Question

Be able to describe the structure of skeletal muscle, the proteins involved, how they contract and what leads to the initiation of contraction and relaxation of the muscle. Describe how muscles are named, give several examples of uniquely named muscles. Describe how muscles must work in agonistic and antagonistic ways to support movement. Discuss the different muscle fiber types, and how they contribute to strength and endurance. Describe the other muscle types (cardiac and smooth) compare and contrast the similarities and dissimilarities with skeletal muscle.

Answer 1

Each skeletal muscle fiber is a single cylindrical muscle cell, which made up of hundreds, or thousands, of muscle fibers bundled together and wrapped in a connective tissue covering. Each muscle is surrounded by a connective tissue sheath called the epimysium. Fascia, connective tissue outside the epimysium, surrounds and separates the muscles. Epimysium project inward to divide the muscle into compartments. Each compartment contains a bundle of muscle fibers. Each bundle of muscle fiber is called a fasciculus and is surrounded by a layer of connective tissue called the perimysium. Within the fasciculus, each individual muscle cell, called a muscle fiber, is surrounded by connective tissue called the endomysium

muscles are named by the action the muscle performs.examples are, are flexor and extensor, abductor and adductor; levator and depressor; supinatorand pronator; sphincter, tensor, and rotator muscles.

A flexor muscle decreases the anterior angle at a joint, an extensor increases the anterior angle at a joint, abductor moves a bone away from midline, adductor moves a bone closer to the midline, alevator raises a structure, a depressor moves a structure down, supinator turns the palm of the hand up, pronator turns the palm down, sphincter decreases the size of an opening, tensor tenses a body part, a rotator turns a bone around its axis.