Pectoral (Shoulder) Girdle • Two pectoral girdle. • Each girdle attach the upper limbs to axial skeleton. • Consist of two bones: – Clavical anteriorly. – Scapula posteriorly. Upper Limb • Consist of: – Humerus – Ulna – radius – 8- carpals – 5- metacarpals – 14 phalanges 1 Carpals • 8 carpals arranged in two transverse rows; 4 bones each Pelvic (Hip) Girdle • Two hip bones • Bony pelvis: – pubic symphysis, sacrum, hip bones • Hip bone consist of 3 bones – Ilium: Superior – Pubis: Inferior and anterior – Ischium: inferior and posterior 2 Lower Limb • Each lower limb consist of: 1. Femur 2. Patella 3. Tibia 4. fibula 5. 7 tarsals 6. 5 metatarsals 7. 14 phalanges Tarsal Bones • Calcaneus: • Cuboid bone • Navicular • cuneiform bones • Talus bone • Intertarsal joints: 3 Bone Fracture • Simple or closed fracture: – Does not break the skin • Open (compound) fracture: – Broken ends protrude through the skin Exercise and Bone Tissue • Increase mineral salts deposition and production of collagen fibers – athletes bones are thicker and stronger • Without mechanical stress – Affect mineralization and decreased number of collagen fibers 4 Muscle System Muscles • Come from the Latin word mus ( little mouse) because flexing muscles look like mice scurrying beneath the skin • Muscle characteristics – All muscles contract; essential for all body movements – All have the prefixes- myo-, mys- , or sarco- Three types of Muscle Tissue – Skeletal muscles – Smooth Muscles – Cardiac muscle 5 Function of Muscle Tissue 1. Producing body movement: – Walking, nodding …etc. 2. Stabilizing body positions – Postural muscle - neck muscle…etc. – Stabilizing joints - maintain body position. 3. Storing and moving substances within the body: – Intestine, Heart, Arteries 4. Generating heat: – Contraction heat thermogenesis. Neuromuscular Junction • The region of contact between the somatic motor neuron and the membrane (sarcolemma) of a muscle cell 6 Muscle Fatigue • Inability of the muscle to contract even though it is still being stimulated – Lack oxygen lactic acid accumulate – Decrease ATP supply • Is a small amount of tension in the muscle Muscle tone due to weak, involuntary contraction • Does not produced movement • To sustain muscle tone, small groups of motor units are alternately active and inactive in a shifting pattern ( GI, back, neck, vessels • In flaccid muscle, the tone is lost 7 Coordination with a muscle groups • Opposing: – Prime mover (agonists): causing a particular movement. – Antagonist: opposes or reverse a movement – If the prime mover active, the antagonist relaxes • Synergists: – Help the prime movers Effect of exercise on muscle • Exercise – increases muscle size and strength – immobilization leads to muscle weakness • Aerobic exercise – Increases blood supply to the muscle – Increase mitochondria and store more oxygen – Improve digestion – Enhance neuromuscular coordination • Resistance exercise: – Increase muscle size 8 Regeneration of muscle tissue is • Hypertrophy – enlargement of existing cells • Hyperplasia: – increase in the number of fibers (uterus) • Fibrosis: – replacement of muscle fibers by fibrous scar tissue Gliding • Flat bone surfaces move back-and –forth and side-to-side • No significant alteration of the angle between the bones • Limited to range 9 Flexion • Decreases the angle between articulating bones Extension • Opposite of flexion • Increases the angle between articulating bones • Hyperextension: – extension greater than 180° 10 Lateral flexion • Involves intervertebral joints Extension of the shoulder 11 Hyperextension moves a joint beyond the usual extended angle • Abduction: – Movement away from the midline • Adduction – Movement toward the midline • Circumduction: – The continuous sequence of flexion, abduction, extension, adduction. – Example moving the humerus in a circle at the shoulder joint 12 • Rotation: – The bone revolves around its longitudinal axis Special movement • Elevation: – upward movement of a part of the body • Depression: – downward movement of a part of the body • Protraction: – movement of a part of the body anteriorly in the transverse plane • Retraction: – movement of protracted part back to the anatomical position. 13 Special movements of the foot • Inversion: – movement of the soles medially at the intertarsal joints – the soles face each other • Eversion: – Movement of the soles laterally at the intertarsal joints – The soles away from each other • Dorsiflexion: – Bending the foot and ankle in the direction of the dorsum – stand on your heels • Plantar flexion: – Bending the foot and ankle and the direction of the planter surface – Stand on your toes Special movements • Supination: – a movement of the forearm at the proximal and distal radioulnar joint – the palm is turned anteriorly or superiorly i.e. anatomical position • Pronation – movement of the forearm at the proximal and distal radioulnar joints – the distal end of the radius crosses over the distal end of the ulna – The palms turn posteriorly or inferiorly • Opposition: – The movement of the thumb of the carpometacarpal joint – The thumb moves across the palm to touch the tip of the fingers on the same hand i.e. the ability to grasp 14 Nervous System Structural Classification • Central nervous system (CNS) – Occupies the dorsal body cavity; Brain and spinal cord • Peripheral nervous system (PNS) – Cranial nerve and its branches – Spinal nerves and its branches – Ganglia (cell bodies outside the central nervous system) – Sensory receptors 15 Functional Classification of Peripheral Nervous System (PNS) • Somatic nervous system – Sensory neurons carry information from somatic receptors to the central nervous system (CNS) – Motor neurons carry impulses from CNS to skeletal muscles • Autonomic nervous system – Sensory neurons carry information from receptors in the visceral organs to CNS – Motor neurons carry impulses from CNS to involuntary muscles and glands Histology of Nervous System Two cell types: 1. Supporting cell (Also called Neurogliae or glia; glue cells) – Support, nourish and protect neurons. – Do not generate or propagate action potential – Can Multiply and divide (most brain tumors are glioma) – Six types • 4 in the CNS: Astrocytes, oligodendrocytes, Microglia, epindymal cells • 2 in the PNS: Schwann cells , and Satellite cells 2. Neurons: – Transmit nerve impulses 16 Neurons (nerve cell) • consist of : 1. cell body contains Nucleus, Cytoplasm, Organelles (except centrioles), Nissl bodies (prominent clusters of rough ER, Neurofibrils ( maintain cell shape) 2. dendrites contains Short, and highly branched. The receiving portion of a neuron 3. axon: long branch Axons – Only one axon per neuron – Transmit nerve impulses away from the cell body – Axon terminals are fine processes at the end of the axon and contain vesicles that store the neurotransmitters 17 • Myelin sheath: – Multilayer lipid and protein covers the axons – Electrically insulates axons which increase the speed of nerve impulse – node of ranvier • Nuclei: cell bodies in the CNS • Ganglia: small collections of cell bodies found in PNS • Tracts: Bundle of nerve fibers running through CNS • Nerves: Bundle of nerve fibers in the PNS • White matter: aggregations of myelinated fibers (tracts) • Gray matter: mostly unmyelinated fibers and cell bodies 18 Characteristics of neurons • Long-lived – Generally last a life time • Amitotic – neurons do not divide • High metabolic rate – This means high oxygen demand and lots of mitochondria – Neurons require glucose. Integration 3 1 Stimulus 2 Sensory neuron center Skin 4 Motor neuron Interneuron Receptor 5 Effector • Reflexes are rapid, predictable, involuntarily responses to stimuli • Types – Autonomic reflexes: • Regulate smooth muscles, heart, glands • Example: pupillary reflex – Somatic reflexes • All reflexes that stimulate skeletal muscles • Reflex arc elements: – Sensory receptor ( reacts to stimuli), Sensory (afferent) neuron, CNS integration center, Motor (efferent) neuron, Effector organ 19 Chemical Synapse Transmits a signal as Follows: • Nerve impulse reach the synaptic end bulb of presynaptic axon • The vesicles release neurotransmitter into the synaptic cleft • neurotransmitter attach to the receptors in the postsynaptic neurons which result in depolarization. Central Nervous System (CNS) • Brain components – Cerebral hemispheres – Diencephalons – Brain stem – cerebellum 20 Cerebral Hemispheres • Paired, most superior part of the brain • Encloses most of the brain stem • the elevated ridges of the surface called gyri separated by shallow grooves called sulci • Fissures: – deeper groove separate large regions of the brain – cerebral hemispheres separated by longitudinal fissure • Fissures and sulci divide the hemispheres into lobes • Left hemisphere controls right side of the body and right hemisphere controls the left side of the body Lobes of the cerebral hemisphere • Frontal – Motor control area – Intellectual area • Parietal – General sensation • Temporal – For hearing and smell • Occipital – Visual area • Insula – For taste 21 Somatic sensory area • located in the parietal lobe • The left side receives impulses from the right side and vice versa Primary Motor area • Allow us consciously to move our skeletal muscles • Located in the frontal lobe • The left side receives impulses from the right side and vice versa 22 Broca’s area • Specialized area involved in our ability to speak • Found at the base of precentral gyrus • Located in only one cerebral hemisphere (usually left) • Damage to