As it is passed from neuron to neuron through the different synapses, it reaches the neuromuscular junction. Where, the neurons send out specific messages to specific muscles at the distant parts of the body. In the case of flexing the right arm, the neuromuscular joint would cause the bicep to expand, while the triceps would relax. To lift the lower right arm the neuromuscular joint will have the bicep pull the hinge joint (the elbow joint) inward toward the body. (Jakab, 2006) Write how you trace the impulse, listing the steps in as much detail as possible, from which your brain sends the message to the appropriate muscles to reach up above your head to the shelf. Include in this the steps involved in the actual muscle fiber contraction sliding filament mechanism. Again, specify which muscles are pulling on which bones and what type of joints is involved.

When impulses are going from the muscle to the brain, the brain controls the intensity and how long the muscle will engage in such activities. However, once it is determined to allow the muscle to contract, the brain will send messages through...

When the muscle is contracting it will use sliding filament mechanisms. This is when myosin (a protein like substance that functions like a ratchet) allows the muscle to expand or contract at key joints. The myosin connects to different filimants (which connect to the joint) that allows for the muscle to easily contract. For example, when the brain decides to have the right forearm contract after flexing a muscle; an impulse will go from the central nervous system to the peripheral nervous system. The different neurons will transmit the message through the various synopses. Once it reaches the muscle groups of the right arm it will send impulses to the sliding filament mechanism, located near the hinge joint of the elbow. After the command to contract is given, the myosin will work in conjunction with the filaments that connect to the bicep and the triceps muscles. These will work in a ratchet like formation to move the lower right arm into place. (Jakab, 2006)
Bibliography

Jakab, C. (2006). Nervous System. North Mankato, MN: Smart Apple Media.