Test 2 Class Notes - Anatomy and Physiology Class Notes...

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Anatomy and Physiology Class Notes Test #2 Lecture 1 Muscle and Nervous System All muscles have a point of origin (that from which they originate) and a point of attachment (this is called the insertion ). Usually, the point form where the muscle originates is closer to the midline of the body (distal, proximal). What are characteristics that all muscles must have?
Let’s discuss the anus gastroc nemius (your calf muscle)
This is not homogeneous so it will not have the consistency of a Jell-O, etc. this means that there is something in there. A skeletal muscle cell is a living , dynamic cell. Each one of these individual cells will have a cell membrane, and all around it will be connective tissue. So, there will be connective tissue surrounding the cells. In this case, some connective tissue will break the muscle cell into fascicles, and some will be the outer connective tissue. The outer connective tissue is called the epimysium (epi the outside). That which breaks it into fascicles will be called the perimysium. And that which surrounds each individual cell is called the endomysium. The connective tissue that is associated with muscle is almost as important as the muscle itself. We want the cells and units to shorten uniformly so that it pulls on the tendon, so as a result of pulling uniformly we will be able to move. Only these cells, which are like little machines, can do that shortening. If they were adhering directly to the heel, you would rip them up anytime you tried to move. The purpose of the connective tissue is to take the stress/strain of moving and anchor it. At the same time, the connective tissue is the place that will allow important other structures (blood vessels, nerves, lymphatic’s) to reside. If we want to get the muscle cell to shorten and lengthen, we have to provide energy in the form of glucose (ATP) endlessly

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