Muscular System. Muscle Functions Movement Posture Protection Body Heat - Endothermic

Transcription

1 Muscular System Muscle Tissue Types Smooth Muscle - Nonstriated and Involuntary Cardiac Muscle - Striated and Involuntary Skeletal Muscle Striated and Voluntary Muscle Functions Movement Posture Protection Body Heat - Endothermic

2 Fig. 8.01

3 Figure 6.1 Connective tissue wrappings of skeletal muscle. Blood vessel Muscle fiber (cell) Perimysium Epimysium Fascicle (wrapped by perimysium) Tendon Endomysium (between fibers) Bone

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7 Figure 6.3a Anatomy of a skeletal muscle fiber (cell). (a) Segment of a muscle fiber. Sarcolemma Myofibril Dark (A) band Light (I) band Nucleus (a) Segment of a muscle fiber (cell)

8 Figure 6.3b Anatomy of a skeletal muscle fiber (cell). (b) Myofibril or fibril. Z disc H zone Z disc Thin (actin) filament Thick (myosin) filament (b) Myofibril or fibril (complex organelle composed of bundles of myofilaments) I band A band Sarcomere I band M line

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15 Figure 6.5b

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17 Figure 6.3c Anatomy of a skeletal muscle fiber (cell). (c) Sarcomere. I band Sarcomere I band Thin (actin) filament Z disc M line Z disc Thick (myosin) filament (c) Sarcomere (segment of a myofibril)

18 Figure 6.3d Anatomy of a skeletal muscle fiber (cell). (d) Myofilament structure. Thick filament Bare zone Thin filament (d) Myofilament structure (within one sarcomere)

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20 Sliding Filament Theory e=true&persist_safety_mode=1&safe=active 2:59 e=related&safety_mode=true&persist_safety_mode=1&saf e=active 1:00 mode=true&persist_safety_mode=1&safe=active 4:00

21 IxeEHBFdU&safety_mode=true&persist_safety_mode=1&safe=active

22 Figure 6.4a Motor units. (a) Portions of two motor units are shown. Spinal cord Axon terminals at neuromuscular junctions Motor unit 1 Motor unit 2 Nerve Motor neuron cell bodies Axon of motor neuron Muscle Muscle fibers (a)

23 Figure 6.5a The neuromuscular junction. (a) Axon terminal of a motor neuron forming a neuromuscular junction with a muscle fiber. Myelinated axon of motor neuron Action potential Axon terminal Sarcolemma of the muscle fiber Nucleus (a)

24 Figure 6.5b The neuromuscular junction. (b) The axon terminal contains vesicles filled with the neurotransmitter acetylcholine (ACh), which is released when the nerve impulse reaches the axon terminal. Axon terminal of a motor neuron Mitochondrion Synaptic cleft T tubule Invagination of the sarcolemma at neuromuscular junction Part of a myofibril Synaptic vesicle containing ACh Ca 2+ Action potential (b)

25 Neuromuscular Junction mode=true&persist_safety_mo de=1&safe=active 1: /animation function_of_the_neuromuscular_ju nction quiz_1_.html 1:30 ASKJJoSY&feature=related 8:51 endscreen&v=9ff6ukvdgee&nr=1&s afety_mode=true&persist_safety_mode =1&safe=active 1:30

26 Figure 6.5c The neuromuscular junction. (c) Acetylcholine diffuses across the synaptic cleft and attaches to ACh receptors on the sarcolemma, initiating changes in the electrical condition of the sarcolemma. Axon terminal Fusing synaptic vesicle ACh molecules Acetic acid Synaptic cleft Choline K + (c) Na + AChE Binding of Ach to receptor opens Na + /K + channel

27 Figure 6.12 Muscle attachments (origin and insertion). Pg. 199 Muscle contracting Origin Brachialis Tendon Insertion

28 About 600 Skeletal Muscles Muscles Cannot Push Skeletal Muscles work in units (pg Prime Mover (Agonist) Antagonist Synergist Fixators

29 Types of Muscle Contractions Isotonic Belly (Gaster) Isometric

30 Figure 6.15 Superficial muscles of the face and neck. Frontalis Cranial aponeurosis Temporalis Orbicularis oculi Occipitalis Zygomaticus Buccinator Orbicularis oris Masseter Sternocleidomastoid Platysma Trapezius

31 Figure 6.16a Muscles of the anterior trunk, shoulder, and arm. (a) Muscles crossing the shoulder joint, causing movements of the arm. Clavicle Deltoid Sternum Pectoralis major Biceps brachii Brachialis Brachioradialis (a)

32 Figure 6.16b Muscles of the anterior trunk, shoulder, and arm. (b) Muscles of the abdominal wall. Pectoralis major Rectus abdominis Transversus abdominis Internal oblique External oblique Aponeurosis (b)

33 Figure 6.17a Muscles of the posterior neck, trunk, and arm. (a) Superficial muscles. Occipital bone Sternocleidomastoid Trapezius Deltoid Spine of scapula Deltoid (cut) Triceps brachii Latissimus dorsi (a) Humerus Olecranon process of ulna (deep to tendon)

34 Figure 6.17b Muscles of the posterior neck, trunk, and arm. (b) The erector spinae muscles (longissimus, iliocostalis, and spinalis), deep muscles of the back. C 7 T 1 Erector spinae Iliocostalis Longissimus Spinalis (b) Quadratus lumborum

35 Figure 6.19a Pelvic, hip, and thigh muscles of the right side of the body. (a) Posterior view of the hip and thigh muscles. Gluteus medius Gluteus maximus Adductor magnus Iliotibial tract Biceps femoris Semitendinosus Semimembranosus Hamstring group (a) Gastrocnemius

36 Figure 6.19b Pelvic, hip, and thigh muscles of the right side of the body. (b) Diagram showing deep structures of the gluteal region and the proper site for administering an injection into the gluteus medius muscle. Posterior superior iliac spine Iliac crest Safe area in gluteus medius Gluteus maximus Sciatic nerve (b)

37 Quadriceps Figure 6.19c Pelvic, hip, and thigh muscles of the right side of the body. (c) Anterior view of pelvic and thigh muscles. 12th rib Iliac crest 12th thoracic vertebra Iliopsoas Psoas major Iliacus Anterior superior iliac spine Sartorius Rectus femoris Vastus lateralis Vastus medialis (c) 5th lumbar vertebra Adductor group Patella Patellar ligament

38 Figure 6.19d Pelvic, hip, and thigh muscles of the right side of the body. (d) Diagram showing the proper site for administration of an injection into the lateral thigh (vastus lateralis muscle). Vastus lateralis Inguinal ligament Adductor muscles Sartorius (d)

39 Figure 6.20a Superficial muscles of the right leg. (a) Anterior view. Fibularis longus Fibularis brevis Tibialis anterior Extensor digitorum longus Tibia Soleus Fibularis tertius (a)

40 Figure 6.20b Superficial muscles of the right leg. (b) Posterior view. Gastrocnemius Soleus Calcaneal (Achilles) tendon Medial malleolus Lateral malleolus (b)

41 Figure 6.21 Major superficial muscles of the anterior surface of the body. Shoulder Trapezius Deltoid Arm Triceps brachii Biceps brachii Brachialis Forearm Brachioradialis Flexor carpi radialis Pelvis/thigh Iliopsoas Thigh (Quadriceps) Rectus femoris Vastus lateralis Vastus medialis Facial Temporalis Masseter Facial Frontalis Orbicularis oculi Zygomaticus Orbicularis oris Neck Platysma Sternocleidomastoid Thorax Pectoralis minor Pectoralis major Serratus anterior Intercostals Abdomen Rectus abdominis External oblique Internal oblique Transversus abdominis Thigh Sartorius Adductor muscle Gracilis Leg Fibularis longus Extensor digitorum longus Tibialis anterior Leg Gastrocnemius Soleus

42 Figure 6.22 Major superficial muscles of the posterior surface of the body. Neck Occipitalis Sternocleidomastoid Trapezius Arm Triceps brachii Brachialis Forearm Brachioradialis Extensor carpi radialis longus Flexor carpi ulnaris Extensor carpi ulnaris Extensor digitorum Shoulder/Back Deltoid Latissimus dorsi Hip Gluteus medius Gluteus maximus Iliotibial tract Thigh Adductor muscle Hamstrings: Biceps femoris Semitendinosus Semimembranosus Leg Gastrocnemius Soleus Fibularis longus

43 Systems in Sync (1 of 2) Homeostatic Relationships Between the Muscular System and Other Body Systems Endocrine System Growth hormone and androgens influence skeletal muscle strength and mass Lymphatic System/Immunity Physical exercise may enhance or depress immunity depending on its intensity Lymphatic vessels drain leaked tissue fluids; immune system protects muscles from disease Nervous System Facial muscle activity allows emotions to be expressed Nervous system stimulates and regulates muscle activity Respiratory System Muscular exercise increases respiratory capacity Respiratory system provides oxygen and disposes of carbon dioxide Cardiovascular System Skeletal muscle activity increases efficiency of cardiovascular functioning; helps prevent atherosclerosis and causes cardiac hypertrophy Cardiovascular system delivers oxygen and nutrients to muscles; carries away wastes

44 Systems in Sync (2 of 2) Homeostatic Relationships Between the Muscular System and Other Body Systems Digestive System Physical activity increases gastrointestinal mobility when at rest Digestive system provides nutrients needed for muscle health; liver metabolizes lactic acid Urinary System Physical activity promotes normal voiding behavior; skeletal muscle forms the voluntary sphincter of the urethra Urinary system disposes of nitrogenous wastes Reproductive System Skeletal muscle helps support pelvic organs (e.g., uterus in females); assists erection of penis and clitoris Testicular androgen promotes increased skeletal muscle size Integumentary System Muscular exercise enhances circulation to skin and improves skin health; exercise also increases body heat, which the skin helps dissipate Skin protects the muscles by external enclosure Skeletal System Skeletal muscle activity maintains bone health and strength Bones provide levers for muscle activity