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Structure of a skeletal muscleMuscle is one of the four tissue types. The other three types are: epithelium, connective tissue and nervous tissue. The primary purpose of muscle tissue is to contract. Muscle contraction is used to move parts of the body, as well as to move substances within the body.
There are three general types of muscle. The first two are "striated", they contain sarcomeres; the third type is "smooth":
The differences in characteristics of the smooth muscles and the striated muscles include: the fibers of the smooth muscles are not arranged regularly as the ones of striated muscles, smooth muscles are use to sustain longer contraction or even near permanent whereas the striated muscles are often used for short, burst activities.
Muscles within the skeletal muscle are also divided in to two types of muscles: Type I and Type II muscles. Type I has a lot of myoglobin, hence the red color. It is good for endurance, because it is a place where lots of aerobic metabolismaerobic respiration. cellular respiration. A method by which living organisms metabolise fats or sugars with the aid of Oxygen in order to generate energy. Aerobic metabolism is rather more efficient than anaerobic metabolism. It actually starts off with takes place. It is a site where there is lots of mitochondria. Type II muscles are good for short-term activities that require lots of energy because it is good at generating power. However, this type of muscle is fatigues quickly due to anaerobic metabolism.
1 Contraction and relaxation
The three types of muscle have significant differences, but all use the movement of actinMicrofilament Actin is a contractile protein filament important for cell movements. It is expressed in all body cells, but especially in muscle cells. Actin can polymerize into microfilament, which are essential for the cytoskeleton, for cell motility, an against myosinMyosin is a contractile protein filament found in muscle tissue. Together with actin filaments, myosin provides the mechanism for muscle contraction, utilizing energy from ATP. Muscle is composed of muscle cells (sometimes known as "muscle fibers"). Withi to produce contraction and relaxation. In skeletal muscle, contraction is stimulated by electrical impulseselectrophysiological recording of an action potential showing the various phases which occur as the wave passes a point on a cell membrane. As the traveling signals of nerves and as the localized changes that contract muscle cells, action potentials are a transmitted by the nerveA nerve is an enclosed, cable-like bundle of nerve fibers or axons, which includes the glia that ensheath the axons in myelin. Neurons are sometimes called nerve cells though this term is technically imprecise since many neurons do not form nerves. Nervess, the motor nerves and motoneuronIn vertebrates, motoneurons (also called motor neurons are efferent neurons that originate in the spinal cord and synapse with muscle fibers to facilitate muscle contraction and with muscle spindles to modify proprioceptive sensitivity. Anatomy and physios in particular. All muscle contractions are facilitated by the neurotransmitterA neurotransmitter is a type of molecule that carries signals between neurons (nerve cells) at synapses in the nervous system. Neurotransmitters may be either excitatory ( EPSPs) or inhibitory ( IPSPs). That is, they may foster the initiation of a nerve i, acetylcholine. Muscles and muscular activity account for most of the body's energy consumption. Muscles store energy for their own use in the form of glycogen, which represents about 1% of their mass.
