Broadly considered, human muscle—like the muscles of all vertebrates—is often divided into striated muscle (or skeletal muscle), smooth muscle, and cardiac muscle. Muscle is a specialised soft tissue, one of the four basic types of animal tissues. There are three types of muscle tissues in vertebrates: skeletal muscle tissue, cardiac muscle tissue, and smooth muscle tissue. Muscle tissue gives skeletal muscles the ability to contract and relax. Muscles are pieces of soft tissue throughout your body. They help you do everything from holding your body still to running a marathon. Muscles also move and support your organs. Your heart is a hard-working muscle that beats thousands of times a day to keep you alive. There are three types of muscle tissue: Visceral, cardiac, and skeletal. Visceral muscle is found inside of organs like the stomach, intestines, and blood vessels. The weakest of all muscle tissues, visceral muscle makes organs contract to move substances through the organ. Explore human muscle anatomy in detail, including functions, major muscle groups & how muscles support movement, strength & body stability. For related background details, please refer to our report on wiring a three way toggle switch. Heart muscle is striated muscle but is distinct from skeletal muscle because the muscle fibers are laterally connected. Furthermore, just as with smooth muscles, their movement is involuntary. A muscle is a group of muscle tissues which contract together to produce a force. A muscle consists of fibers of muscle cells surrounded by protective tissue, bundled together many more fibers, all surrounded in a thick protective tissue. Muscle is contractile tissue grouped into coordinated systems for greater efficiency. In humans the muscle systems are classified by gross appearance and location of cells. The three types of muscles are striated (or skeletal), cardiac, and smooth (or nonstriated).

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