Midterm Study Guide Anatomy And Physiology Bios252

Midterm Study Guide Anatomy and Physiology BIOS252 Chapter 11 A.Muscles 1.Gastrocnemius (location)- back portion of the lower leg, being one of the two major muscles that make up the calf. 2.Muscles that make up the Hamstrings-Biceps Femoris, Semitendinosus, and Semimembranosus 3.Tibialis(location)- largest muscle located in the anterior(front)compartment of the leg 4.Brachialis (function)- muscle in the upper arm that flexes the elbow joint. 5.Deltoid (function)- Contraction of the anterior fibers flexes and medially rotates the arm by pulling the humerus towards the clavicle. Flexion and medial rotation of the arm moves the arm anteriorly (throwing a ball underhand). The lateral fibers abduct the arm by pulling the humerus toward the acromion (reaching out to the side). Contraction of the posterior fibers extends and laterally rotates the arm by pulling the humerus toward the spine of the scapula (reaching backwards or winding up to throw a ball underhand). Chapter 12 A.Types of myelinated fibers Axis cylinder forms the central core of the fiber. It consists of axoplasm covered by axolemma. Myelin sheath derived from Schwann cells, surrounds the axis cylinder. 1Neurolemmal sheath (sheath of Schwann) surrounds the myelin sheath. It represents the plasma membrane (basal lamina) of the Schwann cell. Neurolemmal sheath