Muscles PDF
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Summary
This presentation covers different muscle types, their composition, and functions in the human body. It details smooth, cardiac, and skeletal muscles, explaining their roles and structures.
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Muscles : C K A y // H od f. b...
Muscles : C K A y // H od f. b y o ert rop P Property of.body//HACK: Smooth muscle : C K Controlled by the autonomic nervous system H A (Involuntary) so is not under conscious//control d y. b o Used in all processes that maintain the body’s internal environment. o f rt y Found in the digestive system, it contracts to Found in p e move food through the body. r o blood vessels where it constricts & P to alter the flow of blood as well as dilates, urinary and reproductive systems Property of.body//HACK: Cardiac muscle : C K Found in the heart within the chamberHA y / / d walls where it pumps blood and Oxygen o around the body. f. b o The heart works continuously, y it is not r under conscious e t control. r o p The set rhythm of the heart (on average P 72 bpm at rest) is called autorhythmicity Property of.body//HACK: Skeletal muscle : C K They are striated in nature and cross over the joints and attach to the bones via //H A d y tendons. b o They are controlled by the.somatic nervous system so worko f under conscious rt y or voluntary control. p e P pull r o When stimulated to work, they contract, on the bones and create different body movements. Property of.body//HACK: Common terms : CK A Myo/My – A prefix denoting a relationship H to muscle y / / d Sarco - A prefix denoting flesh or o fleshy tissue, mainly referring to muscle f. b y o e r t r o p P Property of.body//HACK: Muscle composition : C K Water: 75-80% A y Protein (Elastin & Collagen): 20-25% // H od Fat: 1–10% f. b Glycogen: 1% y o ert rop P Property of.body//HACK: Muscle composition : C K A Myocytes (muscle fibers) form the bulk of muscle tissue. H y / / Myocytes are bound together by perimysium, a sheath o of connective tissue. Muscles aredcomposed of long bundles. b of Myocytes containingfthousands of myofibrils. y o Each Myofibril istcomposed e r of numerous sarcomeres o p Sarcomeres r are made up of myofilaments of the proteins P and Actin. Myosin Property of.body//HACK: Structure of a Muscle : C K A y // H od f. b y o ert rop P Property of.body//HACK: How muscles attach to bones : C K A y // H od f. b y o ert rop P Property of.body//HACK: Sliding Filament Theory : K C A A theory that helps explain how the muscles contract H y / / to generate force, based on the sliding movements of thin filaments (actin) alongo d filaments (myosin). thick f. b y o e rt r o p P Property of.body//HACK: Sliding Filament Theory : CK A Cocking: ATP breaks down releasing energy, so myosin’s head gets into a ‘cocked’ position. //H Binding: Calcium ions releaseoind y the Sarcoplasmic f Reticulum so myosin head. b attaches to actin. y o r t Power stroke: Myosin head rotates, pulling the actin towards theecentre of the sarcomere to generate r o p tension/muscle contraction. P Reset: ATP binds to the myosin head, releasing it from the actin binding site. Property of.body//HACK: Types of Muscle Contraction : C K A y // H od f. b y o ert rop P Property of.body//HACK: Types of Muscle Contraction : C K A y // H od f. b y o ert ro p P This means that the muscle is under tension. Contraction: Here the muscle may lengthen, shorten, or remain the same. Property of.body//HACK: Types of Muscle Contraction : C K Concentric: Eccentric: A // H Isometric: contraction contraction where y contraction where d where the muscle the muscle shortens. bo the muscle lengthens remains the same of rt y p e Pro Property of.body//HACK: Law of Reciprocal Inhibition : K C In order for a muscle on one side ofH A to contract y / / a joint effectively (Agonist), the o d System sends a Nervous f. b y o message to the muscle on the opposite side of that e r t joint (Antagonist) to relax. Otherwise, movement r o p P not be possible. would Property of.body//HACK: Law of Reciprocal Inhibition : C K A y // H od f. b y o ert rop P Property of.body//HACK: Law of Reciprocal Inhibition : C K A Fixators/stabilizers: Contracts to stabilize body part that remains fixed y // H Synergist: Contracts to assist o d f. b or modify the Agonist muscles y o e r t ro p P Property of.body//HACK: