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The Muscle System

The Muscle System - Notes Notes The Muscular System The...

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Unformatted text preview: Notes Notes The Muscular System The Chapter 36 Section 2 Lecture Outline – The Muscular System PowerPoint Notes textbook questions Keys Keys Muscle System Functions Muscle Provides voluntary Provides movement of body movement Enables breathing, Enables blinking, and smiling blinking, Allows you to hop, Allows skip, jump, or do push-ups Maintains posture Produces heat Functions Continued Functions Causes heart beat Directs circulation Directs of blood Regulates blood pressure pressure Sends blood to Sends different areas of the body the Functions Continued Functions Provides movement of Provides internal organs internal Moves food through Moves digestive tract digestive Enables bladder control Causes involuntary actions Reflex actions Reflex Adjusts opening of pupils Causes hair to stand on Causes end ( ) end Muscle Tissue Characteristics Muscle Is made up of contractile Is fibers fibers Provides movement Controlled by the Controlled nervous system nervous Voluntary- consciously Voluntarycontrolled controlled Involuntary- not under Involuntaryconscious control conscious Examples Skeletal Smooth Cardiac Skeletal Smooth Cardiac Types of Muscle Tissue Types There are There three main types of muscle tissue muscle Skeletal (striated) Cardiac (heart) Smooth (visceral) Comparison of Muscle Types Comparison Muscle Type Skeletal Location Attached to Attached bone bone Heart Walls of internal Walls organs + in skin organs Function Movement of Movement bone bone Beating of heart Movement of Movement internal organs internal Control Mode Voluntary Involuntary Involuntary Long + slender Branching Spindle shape Striated- light Striatedand dark bands and Many nuclei Striated One or two One nuclei nuclei Non-striated One nucleus (visceral) Shape Characteristics Cardiac Smooth Frontalis Location of Muscles Muscles Skeletal Muscles Anterior Anterior view view Masseter Deltoid biceps brachii Pectoralis Major Brachioradialis External Obliques Rectus abdominis Quadriceps Group Quadriceps Quadriceps group group Tibialis Anterior Location Location of Muscles Trapezius Triceps brachii Skeletal Muscles Latissimus dorsi Posterior view Gastrocnemius Hamstring Hamstring Hamstring group group group Gluteus Gluteus maximus maximus Muscles You Need to Know 1. brachioradialis 1. 2. biceps brachii 2. 3. deltoid 3. 4. external oblique 4. 5. frontalis 5. 6. gastrocnemius 6. 7. gluteus maximus 7. 8. hamstring group 8. 9. latissimus dorsi 9. 10. masseter 11. pectoralis major 12. quadriceps group 13. rectus abdominis 14. tibialis anterior 15. trapezius 16. triceps brachii A 5 F 10 15 K B 3 G 11 L16 C 2 13 H D 4 O 9 1 I M 7 12 E P 8 14 J N 6 Location of Muscles Location Involuntary Muscles Diaphragm Digestive organs Arrector pili Arrector Heart Urinary bladder Muscles around blood vessels Muscle Tissue Anatomy Muscle bundle of muscle bundle fibers – fascicle fibers M u s c l e T I s s u e Muscles are made up of bundles of muscle fibers, called fascicles Fascicle is a bundle of muscle fibers A muscle fiber is a muscle cell….made up of many small myofibrils Myofibrils contain filaments Two types of protein filaments A n a t o m y Filaments Muscle Fibers Myofibrils Muscle Fascicle Myofibril Thin Filaments Thin Contain two types of Contain protein filaments protein Actin- thin protein filaments Myosin- thick protein filaments Z disc- point of discanchor of actin anchor SarcomereSarcomerefunctional unit of a myofibril, region between Z discs, Sarcomere Sarcomere Sarcomere Z Disc Thick Filaments Myosin Molecule Actin Molecule Muscle Tissue Anatomy What parts do you What remember? remember? 1. Muscle 2. Fascicle 2. (bundle of fibers) 3. Muscle fiber 3. (muscle cell) 4. Myofibrils 1 D 2 C 3 B A 4 Muscle Tissue Anatomy Continued What parts do you remember?....continued F Actin C Muscle Muscle cell Actin Myofibrils D Fascicle B Fascicle A Myosin G E Filaments Filaments B Sarcomere H C A Muscle Muscle Z Disc I Myofibril H D E I G F Mechanics of a Muscle Contraction Contraction What stimulates a muscle to What contract? contract? Your nervous system What cells are involved? Muscle cells and a motor neuron Motor neuron sends Motor impulse to muscle cells impulse One neuron will form One synapses with many muscle cells muscle What is this called? A A motor unit Let’s take a look under Let’s the microscope.… the motor unit Mechanics of a Muscle Contraction Contraction Where does stimulation occur? Neuromuscular junction How do motor neurons How communicate with muscle cells? muscle Neurotransmitters (typically acetylcholine) carry impulse signal across the gap What happens when a What muscle cell is stimulated? muscle Calcium ions are released into the muscle cell Myofibrils are surrounded by calciumcontaining sarcoplasmic reticulum. Neurotransmitters Mechanics of a Muscle Contraction Contraction What do calcium ions do? Cause interaction between actin and myosin How do actin and myosin interact? Actin filaments slide over the myosin filaments. What model explains this? Sliding Filament Model Mechanics of a Muscle Contraction Contraction What causes actin to slide over What myosin? myosin? The head of myosin connects The to actin and pivots. to What is this connection called? cross-bridge cross-bridge The binding of the myosin The heads throughout the sarcomere occur asynchronously… asynchronously… some myosin heads are some binding while other heads are releasing the actin filaments. This process must be This performed repeatedly during a single muscle contraction so that the muscle is able to generate a smooth force generate Mechanics of a Muscle Contraction Contraction What provides the energy to swivel the head of What ATP myosin? _____ myosin? ATP How exactly does the sliding filament model work? In the sliding filament model of muscle contraction, the (thin) actin filaments [red] (that are attached to the Z-line) slide (are actually pulled) inward along the (thick) myosin filaments [blue], and the sarcomere (measured from one Z line to the next) is shortened. Hey, folks, this thing will run much smoother if you reload it after it runs through once!! http://3dotstudio.com/zz.html http://3dotstudio.com/zz.html Mechanics of a Muscle Contraction Contraction When each sarcomere becomes shorter it When causes each myofibril to become shorter. causes When each When myofibril becomes myofibril shorter it causes shorter the muscle fibers to become shorter to When each When muscle fiber shortens the Sarcomere Sarcomere overall muscle contracts. contracts. Control of a Muscle Contraction Contraction How long does a muscle cell How remain contracted? remain Until the release of acetylcholine stops. How strongly does a muscle fiber contract? To it’s fullest extent. All-or-none response So what controls the So strength of a contraction? strength Number of muscle cells recruited To get a stronger contraction, more To cells are stimulated cells A single cell can’t contract harder A Closer Look at Muscle Contraction Closer “hot” guy Muscle Fiber Deltoid Deltoid muscle muscle Myofibril Actin sarcomere Myosin Macroscopic Structure of Muscle Tendon _________- attaches _________muscle to bone muscle Origin _______- attachment _______of muscle to immovable (fixed) bone (anchors muscle) bone ________- attachment Insertion ________to bone that moves when muscle contracts when _____- bulging middle Belly _____part of the muscle part Belly of Biceps Biceps Muscle Movement Muscle Muscles originate on a _____bone in our body, Muscles fixed cross over a ______, and insert onto a moving ______ joint bone. It is important to understand that all muscles It move from the ________ point insertion going toward the __________ origination point. It is because of the placement It of the muscles that we can move. move. Muscle Movement Muscle Tendons Tendons attach _________ to bone muscle are inelastic are don’t stretch when the force of don’t the muscle acts on them When muscle contracts, When it pulls on the _______ bone it Individual muscles can Individual one only ____ in ____ direction only pull Muscles work in Muscles opposing ______ opposing pairs Muscle Movement Muscle ______- Muscle that bends the joint when Flexor contracted. contracted. Extensor Muscle that straightens the joint ________when contracted. when Contracted __________ muscle iis short, firm, tight s and thicker around. and Relaxed muscle is _______ _______ stretched, long, loose and thinner around. and Muscle Movement Muscle When the biceps in the arm contracts the triceps When biceps relaxes ________ causing ________ of the arm. ________ bending bending contracts When the triceps in the arm _________ the biceps When triceps biceps relaxes causing straightening of the arm. ____________ relaxes _Pairs of muscles are _____ ______ needed because the only active movement _________ of a muscle is to contract to lengthen it _______, must be _________ by stretched the action of an muscle opposing _______. I am am getting motion sicknes sicknes s Muscle Movement Muscle Warning: This illusion Warning: The muscles, bones, and ligaments work t canogether to control body motion. very can make you feel dizzy, especially if you are prone to motion are sickness sickness Muscles In Action Muscles HYPERMUSCLE: MUSCLES IN ACTION Click above to get to this multimedia interactive HTML Click document which will help you learn the muscle actions of the human body. Muscle + Bone Interaction Muscle Let’s review the structures involved in Let’s movement at a joint. B C F A D C G E D C B F B F Ligament Tendon Cartilage Body (Belly) Origin Insertion Contracted muscle Relaxed muscle Flexor Extensor ? ? ? ? ? ? ? ? ? ( ? ? ? , ? 11 ? ) the extensor in the movement of the forearm ? ? ? ? ? ? ? ? (biceps), ? ? (extensor), ? ? ? (opposing muscles) ????( ????????) Muscle Disorders Muscle Sprain A sprain is a wrenching, twisting or stretching injury to a ligament. Sprains often affect the Sprains ankles, knees, or wrists. Result in pain, swelling, redness, bruising, and Result difficulty using injured joint. difficulty Muscle Disorders Muscle Strain Strain A strain is an injury to a muscle or strain tendon, and is often caused by overuse, force, or stretching. overuse, Injured area Injured experiences: pain and pain soreness soreness swelling swelling warmth, bruising, warmth, or redness difficulty using or difficulty moving the injured area in a normal manner Muscle Disorders Muscle Muscle Ruptures There are three degrees of muscle ruptures There A muscle tear may be partial or complete and caused either by muscle a direct blow or by overexertion. direct A first-degree strain involves less than 5 percent of the muscle. A second-degree tear is a greater rupture that stops short of a second-degree complete tear. complete mild pain and not much loss of strength or range of motion. Mild tears referred to as pulled muscles. Any contraction of the torn muscle will cause pain. Any There may be a defect of the muscle - a bump or an indentation There at the site of the most pain. You should be able to partially contract the muscle, but not without You pain pain A third-degree rupture is a complete tear across the width of third-degree the muscle the You will be unable to contract the muscle. You This is what happens when someone suddenly drops while This sprinting. The torn end of the muscle may ball up and form a large lump The under the skin, and a great deal of internal bleeding occurs. Severely torn muscles may require surgery to heal properly. Muscle Disorders Muscle Muscle Pull Muscle Muscle Tear Muscle pull- very slight tear Chronic tear- gradual onset of pain Acute tear- sudden dramatic pain Acute Muscle Muscle Tears Tears Muscle Disorders Muscle Shin splints Shin splints is pain Shin resulting from damage to the muscles along the shin. the Pain is felt in different areas, depending on which muscles are affected. Shin splints represent an "overuse injury" and occur most commonly in runners. Muscle Disorders Muscle Treatment for Muscle Injuries R.I.C.E. Rest: Stop all activities which cause pain. cause Ice: Helps reduce swelling. Never ice more than 10-15 min. at a time. Protect the skin. Compression: Wrap the strained area to reduce swelling. Elevation: Keep the strained area as close to the level of the heart as is conveniently possible to keep blood from pooling in the injured area. from Muscle Disorders Muscle Spasms Cramps Muscle spasm- when A muscle (or even a few Muscle fibers of a muscle) involuntarily contract Muscle cramp- involuntarily + forcibly Muscle contracted muscle that does not relax contracted A forceful + sustained spasm Nick named charley horse Muscle feels tied up in knots Can last anywhere from a few Can seconds to a quarter of an hour Caused by strain or injury Muscle Disorders Muscle Tetanus Tetanus Tetanus is a preventable disease through vaccination Tetanus Caused by bacteria that enters the body Caused through the skin Found in soil, dust and manure Found Toxin bacteria produces interferes with nerve Toxin transmission to your muscles and causes them to seize up in painful spasms. them Tetanus typically starts in the jaw and muscles Tetanus of the face, quickly spreading to the arms and legs. “Lockjaw” Difficulty swallowing Difficulty Intestines often seize up Bladder fails to empty Asphyxiation Asphyxiation Cardiac arrest Cardiac Muscle Disorders Muscle Anabolic Steroids Anabolic Produced naturally by the body to support such functions as Produced fighting stress and promoting growth and development fighting Referred to as roids, juice, hype, weight trainers, gym candy, Referred arnolds, stackers, or pumpers arnolds, People use steroid pills, gels, creams, or injections to improve their People sports performance or the way they look. Anabolic steroids cause many different types of problems types of problems types premature balding or hair loss premature dizziness dizziness mood swings problems sleeping problems nausea and vomiting nausea high blood pressure aching joints aching urinary problems urinary shortening of final adult height shortening increased risk of heart disease, stroke, and some cancers stroke, Muscle Disorders Muscle Cerebral Palsey Cerebral palsy is a group of disorders that affect a Cerebral person's ability to move and to maintain balance and person's posture. The disorders appear in the first few years of life, and first usually don’t get worse over time. People with cerebral palsy People may have difficulty walking. They may also have trouble with tasks such as writing or using scissors. Some people with cerebral palsy have other Some medical conditions, including seizure disorders or mental impairment. Cerebral palsy happens when the areas of Cerebral the brain that control movement and posture do not develop correctly or get damaged. do Muscle Disorders Muscle Muscular Dystrophy Muscular Dystrophy- most well known of most hereditary diseases hereditary A genetic condition that describes over 20 genetic genetic and hereditary muscle diseases. genetic Characterized by progressive skeletal muscle Characterized weakness, defects in muscle proteins, and the death of muscle cells and tissue. death In some cases, cardiac and smooth muscles In are affected. Principal symptoms: Principal Progressive Muscular Wasting (weakness) Progressive Poor Balance and Frequent Falls requent Walking Difficulty + Waddling Gait Walking Limited Range of Movement Limited Scoliosis (curvature of the spine) Scoliosis Inability to Walk Inability Muscle Atrophy and Drooping Eyelids Muscle Disorders Muscle Myasthenia Gravis Myasthenia Myasthenia gravis- chronic autoimmune neuromuscular disease characterized by varying degrees of weakness of the skeletal muscles muscles Caused by a defect in the transmission of Caused nerve impulses at the neuromuscular junction nerve Antibodies (produced by the body's own Antibodies immune system) block, alter, or destroy the receptors for acetylcholine at the neuromuscular junction which prevents the muscle contraction from occurring. The characteristic symptom of myasthenia gravis is fatigability, which The means that a muscle that is used repeatedly starts to become weak. The symptoms usually start in the face and spread to the other parts of The the body as the disease progresses. Certain muscles such as those that control eye and eyelid movement, Certain facial expression, chewing, talking, and swallowing are often involved facial The muscles that control breathing and neck and limb movements may The also be affected. Patients initially complain of drooping eye lids that get worst as the Patients day goes on; they develop double vision, difficulty talking, and difficulty chewing. Muscle weakness increases during periods of activity and improves Muscle after periods of rest. Muscle Disorders Muscle Polio Polio Poliomyelitis, often called polio is an acute often polio viral infectious disease which is spread from person-to-person via the fecal-oral route. person-to-person The majority of polio infections are asymptomatic. The In about 1% of cases the virus enters the (CNS) via the In blood stream. Within the CNS, poliovirus infects and Within destroys motor neurons. The destruction of The Old Polio motor neurons Asymmetric atrophy causes muscle & weakness weakness and Atrophic right leg flaccid paralysis flaccid (arrow) in patient Vaccination created Vaccination with paralytic polio 70 by Jonas Salk in years in past 1955 has eliminated the disease the ...
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