Anatomy (BIOL 2220) Exam 3 – Cummings Questions and Answers 100% Pass

Anatomy (BIOL 2220) Exam 3 – Cummings Questions and Answers 100% Pass skeletal muscle - striated, voluntary, multinucleated cardiac muscle - striated, involuntary, uninucleated smooth muscle - nonstriated, involuntary, uninucleated properties of muscle - excitability, contractibility, extensibility, elasticity functions of muscle - motion, maintenance of posture, stabilizing joints, heat protection skeletal muscle composition - skeletal muscle fibers, blood vessels, nerve fibers, connective tissue direct attachment - muscle has contact with bone indirect attachment - extension between muscle and bone holds them together epimysium - dense irregular connective tissue covering muscle tendon - rope-like attachment from muscle to bone made of connective tissue EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 2 aponeurosis - sheet-like attachment from muscle to bone made of connective tissue origin - point of muscle contact with unmovable bone, almost always superior/proximal to insertion insertion - point of muscle contact with moveable bone, almost always inferior/distal to origin fascicle - chunk of muscle with connective tissue covering perimysium - connective tissue covering a fascicle muscle fiber - muscle cell endomysium - reticular connective tissue covering individual cells myofibers - muscle cells aka muscle fibers sarcolema - plasma membrane of muscle cell sarcoplasm - cytoplasm of muscle cell nuclei of skeletal muscle - multiple per cell, really long cells sarcoplasmic reticulum - modified endoplasmic reticulum, primarily runs parallel to fibers but some run perpendicular (terminal cisternae) T tubule - runs between two terminal cisternae terminal cisternae - sarcoplasmic reticulum tubes that run perpendicular to fibers EMILY CHARLENE © 2025, ALL RIGHTS RESERVED 3 myofibrils - configuration gives striation, made up of sarcomeres sarcomeres - made up of myofilaments myofilaments - made up of actin or myosin (proteins) sarcomere Z line - aka Z disk, ends of sarcomere sarcomere A band - entire length of thick myofilament sarcomere I band - only the thin myofilament sarcomere H zone - only the thick myofilament sarcomere M line - middle of the H zone thick myofilaments - myosin, consist of tail and 2 heads, one head is actin-binding site, one head is ATP-binding site thin myofilaments - actin, consist of myosin-bin