Term
| Somatic activates the _________ muscle and is mostly __________. |
|
Definition
|
|
Term
| Start at a muscle and go down to the Actin/Myosin |
|
Definition
- Muscle
- Fasicle
- Muscle Fibers (cells)
- Myofibrils
- Myofilaments (containing Actin and Myosin)
|
|
|
Term
| What are Neuromuscular Junctions (NMJ)? |
|
Definition
| Where the neurons release NT and bind to muscle receptors |
|
|
Term
| What is the Motor End Plate? |
|
Definition
| The muscles PM or Sacrolemma at the neuromuscular cleft |
|
|
Term
| What is a synaptic cleft called in a muscle? |
|
Definition
|
|
Term
| What kind of receptors are found on the Motor End Plate? |
|
Definition
|
|
Term
| What NT is released into the Neuromuscular Cleft? |
|
Definition
|
|
Term
| Binding of Ach on Cholinergic receptors always causes a _____________. |
|
Definition
|
|
Term
|
Definition
| A somatic motor neuron and all the muscle cells (fibers) it innervates |
|
|
Term
|
Definition
| The adding of more motor units in response to resistance |
|
|
Term
| Which bands get smaller and which ones don't in the Sliding Filament Theory? |
|
Definition
I-Band= Smaller
H-Zone= Smaller
Sarcomere itself = Smaller
A-Band = stays the same |
|
|
Term
| ____________ is an ATPase (enzyme) that hydrolyses ATP to a _______ and a _____. |
|
Definition
|
|
Term
| How many binding sites does Myosin have? |
|
Definition
2
One for Actin and one for ATP |
|
|
Term
| Myosin in the _________ position has more potential energy. |
|
Definition
|
|
Term
| What is the Cross-Bridge Power Stroke? |
|
Definition
| That which allows for sliding. |
|
|
Term
| What activates a myosin head? |
|
Definition
| The dephosphoralization of ATP into ADP and Pi |
|
|
Term
| When the ___ falls off the energy is released and the myosin head returns to the cocked position which pushes the _______ and then deactivates _________. |
|
Definition
|
|
Term
| Briefly describe the Cross-Bridge Power Stroke cycle. |
|
Definition
- Resting Muscle- Myosin activated, bond to ADP and Pi, but not to Actin yet.
- Calcium comes in- allows myosin to bind to actin
- Pi is released- myosin undergoes a confirmational change
- Power Stroke- as ADP dissociates
- ATP binds again allowing the dissociation between Actin and the Myosin head.
- ADP Hydrolysis- again activates the myosin head
|
|
|
Term
| If no more ATP is present, what state will the myosin head be in? |
|
Definition
| A state of constant contraction (Rigor) |
|
|
Term
| What other two proteins and ion are essential in muscle contraction? |
|
Definition
| Tropomyosin, Troponin and Ca++ |
|
|
Term
| Where can you find Tropomyosin? |
|
Definition
| Bound over the actin binding sites (this keeps myosin from being able to bind to actin) |
|
|
Term
| What role does Ca++ play in muscle contraction? |
|
Definition
| Ca++ binds to Troponin which moves it and Tropomyosin out of the way to allow myosin to bind to actin. |
|
|
Term
| What is the Sarcoplasmic Reticulum? |
|
Definition
| A lace-like network of tubules that surround the myofibrils and store intracellular Ca++ |
|
|
Term
| What are Transverse or T-tubules? |
|
Definition
| Tubules that are continuous with the PM and full of extracellular fluid |
|
|
Term
| What is Excitation-Contraction Coupling? |
|
Definition
|
|
Term
| Steps of Excitation-Contraction Coupling |
|
Definition
- Ach is released into the synapse by Somatic MN and Ach binds which opens Na+ channels
- AP moves into T-Tubules
- DHP Receptor is activated by AP
- BHP Receptor is linked to RyR and pulls it open- Ca++ diffuses out into cytoplasm
- Ca++ binds to Troponin- Moves Tropomyosin
- Actin and Myosin interact
- Shortening of Sarcomeres= Contraction
|
|
|
Term
|
Definition
| A muscle contraction, followed by a muscle relaxation. |
|
|
Term
| What is the Latent Phase? |
|
Definition
| The time between the muscle cell AP and the muscle contraction. |
|
|
Term
| What is happening during the Latent Phase? |
|
Definition
| The Excitation-Contraction Coupling |
|
|
Term
| The force of muscle contraction increases if you stimulate again before the end of relaxation is called_____________. |
|
Definition
|
|
Term
| What is Incomplete Tetanus? |
|
Definition
| Reaching the maximum tension of a muscle cell OR when many stimulations before the muscle can fully relax until it reaches its capacity |
|
|
Term
| What is Complete Tetanus? |
|
Definition
| Increased stimulation so that there is NO muscle relaxation which leads to fatigue. |
|
|
Term
|
Definition
| The absence of contraction even in the presence of a stimulus. |
|
|
