Download Physiology Exam #3 Muscle Physiology | BIOL 2150 - PRINCIPLES OF PHYSIOLOGY and more Quizzes Physiology in PDF only on Docsity!
Endomysium
space between muscle fibers"endo" = within TERM 2
perimysium
DEFINITION 2 is a sheath of connective tissue that groups muscle fibers into bundles or fascicles. "peri" = around TERM 3
epimysium
DEFINITION 3
- a layer of connective tissue-ensheathsthe entire muscle- It is composed of dense irregular connective tissue."DEEP fascia""epi" = above TERM 4
Tendon
DEFINITION 4
- continuation of fascia- origin / insertion-connects muscle to bone TERM 5
sarcolemma
DEFINITION 5
- the cell membrane around the muscle cell
"A" band
- anisotropic-myosin and some actin TERM 7
"I" band
DEFINITION 7 -isotropic-no myosin TERM 8
"M" band
DEFINITION 8 -holds myosin together TERM 9
"H" band
DEFINITION 9 -no actin TERM 10
"Z" band
DEFINITION 10
What are filaments of a muscle
cell?
they are the cilia and flagella that contain myosin and actin TERM 17
What is Dystrophin?
DEFINITION 17 a type of protein found in muscles used for movement(only in skeletal andcardiac) TERM 18
What are the two contractile Proteins of the
Myofibril?
DEFINITION 18 -myosin-actin TERM 19
What are the two Regulatory Proteins of
Myofibril?
DEFINITION 19 -troponin-tropomyosin TERM 20
What are the Giant Accessory Proteins of
Myofibril?
DEFINITION 20 -titin-nebulin
Microfilaments
- the thinnest filaments of the cytoskeleton-more specifically they are highly organized bundles of contracile and elastic proteins that carry out the work of contraction (so myosin and actin) TERM 22
What does the sarcoplasm mitochondrion
do?
DEFINITION 22 the sarcoplasm mitochondrion stores glycogen TERM 23
sliding filament theory
DEFINITION 23 -Ca++ binds to troponin-Uncovers binding site on actin- Activated myosin attaches- Myosin head flexes = sliding of actin toward M line TERM 24
What are the tree Muscle Action Potential
Phases?
DEFINITION 24 -Latent = (AP to onset of contraction)-Contraction-Relaxation TERM 25
What are the three Variations of Muscle AP
Phases?
DEFINITION 25 -speed to contractions of muscle fibers-height (force and strength)-duration
What is Asynchrony? And what type of
contractions is it associated with?
a way of avoiding fatigue by alternating motor units to allow some rest between contraction.prevents fatigue only in sub-maximal contractions TERM 32
What is the Optimal Length of a
Muscle?
DEFINITION 32 -the length at which you get max force TERM 33
SEE: series elastic element
DEFINITION 33 All muscles contain elastic fibers in the tendons and other connective tissue that attach muscles to bone, and in the connective tissue between muscle fibers. All of these elastic components behave collectively as if they were connected in a series to the contractile elements of the muscle. TERM 34
What is Isomeric Contraction? And what does
it create?
DEFINITION 34 Isomeric contraction is a type of contraction without a change in length of tendons, connective tissue, titin, etc. So they all are the same length.This isomeric contraction creates FORCE without movement. TERM 35
What is Isotonic contraction? What can it
do?
DEFINITION 35 A type of contraction without a change in force. aka remains the same tone throughout.Isotonic contraction is used to move loads
What does Concentric mean?
concentric means the shortening of muscles TERM 37
What does Eccentric mean? And what can
happen to this that is not a good thing?
DEFINITION 37 Eccentric means the stretching of musclesif you contract at the same time you stretch it is bad TERM 38
What is the Lever- Fulcrum formed by?
DEFINITION 38 formed by bones and muscles around joints TERM 39
What are Lever-Fulcrum Disadvantages?
DEFINITION 39 the muscle is required to make large amounts of force to move or resis t a small load TERM 40
What are Lever-Fulcrum Advantages?
DEFINITION 40 -it maximizes speed and mobility-If the muscle is inserted farther from the joint, the leverage is better and a contraction creates more rotational force
Type I Skeletal Muscle
slow twitch-oxidative-myoglobin (red muscle) TERM 47
Type IIa Skeletal Muscle
DEFINITION 47 -fast twitch-oxidative TERM 48
Type IIb Skeletal Muscle
DEFINITION 48 -fast twitch-glycolic-white muscle- high glycogen TERM 49
Types of Skeletal Muscle: Facts
DEFINITION 49 -most muscles have all three in varying proportions-motor units only innervate one type-you can't change which one you genetically have more of-but with plasticity , endurance training can determine fiber composition TERM 50
What type of athletes are associated with
Slow twitch?
DEFINITION 50 endurance athletesdistance runnerscross country
What types of athletes are associated with
Fast Twitch?
sprintersice hockeyweight lifters TERM 52
What is Hypertrophy and what does this do to
muscles?
DEFINITION 52 increased growth in muscle fibers,increase in number of actin & myosin (sarcomeres); this is how muscles get bigger. -larger diameter TERM 53
Hyperplasia allows muscles to what? But not
what?
DEFINITION 53 -muscle can split not divide 1) c TERM 54
Atrophy causes what four things in the
body?
DEFINITION 54 -lack of blood supply-muscle fibers get smaller-lack of nerve supply-immobility~ 1 year: muscle cells lose their actin/myosin & becomes fat. Longer than one year usually permanent damage. TERM 55
Muscular Dystrophy
DEFINITION 55 -Inherited muscles are the most difficult to treat. -Duchenne: no dystrophin to link actin to proteins in the cell membrane; very bad!!-tiny tears in membrane allows extracellular Ca++ to leak into the fiber, leads to progressive muscle weakness.-Becker: Dystrophin malformed; membrane leaks out Ca++ and muscle deformed = fibrosis (scar tissue)
The slow wave of a smooth muscle
membrane potential has what two
components located where?
The slow wave membrane potential of a smooth muscle show the depolarization and re-polarization below threshold with occasional AP TERM 62
Relaxation in Smooth Muscle
DEFINITION 62
- Free Ca++ in cytosol decreases when Ca++ is pumped out of the cell or back in to SR 2. Ca++ unbinds from Calmodulin (CaM) 3. Myosin phosphatase removes phosphate from myosin, which decreases myosin ATPase activity. 4. Less myosin ATPase results in decreased muscle tension. TERM 63
Two Types of Smooth Muscle
DEFINITION 63 -Single Unit-Multi Unit TERM 64
What do Joint Capsule Receptors (muscle
afferents) do?
DEFINITION 64 Tell the cerebellum and medulla the position of the body to keep posture/balance. TERM 65
Where are Golgi tendon Organs found?
(muscle afferents)
DEFINITION 65 -in tendons
muscle "afferents"
- going into the muscle TERM 67
What are Extrafusal muscle
fibers?
DEFINITION 67 they are standard muscle fibers ((aka not intrafusal muscle fibers)) TERM 68
What are Intrafusal muscle fibers? (muscle
afferents)
DEFINITION 68 -skeletal muscle fibers that comprise the muscle spindle TERM 69
What does the Stretch of spindle apparatus in
muscle lead to? AND what does that increase?
DEFINITION 69 -A stretch of a spindle apparatus leads to intrafusal stretch- this increases afferent impulses TERM 70
What is an alpha stimulated spindle?
DEFINITION 70 a muscle contraction
paraplegia
an impairment in motor or sensory function of the lower extremities. The word comes from Ionic Greek: -- "half- striking". ***does not effect the arms TERM 77
quadriplegia
DEFINITION 77 -paralysis caused by illness or injury to a human that results in the partial or total loss of use of a ll their limbs and torso TERM 78
spastic paralysis
DEFINITION 78 Spasticity is a feature of altered skeletal muscle performance in muscle tone involving hypertonia; it is also referred to as an unusual "tightness", stiffness, and/or "pull" of muscles. TERM 79
flaccid paralysis
DEFINITION 79 is a clinical characterized by weakness or paralysis and reduced muscle tone without other obvious cause (e.g., trauma). TERM 80
wave summation
DEFINITION 80 -occurs when a given set of cells is repeatedly stimulated without complete relaxation
tetany
is the sustained contraction resulting from high frequency stimulation TERM 82
skeletal muscle contract due to response to
what?
DEFINITION 82 they contract due to a response to Ach from a somatic motor neuron TERM 83
Do single or multiple pathways influence
smooth muscles contraction/relaxation?
DEFINITION 83 multiple pathways influence contraction/relaxation TERM 84
When do skeletal muscles
relax?
DEFINITION 84 They relax when stimuli from contraction ceases TERM 85
What can inhibit smooth muscles?
DEFINITION 85 -multiple neurotransmitters-hormones-paracrinesall acting on a smooth muscle can inhibit it
Do hormones control skeletal muscle
contractions?
no hormones do not control skeletal muscle contractions TERM 92
Which two types of muscles have multiple
layers of control?
DEFINITION 92 cardiac and skeletal muscles have multiple layers of control TERM 93
Do skeletal muscles have striated muscle
tissue?
DEFINITION 93 Yes, skeletal muscles have striated muscle tissue TERM 94
Are skeletal muscles under involuntary or
voluntary control?
DEFINITION 94 skeletal muscles are under voluntary control TERM 95
Which system controls skeletal muscles?
DEFINITION 95 the somatic nervous system controlsskeletal muscles
Are cardiac muscles involuntary or
voluntary?
cardiac muscles are involuntarily controlled TERM 97
Are cardiac muscles striated or
not?
DEFINITION 97 cardiac muscles ARE striated TERM 98
Where are cardiac muscles
found?
DEFINITION 98 cardiac muscles are found in the walls of the heartspecifically found in the myocardium TERM 99
Are skeletal muscle fibers single or multi-
nucleated cells?
DEFINITION 99 skeletal muscle fibers are multi nucleated cells TERM 100
What is Myofibril?
DEFINITION 100 a basic rod like unit of muscle
