what influences allow for muscle plasticity?
hormonal and neural
87
what influence the muscle fiber types within a muscle?
nerve activity
88
what are the primary forms of metabolism in muscle fibers?
oxidative and glycolytic
89
what is the main pathway of glycolytic metabolism?
glycolysis
90
what is the main pathway of oxidative metabolism?
cellular respiration
91
the conversion of glucose into pyruvate results in _______
production of ATP
92
where does glycolysis occur?
cytoplasm of the cell
93
in a general cell how much ATP is produced through glycolysis?
5 ATP
94
during cellular respiration, glucose is converted to ______
Biochemical energy or ATP
95
what are the 3 stages of cellular respiration?
glycolysis
pyruvate
TCA cycle
96
how many ATP are produced through cellular respiration?
30
97
T/F all muscle cells produce the same amount of ATP
False
98
how is energy stored within the muscle?
glucose-6-phosphate
99
in the muscle, glucose automatically goes through the first step of _________.
glycolysis
100
in the muscle, what enzyme converts glucose to glucose-6-phosphate?
hexokinase
101
hexokinase requires how many ATP for conversion to glycogen?
1 ATP
102
metabolic function within muscle is dependent upon _____
O2
103
in an anaerobic environment, glycolytic metabolism converts pyruvate to _______ and is then removed
lactic acid
104
what is pH sensitivity?
how well a muscle cell can function depending on pH of muscle
105
what defines the pH of a muscle fiber?
type of metabolism
106
fibers that utilize mainly what are susceptible to fatigue
glycolytic
107
fibers that primarily use what metabolism are more resistant to fatigue
oxidative
108
skeletal muscle have an ______
adaptive potential
109
what cause skeletal muscle to change fiber type?
hormonal and neural influence
110
what hormonal changes can change muscle?
endocrine regulators of muscle mass
111
how do neural changes impact muscle?
changes in neurotransmission
