1. Muscle Relaxation
-When the nerve impulse stops several things happen…
_____gets broken down by the enzyme _________________________ (found at the _____________________ junction).
Once ____is broken down, __________ions are transported back to the ______________ reticulum.
When the levels of _______ drops, linkages are no longer able to form between thin ________ and thick ________ filaments.
Since there are no ____________, the muscle ____________.

2. The relaxed and contracted sarcomereAA
Myosin head
Relaxation
Myosin – thick filament
Contraction
Actin – thin
filament
Muscle contraction animation

3. Neuromuscular Junctions
Every skeletal muscle cell is connected to an ________of a ________ __________.
_________ ______: a _______ _______and all of the ___________fibers it connects.

4. Parts of the Neuromuscular Junction
_____________________ ______________: The connection between the ________ _________ and the _________ _________.
________ ______ _________: specialized portion of the _________ fiber _________ , it is extensively _________ (to increase surface area) and contains many _______________.
_________ ______: the space between the _________ end plate (on the _________ fiber) and the _________ _________ , this “_________ ” is filled with a _________ material rich in _________.

5. Parts of the Neuromuscular Junction
_________ : end of the _________ cell
_________ : _________ sac formed by _________ in of the ____ membrane
_________________: _________ that are released at the end of a _________
______________(___): _________________that stimulates the muscle to _________

6. Neuromuscular Junction
Mitochondria
Synaptic
cleft
End-plate
of muscle cell

7. How the neuromuscular junction works
_________ impulses travel down the _________ to the _________ .
The ________________, Ach, is _________ in the _________ of the motor _________ .
When an impulse reaches the _________ of the _________ , the neuron releases ____________ (via vesicles) across the synaptic cleft.
The ______________binds to muscle _________ to stimulate a muscle _________ .
The muscle _________ is then sent in all directions over the _________ and through the _________ to the _________________ reticulum.

8. Neuromuscular junction and sarcoplasmic reticulum

9. Energy for Muscle Contraction
________________ oxidizes the sugar _________ and stores the _________ in the form of _____.
When _____ is exhausted for _________ contraction, _________ phosphate can transfer energy to ______.
Blood carries _________ to the _____________. _________ is carried on the _________ of red blood cells.
_________ debt may occur if the body cannot supply enough _________ for _________ muscles.

10. Energy for Muscle Contraction
Muscles use _________ respiration when they cannot get enough _________ .
_________  _________ acid + __ ATP
_________ is broken down to _________ acid which reacts to form _________ acid.
The build up of _________ acid can cause _________ and _______ in muscles.

11. When enough _________ is available, _________ respiration occurs.
Muscle _________ : muscle loses the ability to _________ due to a low _________ supply, exhaustion of _________________ , or accumulation of _________ acid.
_________ acid is broken down in the _________ and then used for _________ .