http://physiology.healthliberty.org Just another Health Liberty weblog Mon, 21 Apr 2008 09:06:05 +0000 http://backend.userland.com/rss092 en We will now look more closely at a muscle fiber, keeping in mind that there are thousands of these cylindrical cells in one muscle. Each muscle fiber has its own motor nerve ending; the neuromuscular junction is where the motor neuron terminates on the muscle fiber. The axon terminal is ... http://physiology.healthliberty.org/microscopic-structure-of-a-muscle-fiber/ Before discussing the contraction process itself, let us look first at how muscle fibers obtain the energy they need to contract. The direct source of energy for muscle contraction is ATP. ATP, however, is not stored in large amounts in muscle fibers and is depleted in a few seconds. The secondary ... http://physiology.healthliberty.org/energy-sources-for-muscle-contraction/ When you walk up a flight of stairs, do you have to look at your feet to be sure each will get to the next step? Most of us don't (an occasional stumble doesn't count), and for this freedom we can thank our muscle sense. Muscle sense (proprioception) is the ... http://physiology.healthliberty.org/muscle-sense/ Good muscle tone improves coordination. When muscles are slightly contracted, they can react more rapidly if and when greater exertion is necessary. Muscles with poor tone are usually soft and flabby, but exercise will improve muscle tone. There are two general types of exercise: isotonic and isometric. In isotonic exercise, muscles ... http://physiology.healthliberty.org/exercise/ Synergistic muscles are those with the same function, or those that work together to perform a particular function. Recall that the biceps brachii flexes the forearm. The brachioradialis, with its origin on the humerus and insertion on the radius, also flexes the forearm. There is even a third flexor of ... http://physiology.healthliberty.org/muscle-synergists/ Muscles are arranged around the skeleton so as to bring about a variety of movements. The two general types of arrangements are the opposing antagonists and the cooperative synergists. Antagonists are opponents, so we use the term antagonistic muscles for muscles that have opposing or opposite functions. The biceps brachii is ... http://physiology.healthliberty.org/muscles-antagonist/ All muscle cells are specialized for contraction. When these cells contract, they shorten and pull a bone to produce movement. Each skeletal muscle is made of thousands of individual muscle cells, which also may be called muscle fibers . Depending on the work a muscle is required to do, variable ... http://physiology.healthliberty.org/muscle-structure/ Do you like to dance? Most of us do, or we may simply enjoy watching good dancers. The grace and coordination involved in dancing result from the interaction of many of the organ systems, but the one you think of first is probably the muscular system. There are ... http://physiology.healthliberty.org/muscular-system/ Living cells constantly interact with the blood or tissue fluid around them, taking in some substances and secreting or excreting others. There are several mechanisms of transport that enable cells to move materials into or out of the cell: diffusion, osmosis, facilitated diffusion, active transport, filtration, phagocytosis, and pinocytosis. Some ... http://physiology.healthliberty.org/cellular-transport-mechanisms/ Cytoplasm is a watery solution of minerals, gases, organic molecules, and cell organelles that is found between the cell membrane and the nucleus. Cytosol is the water portion of cytoplasm, and many chemical reactions take place within it. Cell organelles are intracellular structures, often bounded by their own membranes, that ... http://physiology.healthliberty.org/22/