1 / 55

Chapter 10

Chapter 10. Muscle Tissue Lecture Outline. INTRODUCTION. Muscles: Make up 40-50% of the body weight Contribute to homeostasis The scientific study of muscles is known as myology. OVERVIEW OF MUSCLE TISSUE. There are 3 types of muscle tissue: Skeletal Cardiac Smooth.

myles-barrett
Download Presentation

Chapter 10

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Chapter 10 Muscle Tissue Lecture Outline

  2. INTRODUCTION • Muscles: • Make up 40-50% of the body weight • Contribute to homeostasis • The scientific study of muscles is known as myology.

  3. OVERVIEW OF MUSCLE TISSUE • There are 3 types of muscle tissue: • Skeletal • Cardiac • Smooth Principles of Human Anatomy and Physiology, 11e

  4. Skeletal Muscle Tissue • Skeletal muscle • Move the bones of the skeleton • Attaches to the bone or the skin • It is striated: alternating bands of dark and light • Voluntary control of contraction & relaxation Principles of Human Anatomy and Physiology, 11e

  5. Cardiac Muscle Tissue • Cardiac muscle • Forms the wall of the heart • Striated in appearance • Control is involuntary • An internal pacemaker controls the heartbeat • This rhythm is called autorhymicity and is controlled by hormones, nerve impulses, and neurotransmitters Principles of Human Anatomy and Physiology, 11e

  6. Smooth Muscle Tissue • Smooth muscle • Located in the walls of blood vessels, airways, and organs; also attached to hair follicles • Nonstriated in appearance (smooth) • Involuntary control • Propels food through your gastrointestinal tract Principles of Human Anatomy and Physiology, 11e

  7. Functions of Muscle Tissue • Producing body movements • Stabilizing body positions • Regulating organ volumes • bands of smooth muscle called sphincters • Movement of substances within the body • blood, lymph, urine, air, food and fluids, sperm • Producing heat • involuntary contractions of skeletal muscle (shivering) produce heat through thermogenesis Principles of Human Anatomy and Physiology, 11e

  8. Properties of Muscle Tissue • Excitability • respond to chemicals released from nerve cells • Conductivity • ability to propagate electrical signals over membrane • Contractility • ability to shorten and generate force • Extensibility • ability to be stretched without damaging the tissue • Elasticity • ability to return to original shape after being stretched Principles of Human Anatomy and Physiology, 11e

  9. Muscles you need to know • Sternocleidomastoid (neck) • Trapezius (shoulder blade) Principles of Human Anatomy and Physiology, 11e

  10. Muscles you need to know • Deltoid (shoulders) Pectoralis major (upper and lower chest) Principles of Human Anatomy and Physiology, 11e

  11. Muscles you need to know • Biceps brachii • Brachialis • Brachioradialis • (humerus to radius) Principles of Human Anatomy and Physiology, 11e

  12. Muscles you need to know • Latissimus dorsi (middle back) • Rectus abdominis (6-pack abs) • External oblique (side abs) Principles of Human Anatomy and Physiology, 11e

  13. Muscles you need to know • The 4 muscles of the quadricep (thigh) • Vastus lateralis • Vastus intermedius • Vastus medialis • Rectus Femoris Principles of Human Anatomy and Physiology, 11e

  14. Muscles you need to know • Triceps brachii (back of the arms) Principles of Human Anatomy and Physiology, 11e

  15. Muscles you need to know • Infraspinatus (scapula) • Teres minor • (attaches scapula to humerus) • Teres major • (attaches humerus to ribs) Principles of Human Anatomy and Physiology, 11e

  16. Muscles you need to know • Gluteus maximus (butt) • Semitendinosus (hamstring) • Biceps femoris (hamstring) Principles of Human Anatomy and Physiology, 11e

  17. Muscle Poster Gallery Walk • Due Friday: gallery walk and note taking on: • Each group will create a poster that includes: • 2 detailed, colored drawings of your muscle group • Identify, label, and explain the function of 10 individual muscles • List one interesting fact/characteristic of your muscles • 1 (Erika): Face/Head (338-339) • 2 (Celine): Upper Arm/Shoulder (361, 364-5) • 3 (Jeffrey): Forearm, wrist, hands (368, 372-3, 376) • 4 (Rachelle): Vertebral column (381-2) • 5 (Jenny): Upper leg, femur (385-387) • 6 (Victoria): Lower leg, foot, toes (393-4, 397) • 7 (Marco): Thorax, abdomen (352, 354) • 8 (Ashley): The Whole Body (334-335) Principles of Human Anatomy and Physiology, 11e

  18. SKELETAL MUSCLE TISSUE • Each skeletal muscle is a separate organ composed of cells called muscle fibers. Principles of Human Anatomy and Physiology, 11e

  19. Connective Tissue Components • Connective tissue surrounds and protects muscular fibers (cells) • A tendon is a cord of dense connective tissue that attaches a muscle to the bone • An aponeurosisis a tendon that extends as a broad, flat layer. Principles of Human Anatomy and Physiology, 11e

  20. Nerve and Blood Supply • Each skeletal muscle is supplied by a nerve, artery and two veins. • The nerve directs muscle movement and the artery supplies blood to the muscle. Principles of Human Anatomy and Physiology, 11e

  21. Muscle Fibers • Muscle cells are long, cylindrical & multinucleated • A muscle fiber averages 4 inches long and can grow up to 12 inches. Principles of Human Anatomy and Physiology, 11e

  22. Parts of a Muscle Cell • Skeletal muscle consists of fibers (cells) covered by a sarcolemma, the plasma membrane. • Transverse (T) tubules are tunnels that allow fluid to enter and exit cells

  23. Principles of Human Anatomy and Physiology, 11e

  24. Parts of a Muscle Cell • Sarcoplasmis the muscle cell cytoplasm and contains a large amount of glycogen for energy production and myoglobin for oxygen storage. • Myofibrils allow the muscles to contract • Filaments are small structures that are also involved in muscle contraction

  25. Principles of Human Anatomy and Physiology, 11e

  26. The Proteins of Muscle • Myofibrils (the part that contracts) are built of 3 kinds of protein • contractile proteins which generate force (myosin and actin) • Regulatory proteins which receive signals (troponin and tropomyosin) • Structural proteins which give elasticity to the muscle

  27. Sliding Filament Mechanism Of Contraction • Thin and thick filament slide past each other • During muscle contraction, the filaments slide towards each other and the muscle is shortened • The muscle then relaxes and returns to normal length. Principles of Human Anatomy and Physiology, 11e

  28. Neuromuscular Junction (NMJ) or Synapse • NMJ = neuromuscular junction: the space between a neuron and a skeletal muscle-sends nerve impulses into the muscle.

  29. Muscle MetabolismProduction of ATP in Muscle Fibers • Muscle use ATP at a great rate when active • 3 sources of ATP production within muscle • creatine phosphate (synthesized from food) can power muscles for 15 seconds. • anaerobic cellular respiration (making ATP without oxygen, when exercising) can power muscles for 30 seconds. • aerobic cellular respiration (makes the most ATP) can power muscles for longer periods of time. Principles of Human Anatomy and Physiology, 11e

  30. Muscle Fatigue • Inability to contract after prolonged activity • Why do your muscles get tired? • central fatigue is feeling of tiredness and a desire to stop (protective mechanism) • insufficient release of neurotransmitters from motor neurons • depletion of creatine phosphate • decline of Ca+2 within the sarcoplasm • insufficient oxygen or glycogen • buildup of lactic acid and ADP (anaerobic muscle activity) Principles of Human Anatomy and Physiology, 11e

  31. Twitch contraction • A twitch contraction is a brief contraction of all the muscle fibers in a motor unit in response to a single action potential (one involuntary muscle movement). • A myogram is a graph of a twitch contraction

  32. Myogram of a Twitch Contraction Principles of Human Anatomy and Physiology, 11e

  33. Motor Unit Recruitment • Motor units in a whole muscle fire independently, at different times. • Produces smooth muscular contraction • not series of jerky movements Principles of Human Anatomy and Physiology, 11e

  34. Isotonic and Isometric Contraction • Isotonic Contractions • Involves muscle movement • Isometric Contraction = no movement occurs • tension is generated but muscles do not move • maintaining posture & supports objects in a fixed position Principles of Human Anatomy and Physiology, 11e

  35. Types of Muscle Fibers • Slow oxidative (slow-twitch) • red in color (lots of mitochondria, myoglobin & blood vessels) • prolonged, sustained contractions for maintaining posture • Oxidative-glycolytic (fast-twitch A) • red in color (lots of mitochondria, myoglobin & blood vessels) • split ATP at very fast rate; used for walking and sprinting • Fast glycolytic (fast-twitch B) • white in color (few mitochondria & BV, low myoglobin) • anaerobic movements for short duration; used for weight-lifting Principles of Human Anatomy and Physiology, 11e

  36. Things that Interfere with the NMJ • Botulinum Toxin (Botox) blocks release of neurotransmitter at the NMJ so muscle contraction can not occur • bacteria found in improperly canned food • death occurs from paralysis of the diaphragm • Relaxes facial muscles to reduce appearance of wrinkles • Curare (plant poison used on poison arrows) • causes muscle paralysis • used to relax muscle during surgery

  37. Anabolic Steroids • Similar to testosterone • Increases muscle size, strength, and endurance • Side Effects: • liver cancer • kidney damage • heart disease • mood swings • facial hair & voice deepening in females • atrophy of testicles & baldness in males Principles of Human Anatomy and Physiology, 11e

  38. CARDIAC MUSCLE TISSUE - Overview • Cardiac muscle tissue is found only in the heart wall • Its fibers are arranged similarly to skeletal muscle fibers. • Cardiac muscle contractions last longer than the skeletal muscle twitch. • Cardiac muscle fibers contract when stimulated by their own autorhythmic fibers. • On average, contract 75 times per minute Principles of Human Anatomy and Physiology, 11e

  39. SMOOTH MUSCLE • Smooth muscle tissue is nonstriated and involuntary. Principles of Human Anatomy and Physiology, 11e

  40. Two Types of Smooth Muscle • Visceral (single-unit) • in the walls of small blood vessels • Multiunit • found in large arteries, large airways, and attached to hair follicles Principles of Human Anatomy and Physiology, 11e

  41. Regeneration of Muscle • Skeletal muscle fibers cannot divide after 1st year • Cardiac muscle fibers cannot divide or regenerate • Smooth muscle fibers CAN regenerate • new fibers can form from stem cells in blood vessel walls Principles of Human Anatomy and Physiology, 11e

  42. Aging and Muscle Tissue • Skeletal muscle starts to be replaced by fat beginning at 30 • “use it or lose it”: do free weight exercises • Results in slowing of reflexes & decrease in maximal strength Principles of Human Anatomy and Physiology, 11e

  43. Diseases and Disorders: Myasthenia Gravis • Progressive autoimmune disorder that blocks receptors at the neuromuscular junction • More common in women 20 to 40 with possible line to thymus gland tumors • Begins with double vision & swallowing difficulties & progresses to paralysis of respiratory muscles Principles of Human Anatomy and Physiology, 11e

  44. Muscular Dystrophies • Inherited, muscle-destroying diseases • Sarcolemma tears during muscle contraction • Mutated gene is on X chromosome so problem is with males almost exclusively • Appears by age 5 in males and by 12 may be unable to walk Principles of Human Anatomy and Physiology, 11e

  45. Fibromyalgia • Fibromyalgia is a painful disorder that affects people aged 25-50, 15 times more common in women (genetic) • Without pressure, muscles are painful, tender, and stiff • Fatigue, poor sleep, headaches, depression results • Treatment includes exercise, stress reduction, heat, massage, pain meds

  46. Abnormal Contractions • Spasm = involuntary contraction of single muscle • Cramp = a painful spasm • Tic = involuntary twitching of muscles normally under voluntary control--eyelid or facial muscles • Tremor = rhythmic, involuntary contraction of opposing muscle groups • Fasciculation = involuntary, brief twitch of a motor unit visible under the skin Principles of Human Anatomy and Physiology, 11e

  47. Atrophy and Hypertrophy • Atrophy • wasting away of muscles • caused by disuse (disuse atrophy) or severing of the nerve supply (denervation atrophy) • Hypertrophy • increase in the diameter of muscle fibers • resulting from very forceful, repetitive muscular activity Principles of Human Anatomy and Physiology, 11e

  48. Plantar Fascitis • Plantar fascitis, or painful heel syndrome, is swelling and inflammation due to chronic irritation of the heel bone (walking, jogging, wearing high heels) • Treated by ice, heat, stretching, weight loss, prosthetics, steroids, or surgery Principles of Human Anatomy and Physiology, 11e

  49. Shin Splints • Shin splints refers to pain along the tibia, caused by stress fractures due to vigorous activity • Treated with ice, rest, and muscle strengthening activities

  50. Pulled Hamstrings • A strain or tear of the hamstring muscles – a common sports injury • Accompanied by bruising, tearing, rupture of blood vessels, and pain Principles of Human Anatomy and Physiology, 11e

More Related