Muscles Flashcards
2
Q
What are the 3 types of ‘CONTRACTILE TISSUE’ in the body?
A
- SMOOTH MUSCLE
- CARDIAC MUSCLE
- SKELETAL MUSCLE
3
Q
What are the 2 ‘RESPONSIBILITIES’ for the 3 types of contractile tissue in the body?
A
- MOVEMENT OF THE BODY
2. MOVEMENT OF MATERIALS IN BODY
4
Q
What do ‘MUSCLE CELLS’ give the body in general?
*3 THINGS
A
- FORM STABILITY TO BODY
- WORK IN OPPOSITION TO GRAVITY
- MAINTAIN BODY POSTURE
5
Q
What do ‘SKELETAL MUSCLE CELLS’ release as an end product?
A
HEAT
*END PRODUCT OF ‘METABOLISM’
6
Q
What muscle cells play a role in ‘TEMPERATURE REGULATION’?
A
SKELETAL MUSCLE CELLS
7
Q
What skin cells are all 3 ‘MUSCLE CELL TYPES’ ‘DERIVED’ from and what are they ‘COMPOSED’ of?
A
- DERIVED = MESODERM
2. COMPOSED OF = ‘CONTRACTILE FIBERS’ (ELONGATED CELLS)
8
Q
What is ‘MYOGENIC’ contraction defined as?
A
SPONTANEOUS CONTRACTION
9
Q
What is ‘NEUROGENIC’ contraction defined as?
A
INNERVATION CONTRACTION
10
Q
What are the 4 ‘CHARACTERISTICS’ of ‘SMOOTH MUSCLE’?
A
- ELONGATED
- ‘NO’ CROSS STRIATIONS
- INVOLUNTARY CONTROL
- ONLY ‘ONE’ NUCLEUS
11
Q
What are the 4 ‘CHARACTERISTICS’ of ‘CARDIAC MUSCLE’?
A
- ‘YES’ CROSS STRIATIONS
- ONLY ‘ONE’ NUCLEUS
- INVOLUNTARY CONTROL
- INTERCALATED DISCS
12
Q
What are the 4 ‘CHARACTERISTICS’ of ‘SKELETAL MUSCLE’?
A
- ELONGATED
- ‘MULTI’ NUCLEATED
- VOLUNTARY CONTROL
- WELL DEVELOPED ‘CROSS STRIATIONS’
13
Q
What is the ‘PRIMARY FUNCTION’ of ‘SMOOTH MUSCLE’?
Where are they ‘PRIMARILY LOCATED’?
A
- CONTRACTION OF INTERNAL ORGANS
2. PRESENT IN WALLS OF MANY ORGANS
14
Q
What is a ‘SYNCYTIUM’?
What ‘MUSCLE TISSUE’ is responsible for this?
A
WHEN ‘CARDIAC MUSCLE’ TISSUE BIFURCATES AND JOINS ADJACENT FIBERS.
CREATES ‘INTERCALATED FIBERS’
ONLY ‘CARDIAC MUSCLE’
15
Q
What is the function of ‘SYNCYTIUM ARRANGEMENT’?
Where are these located?
A
INTEGRATED/UNIFIED CARDIAC CONTRACTION.
*LOCATED WITHIN THE WALLS OF THE HEART
16
Q
What are the 4 ‘FUNCTIONS’ of ‘SKELETAL MUSCLES’?
A
- MOVEMENT OF BONES
- BODY POSTURE
- FACIAL EXPRESSION
- BREATHING MOVEMENTS
17
Q
Which type of ‘MUSCLE TISSUE’ makes up most of the muscles in the body?
A
‘SKELETAL MUSCLE’
18
Q
What is the only ‘MUSCLE TISSUE’ that is ‘MULTINUCLEATED’?
A
‘SKELETAL MUSCLE’
19
Q
What ‘MUSCLE TISSUE’ does ‘NOT’ have ‘CROSS STRIATIONS’?
A
‘SMOOTH MUSCLE’
20
Q
Under ‘MUSCLE TERMINOLOGY’ what is a ‘MUSCLE CELL’ called?
A
MUSCLE FIBER
21
Q
Under ‘MUSCLE TERMINOLOGY’ what is the ‘PLASMA MEMBRANE’ called?
A
MUSCLE SARCOLEMMA
22
Q
Under ‘MUSCLE TERMINOLOGY’ what is the ‘CYTOPLASM’ called?
A
MUSCLE SARCOPLASM
23
Q
Under ‘MUSCLE TERMINOLOGY’ what is the ‘ENDOPLASMIC RETICULUM’ called?
A
SARCOPLASMIC RETICULUM
24
Q
A ‘MUSCLE FIBER’ is broken down into 4 things. What is it broken down into from biggest to smallest?
A
MUSCLE FIBER -> (MYOFIB)RILS -> (MYOFIL)AMENTS -> ACTIN/MYOSIN
25
Q
A ‘MUSCLE FIBER’ is defined as what?
A
MANY SMALL/ROUND PARALLEL BUNDLES (100s-1000s) CALLED ‘MYOFIBRILS’
26
What are 'MYOFIBRILS' composed of?
MYOFILAMANETS
27
What are 'MYOFILAMENTS' composed of?
ACTIN (THIN)
| MYOSIN (THICK)
28
What parts of a 'MUSCLE FIBER' contain the 'CONTRACTILE PROTEINS'?
MYOFILAMENTS
29
What are the 'CONTRACTILE PROTEINS' in 'MUSCLE FIBERS' called?
(*THERE ARE 2 OF THEM)
1. ACTIN
| 2. MYOSIN
30
What are the 2 'PROTEINS' that are associated with 'ACTIN' called?
1. TROPONIN
| 2. TROPOMYOSIN
31
'CONTRACTILE PROTEINS' are arranged into 'COMPARTMENTS'. What are these called?
SARCOMERES
32
A 'SARCOMERE' has both 'dark' and 'light' striations. What are these caused by?
ARRANGEMENT OF 'ACTIN' AND 'MYOSIN'.
33
The 'DARK BANDS' in a 'SARCOMERE' are called what?
A-BANDS (ANISOTROPIC)
34
The 'LIGHT BANDS' in a 'SARCOMERE' are called what?
I-BANDS (ISOTROPIC)
35
TRUE OR FALSE
THE 'I-BAND' CONTAINS 'BOTH' ACTIN/MYOSIN.
FALSE
I-BAND = ACTIN ONLY
36
TRUE OR FALSE
THE 'A-BAND' CONTAINS 'BOTH' ACTIN/MYOSIN.
TRUE
A-BAND = ACTIN/MYOSIN
37
The 'LIGHTER CENTRAL REGION' of the 'SARCOMERE' is called what?
H-ZONE
38
What are the 3 'CHARACTERISTICS' of the 'H-ZONE'?
1. LIGHTER 'CENTRAL' REGION THAT IS CONNECTED TO THE 'A-BAND'
2. CONTAINS ONLY 'MYOSIN'
3. 'NO MYOSIN HEADS'
39
Which 'BANDS' of the 'SARCOMERE' are 'BISECTED' by 'Z-LINES'?
I-BANDS
40
What are the 3 'CHARACTERISTICS' of 'Z-LINES'?
1. AREA WHERE 'ACTIN' FILAMENTS OF ADJACENET SARCOMERES JOIN
2. 2 SUCCESSIVE 'Z-LINES' DEFINE THE LIMITS OF ONE SARCOMERE
3. DARK IN COLOR
41
TRUE OR FALSE
DURING 'MUSCLE CONTRACTION', ACTIN AND MYOSIN CHANGE IN LENGTH.
FALSE
ACTIN AND MYOSIN DO 'NOT' CHANGE IN LENGTH ONLY 'SARCOMERE CHANGES IN LENGTH'.
42
What happens to 'ACTIN' and 'MYOSIN' filaments during 'MUSCLE CONTRACTIONS?
(*3 THINGS)
1. ACTIN PULLED OVER MYOSIN
2. SARCOMERE LENGTH DECREASES
3. ACTIN/MYOSIN MAINTAIN LENGTH
43
Which band/zone has the following 'CHARACTERISTICS':
ACTIN
MYOSIN
DARK BAND
A-BAND (ANISOTROPIC)
44
Which 'AREAS' of 'MUSCLE CELL' line up?
DARK AREA & LIGHT AREA
45
Which band/zone has the following 'CHARACTERISTICS':
MYOSIN
LIGHT BAND
H-ZONE
46
Which band/zone has the following 'CHARACTERISTICS':
ACTIN
LIGHT BAND
I-BAND (ISOTROPIC)
47
When 'MUSCLE CONTRACTIONS' occur what type of 'MYOFILAMENT' is created?
THIN MYOFILAMENT
48
What is a 'MOTOR UNIT' composed of?
| *2 THINGS
1. SINGLE MOTOR NEURON
| 2. MUSCLE FIBERS IT INNERVATES
49
Can the muscle fibers in a 'MOTOR UNIT' vary?
YES
50
What types of muscles have very few 'MUSCLE FIBERS PER MOTOR UNIT'?
(APPROXIMATELY HOW MANY MUSCLES FIBERS ARE THERE)
MUSCLES CONCERNED WITH 'FINE', 'GRADED' AND 'PRECISE MOVEMENT'.
HANDS AND EYES = ~3-6 FIBERS/UNIT
51
What types of muscles 'many' 'MUSCLE FIBERS PER MOTOR UNIT'?
LARGE MUSCLES OF THE BACK = ~120-500 FIBERS/UNIT
52
What is a 'MYONEURAL JUNCTION'?
AXON OF A 'MOTOR NEURON'
53
What are the 'CHARACTERISTICS' of a 'MYONEURAL JUNCTION'?
| *3 THINGS
1. LOSES 'MYELIN SHEATH FROM 'MOTOR NEURON'
2. TERMINAL BUTTONS/END-FEET
3. COMPARABLE TO SYNAPTIC CLEFT
54
The 'END-FEET' or 'BUTTONS' of a 'MYONEURAL JUNCTION' contain what?
What 'NEUROTRANSMITTER' is released?
MANY SMALL, CLEAR VESICLES
NEUROTRANSMITTER = ACETYLCHOLINE
55
There are 6 events at a 'MYONEURAL JUNCTION', what are they?
| *SIMILAR TO SYNAPSE
1. ACTION POTENTIAL TRIGGERS ENTRY/RELEASE OF 'CALCIUM' INTO THE TERMINAL.
2. 'CALCIUM' TRIGGERS 'ACETYLCHOLINE' RELEASE
3. 'ACETYLCHLINE' DIFFUSES ACROSS SPACE/BINDS WITH RECEPTORS ON MUSCLE
4. 'SODIUM' CHANNELS OPEN GENERATING ACTION POTENTIAL
5. 'IMPULSE' FLOWS THROUGH MUSCLE CELL VIA 'TRANVERSE (T) TUBULE SYSTEM'
6. 'ACETYLCHLINE' BROKEN DOWN BY 'ACETYLCHOLINESTERASE
56
What are the 'DIFFERENCES' between a 'SYNAPSE' and a 'MYONEURAL JUNCTION'?
1. SYNAPSE = JUNCTION BETWEEN 2 NEURONS
2. MYONEURAL JUNCTION = NEURON AND MUSCLE CELL
3. 1:1 TRANSMISSION OF 'ACTION POTENTIALS' AT A 'MYONEURAL JUNCTION'
4. AT SYNAPSE POSSIBLE 'EPSP' OR 'IPSP' WHICH EFFECT 2nd NEURON
5. 'MYONEURAL JUNCTION' IS 'ALWAYS' EXCITATORY
57
TRUE OR FALSE
A 'MYONEURAL JUNCTION' IS ALWAYS 'EXCITATORY' AND NEVER 'INHIBITORY'
TRUE
'MYONEURAL JUNCTION' = ALWAYS EXCITATORY
(*THERE ARE NO EPSP/IPSP)
58
In a 'MYONEURAL JUNCTION', what triggers the 'exocytosis' or 'release' of 'ACETYLCHOLINE' from the vesicles?
CALCIUM
59
'ACTIN FILAMENTS' are composed of what 3 molecules?
1. ACTIN
2. TROPOMYOSIN
3. TROPONIN
60
What does 'G-ACTIN' stand for?
GLOBULAR ACTIN
61
What are 'GLOBULAR ACTIN' (G-ACTIN) molecules arranged into?
FIBROUS ACTIN (F-ACTIN)
62
What is 'FIBROUS ACTIN' (F-ACTIN)?
DOUBLE SPHERICAL CHAINS OF 'G-ACTIN'
63
What are the characteristics of 'TROPOMYOSIN'?
| *THERE ARE 3
1. LONG, THREAD-LIKE MOLECULES
2. LIE ALONG 'F-ACTIN' STRANDS
3. PHYSICALLY COVER ACTING BINDING SITES (DURING MUSCLE RESTING STATE)
64
How many 'G-ACTIN' subunits does one molecule of 'TROPOMYOSIN' cover?
7 'G-ACTIN' (GLOBULAR ACTIN) MOLECULES
65
What are the 'CHARACTERISTICS' of 'TROPONIN' molecules?
1. SMALL OVAL-SHAPED MOLECULE
2. ATTACHED TO EACH 'TROPOMYOSIN'
3. INVOLVED IN CALCIUM ION REGULATION
66
What are the 3 subunits of 'TROPONIN'?
1. TROPONIN-I
2. TROPONIN-T
3. TROPONIN-C
67
What is the function of the 'TROPONIN' subunit 'TROPONIN-I'?
BINDS TO ACTIN
68
What is the function of the 'TROPONIN' subunit 'TROPONIN-T'?
BINDS TO TROPOMYOSIN
| *HINT - (T) = (T)ROPOMYOSIN BINDING
69
What is the function of the 'TROPONIN' subunit 'TROPONIN-C'?
BINDS CALCIUM (INITIATES CONTRACTION)
| *HINT - (C) = (C)ALCIUM BINDING
70
Is 'ACTIN' thick or thin?
THIN
71
Is 'MYOSIN' thick or thin?
THICK
72
The 'MYOSIN CROSS BRIDGE' has 2 binding sites. What are they?
1. ACTING BINDING SITE
| 2. ATPase BINDING SITE
73
'MYOSIN FILAMENTS' (thick myofilaments) are composed of what 2 'COMPONENTS'?
1. LIGHT 'MEROMYOSIN' (LMM)
| 2. HEAVY 'MEROMYOSIN' (HMM)
74
What is the characteristic of 'LIGHT MEROMYOSIN' (LMM) filameNts?
MAKE UP THE 'RODLIKE' BACKBONE OF THE 'MYOSIN' FILAMENTS
75
What are the characteristics of 'HEAVY MEROMYOSIN' (HMM) filaments?
(*THERE ARE 2)
FROM SHORTER GLOBULAR LATERAL 'CROSS BRIDGES' (HEADS)
LINK WITH BINDING SITES ON 'ACTIN MOLECULES' DURING CONTRACTION
76
The 'SEQUENCE OF EVENTS' in 'MUSCLE CONTRACTION' can be summed up in what type of mechanism?
'SLIDING-FILAMENT' MECHANISM
77
The 'CROSS BRIDGES' of 'MYOSIN HEADS' are made of what?
HEAVY MEROMYOSIN (HMM)
78
During 'CONTRACTION' what is pulled over what?
'ACTIN' PULLED OVER 'MYOSIN'
79
Where are 'CALCIUM IONS' released during contraction of a muscle?
TERMINAL CISTERNAE
80
What is unique about the release of 'CALCIUM IONS' in 'MUSCLE CONTRACTION'?
AROUND 10x MORE THAN IS NEEDED TO INITIATE CONTRACTION IN MUSCLE IS RELEASED
'CALCIUM IONS' COMPLETELY SATURATE THE 'SKELETAL MUSCLE'
81
What molecules do 'CALCIUM IONS' released during 'CONTRACTION' bind to?
What does this cause to happen?
TROPONIN-C
'CONFORMATION CHANGE' OF 'TROPONIN' AND 'TROPOMYOSIN' MOVES TO ONE SIDE, EXPOSING 'ACTIN' BINDING SITES
82
What do 'MYOSIN CROSS BRIDGES' bind to?
ACTIN
83
When the 'MYOSIN HEAD' tilts due to a 'conformational change'. What is this also called?
'POWER STROKE' DUE TO 'SARCOMERE SHORTENING'
'ACTIN' FILAMENT PULLED OVER 'MYOSIN' FILAMENT
84
What happens after the 'POWER STROKE' occurs?
| *2 THINGS
'ATP' CAN BIND TO HMM (MYOSIN HEAD)
| CROSS-BRIDGES DETACH FROM 'ACTIN' BINDING SITES
85
What molecule causes the 'CROSS-BRIDGES' (MYOSIN HEADS) to detach from the 'ACTIN' binding site?
ATP
| USED TO 'RECOCK' AND 'ENERGIZE' THE MYOSIN HEAD
86
After a 'POWER STROKE' and after 'ATP' has detached 'MYOSIN HEAD' from 'ACTIN'. If 'CALCIUM IONS' are present in the muscle tissue, what will happen?
ANOTHER 'POWER STROKE' WILL BE PRODUCED
87
TRUE OR FALSE
During a single 'MUSCLE CONTRACTION', the sliding filament process occurs only once.
FALSE
RATCHET MECHANISM AND SLIDING FILAMENT PROCESS OCCUR 'REPEATEDLY' BETWEEN NUMEROUS BINDING SITES/MYOSIN CROSS BRIDGES DURING A 'SINGLE MUSCLE CONTRACTION'
88
Where is the 'ACTIVE CALCIUM PUMP' located?
What does it do?
'SARCOPLASMIC RETICULUM'
IT CONTINUALLY PUMPS 'CALCIUM IONS' OUT OF 'SARCOPLASM' BACK INTO THE 'TERMINAL CISTERNAE'
89
Without 'CALCIUM IONS' in the 'SARCOPLASMIC RETICULUM', what happens?
NO 'MUSCLE CONTRACTION' CAN OCCUR
MUSCLE IS AT A 'RELAXED STATE'
