BIOS 252 Unit 8 Final Exam STUDY GUIDE WITH COMPLETE SOLUTIONS UPDATED 2023|2024 RATED A+

A. Muscle tissue function Produce body movements Stabilized body positions Storing and moving substances Generates heat B. Types of skeletal muscle proteins/function (p.300) Contractile Proteins a (generates force during contraction) Myosin: Makes up the thick filaments, consist of a tail and two myosin heads which binds to myosin binding site on acting molecule during contraction. Actin: Protein that is the main component of thin filament, each actin molecule has myosin –binding site, where myosis head of thick filament binds during contraction Regulatory Proteins (help switch muscle contraction on and off) Troponin. Component of thin filament, when calcium ions binds to troponin, it changes shape, this change moves tropomyosin away from myosin-binding on actin molecules Tropomyosin; Component of thin filament, when skeleton muscle fiber relaxed, tropomyosin covers myosin binding sites on actin molecules, preventing myosin from binding to actin. Structural Proteins; Keep thin and thick filaments of myofibrils in proper alignment Titin;Structure protein that connects z discs to M line of sarcomere helping to stabilize thick filaments positions, can stretch and spring back unharmed Dystrophin; Connects to the membrane protein Chapter 11: A. Steps in skeletal muscle contraction 1. Calcium binds to troponin, rotating tromyosin off the active site on actinng 2. Cross bridging occurs between the active site on the actin and myosin head. 3. Myosin head pivots toward the center of sarcomere pulling the Z lines closer causin the contraction. Release store energy, calcium pull out 4. Cross-bridging detachment the bond remains the same until the myosis head bind with another ATP molecule (rigor mortis) 5. Myosis activation the free myosis head splits the ATP into ADP and P which recooks the head again for the next cycle Calcium and ATP need it B. Definitions 1. Origin The attachment of a muscle or tendon to a stationary bone or the end opposite the insertion 2. Insertion Most muscle cross at least one joint and are attach at the articulating bone. 3. Antagonist Stretch or relax, triceps 4. Agonist Contract to control movement (bicepts), major muscle to produce an specific movement 5. Synergist Prevent unwanting movement during action 6. Fixator A muscle that stabilized the origin of the prime mover so that the prime mover can act more efficiently Chapter 12: A. Excitatory neurotransmitter function Graded depolarization cause by neurotransmitter binding to receptors in the postsynaptic neuron (more positive) Action potential (inward flow of Na+) B. Inhibitory neurotransmitter function