Use LEFT and RIGHT arrow keys to navigate between flashcards;
Use UP and DOWN arrow keys to flip the card;
H to show hint;
A reads text to speech;
33 Cards in this Set
- Front
- Back
|
Characteristics of Muscle |
Excitablility(Responsivness): Nerve Conductivity: Contractility: Can contract Extensibility: Stretches Elasticity: Recoils |
|
|
Skeletal Muscle |
Voluntary, Striated muscle attached to bones. |
|
|
Myofiber
|
Muscle fibers |
|
|
Epimysium |
aka Fascia |
|
|
perimtsium |
Around each fascicles |
|
|
Endo museum |
Between each muscle fiber |
|
|
Synapse |
Where two cells meet |
|
|
Neuromuscluar Junctions |
Where a nerve fiber makes a s functional connection with its target muscle cell |
|
|
Components of Synapse |
*Synnaptic knob (contains acetylcholine) * |
|
|
Electrically excitable cells |
Plasma membrane is polarized/charged (resting membrane potential) Due to imbalance of charged ions. |
|
|
Muscle stages of contraction and relaxation |
1. Excitation 2. Excitation-Contration 3. Contraction 4. Relaxation |
|
|
Excitation |
1. Action Potentional (AP) arrive at neuromuscular lunch ion (NMJ) 2. AP opens voltage-gated calcium channels on synaptic knob. 3. Calcium enter synaptic knob and triggers exocytosis of synaptic vesicles containing ACh(Acetylcholine). 4. ACh enters synaptic cleft 5. ACh binds to ACh receptors on motor end-plate( part of sacrolemma) 6. Opens ligand-gated Na channels. 7. Na influx followed quickly by K efflux 8. AP spreads across sacrolemma |
|
|
Depolarization |
When you go from negative to positive in cell |
|
|
Repolarization |
When you go from positive to negative in cell. |
|
|
Excitation-Contraction Coupling |
1. AP propagates (spreads) down the T-Tubules 2. AP triggers release of calcium from terminal cistermea of SR (Sacroplasmic reticulum) |
|
|
Contraction |
Power stroke, shows myosin e=heads releasing ADP and phosphate |
|
|
Relaxation |
Cessation of nervous stimulation and ACh release, ACh Breaks down by AChe |
|
|
Rigor Mortis |
Stiffening of body after death due to loss of ATP |
|
|
Muscle Metabolism |
ATP is generated by |
|
|
Anaerobic Pathway |
2 ATP for each glucose |
|
|
Muscle fatigue |
Inability to contract. |
|
|
Oxygen Deficit |
Extra O2 needed for O2 reserve Glycogen stores, and ATP and CP reserves |
|
|
Heat production during muscle activity |
60%.... |
|
|
Three types of Mucle cells |
Slow oxidative fibers (Red): Endurance, Slow Fast Oxidative Fibers(Red/Pink): Sprinting/Walking Fast glycolytic: (Pale) Quick actions. |
|
|
Principles of Mucle Mechanics |
Contraction may/may not shorten muscle Isometric contraction: No shortening; Mucle tension increases but does not exceed load Isotonic: mucles shortening because Mucle tension exceeds load. |
|
|
Motor unit |
Motor neuron and all muscle fibers it supplies. |
|
|
Three phase of Mucle twitch |
Latent: Period excitation and contraction Contraction: Relaxation: |
|
|
Temporal (wave) summation |
Increased stimulus frequency( muscle does not completely relax between stimuli) >>> Second contraction of great force |
|
|
Tenany |
Maximal tension reached |
|
|
Recruitment |
Controls force of contraction (multiple motor unit summation) |
|
|
Isotonic Contractions |
Muscle changes in length and moves load Concentric contractions: muscle shorten and does work
Eccentric contractions: Muscle lengthens whilst maintaining tension. |
|
|
Isometric |
Muscle does not " " in length |
|
|
Muscle tone |
Optimum resting length (actin and myosin, still overlap, to prepare to be used) |
