Muscular System: Muscles(Chapter 11)Lecture MaterialsforAmy Warenda Czura, Ph.D.Suffolk County Community CollegeEastern CampusPrimary Sources for figures and content:Marieb, E. N. Human Anatomy & Physiology 6th ed. San Francisco: Pearson BenjaminCummings, 2004.Martini, F. H. Fundamentals of Anatomy & Physiology 6th ed. San Francisco: PearsonBenjamin Cummings, 2004.Amy Warenda Czura, Ph.D.1SCCC BIO130 Chapter 11 Lecture SlidesMuscle Organization-groups of fibers organized into fascicles-fibers in fascicle run parallel to fascicle, butfascicle can be arranged in 4 differentshapes with respect to tendon:1. Parallel muscles-fascicles run parallel to length of muscle-most skeletal muscles arranged this way-able to change length extensively-can move load over a great distanceAmy Warenda Czura, Ph.D.2SCCC BIO130 Chapter 11 Lecture Slides2. Convergent muscles-fascicles spread out like fan on one end andconverge to single point on other-produces less tension and distance thanparallel muscle but- independent contraction of fascicles canproduce different movements from same muscle-provides versatilityAmy Warenda Czura, Ph.D.3SCCC BIO130 Chapter 11 Lecture Slides3. Pennate muscles (“feather like”)-fascicles are arranged at an angle to tendonA. Unipennate =fascicles angled on one side of tendonB. Bipennate =tendon in middle with angled fascicles oneither sideC. Multipennate =branched tendon with fascicles organizedaround each branch-pennate muscles produce more tension thanparallel muscles but cannot move as farAmy Warenda Czura, Ph.D.4SCCC BIO130 Chapter 11 Lecture Slides4. Circular muscles (sphincters)-concentric arrangement of fascicles-function to decrease diameter of openings,guard entrances and exitsMuscle TerminologyOrigin = where the fixed end of the muscleattaches to bone, cartilage, or CTInsertion = where the moveable end attachesAction = the specific movement produced bythe muscle during contractionAmy Warenda Czura, Ph.D.5SCCC BIO130 Chapter 11 Lecture SlidesMuscles often work in groups to increasetension or fine tune movement.Different muscles serve different functions:Agonist = prime mover, muscle mostresponsible for the specific actionSynergist = a muscle with the same action asthe agonist, assists agonist at thebeginning of contraction when fiberlength is not optimal for agonistAntagonist = a muscle whose action opposesthe agonist: produces the oppositeaction to fine tune movement by theagonistAmy Warenda Czura, Ph.D.6SCCC BIO130 Chapter 11 Lecture SlidesNames of muscle derived from aspects of theirfeatures:1. Location: named for part of body wherelocated e.g. Brachii, Abdominis2. Fascicle organization: named for howfascicles are organized with respect tobody e.g. Rectus = straightOblique = angle3. Relative position: named for depth whenlayered e.g. Externus/ Superficialis =top, surface Internus/ Profundus =deep4. Structure, Size and Shape: A. Number of tendonse.g. triceps, biceps B. Shape of musclee.g. trapezius = trapezoid deltoid = triangle soleus = fishAmy Warenda Czura, Ph.D.7SCCC BIO130 Chapter 11 Lecture SlidesC. Size of muscle relative to othersMajor = biggerMaximus = biggestLongus = longVastus = great5. Origin and Insertion: name for regions ofattachment, origin first, insertion seconde.g. Sternocleidomastoidorigin = manubrium of sternum andmedial clavicleinsertion = mastoid process6. Action: named for action performed and region acted upone.g. Extensor digitorumUsually multiple naming schemes arecombined to name the muscle:e.g. flexor carpi ulnaris*Individual muscles, origins, insertions andactions will be examined in detail in lab!Amy Warenda Czura, Ph.D.8SCCC BIO130 Chapter 11 Lecture