BIO 446L 1st Edition Lecture10Outline of Last Lecture I. Muscle Tissuea. Muscle tissue types and innervationb. Skeletal musclei. developmentii. organizationc. Cardiac musclei. Organizationii. Anatomy of cardiac muscled. Smooth musclei. Anatomy of smooth muscleOutline of Current Lecture I. Musculoskeletal System 1a. Cartilageb. Bone types and markingsc. Superficial muscle structured. Muscle shapese. Muscle movementsf. Muscle contractioni. Neuromuscular junctionII. Musculoskeletal System 2a. Shoulder jointi. clavicleii. Scapulaiii. Humerusb. Innervation of the shoulderi. Movement at the glenohumeral jointii. Blood supplyc. scapulahumeral musclesd. deltoide. tres majorf. rotator cufg. gelenohumeral jointCurrent LectureThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.Musculoskeletal System 1- Skeletal Structureso Know axial and appendicular skeletono Know major bones and bones of the skull- Cartilageo Recall hyaline, reticular, and elastic cartilage and it’s compositiono Sternoclavicular joint is the only joint between the axial and upper appendicular skeleton and is lines with hyaline cartilage- Bone Types and Markingso Bone to bone is connected by ligamentso Bone types Long, short, sesamoid- Diference between long and short is that long bones are longer than they are wide, and short bones are just as long as they are wideo Know the definitions of the words head, protruberance, foramen, process, epiphysis, etc.- Superficial muscle structureo Muscle is connected to bone by tendonso Responsible for body form, movement, and heat productiono Know most of the muscles on the slideo Length of muscle includes the tendon- Muscle Shapeso Shape determines function i.e. circular muscle surrounding the eyeo aponeuroses= large, sheet-like tendon attached to abdomen muscles and muscles over the head, as well as down the leg attachment of muscle is very long- muscle movementso sarcomeres and muscle length (including tendon) need to shorteno muscles pull, never pusho prime mover and antagonist flex and extend muscleso isometric contraction= sarcomeres shorten but muscle length does not ex: pushing against somethingo isotonic contraction= load is fixed but muscle length shortens or lengthens ex: load is gravity and you raise and hold your arm upo eccentric contraction= gravity pulls limb down as muscle resistance decreases, contraction, but muscle lengthens ex: running downhill or putting an object down- Muscle contractiono Nerve at sarcomere synapseo Action potential fired, arrives at synaptic terminal, voltage change (depolarization), calcium channel opens, mobilized neurotransmitter (Ach) vesicles, exocytosis Ach receptor is ligand gated Na channel Ach esterase gets rid of Ach in synaptic cleft so muscle does not keep workingo You can pick up a feather and a suitcase because there are diferences in nerve fiber recruitment Nerve fibers make contact with diferent muscle fibers with right motor unitsMusculoskeletal System 2- Bones of the shoulder jointo Clavicleo Scapulao Humeruso *make a list of markings found on these bones—what are they used for in relation to moving the shoulder joint Ex: deltoid tuberosity—attachment of deltoid muscle- Innervation of shouldero Nerves are named according to where they leave the spinal cordo Brachial plexis Cervical portion of spinal cord Very close to cord, nerves begin branching and intertwining with each other- Ex: axillary nerve contains nerve fibers from several diferent nerves- This is why if one nerve is damaged, function of muscle movementcan often be maintainedo * learn which nerves supply which muscles- Movement at the glenohumeral jointo Of the 6 scapulohumeral intrinsic muscles, only one does not participate in shoulder rotation Supraspinatuso Glenohumeral joint= shoulder jointo Blood supply to the glenohumeral joint Know the suprascapular and axillary and their branches- Scapulohumeral muscleso See table 6.6 Tells muscle, innervation, and movemento All of these muscles have tendons that attach to the humerus- Deltoid muscleso Nonintrinsico Shoulder movemento 3 sections Medial—parallel to humerus Anterior and posterior—oblique to humerus- Teres major muscleso Nonintrinsico When contracts, adducts the arm- Rotator cuf muscleso See table 6.6o Scapula to head of humeruso SITS—acronym for the tendons- Glenohumeral jointo Also know acromioclavicular joint and sternoclavicular jointo Glenohumeral joins the scapula head of humeruso Very shallow joint relative to the job it does Cavity is small for head of joint Extensive layering of ligaments and reinforcing layer of tendons and bursa(surrounds some tendons and structures inside