Pectoral (Shoulder) Girdle Upper Limb

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 this area causes inability to say words properly

Speech area

• Located at the junction of the temporal lobe and the parietal lobe, and occipital lobe • Allow us to sound words • Only in one hemisphere, usually the left

23 • Higher intellectual reasoning located in the anterior part of the frontal lobe • Language comprehension (word meaning) located in the frontal bone

Diencephalons

• Thalamus: • Hypothalamus • epithalamus

24 • Thalamus – Relay station for sensory impulses passing upward to the sensory cortex

Hypothalamus • Under the thalamus • Connect to pituitary gland • Center of many drives and emotions; thirst, appetite, sex, pain, pleasure (connected to the limbic system) • Plays a role in the regulation of body temperature, water

25 Epithalamus • Epithalamus components – Pineal body • Secret melatonin. – Choroids plexus: • Secret cerebrospinal fluid

Brain stem

• Consist of – Midbrain – Pons – Medulla oblongata

26 • Cerebral aqueduct midbrain travels through the midbrain connecting the third ventricle to the fourth ventricle • Contain Reflex centers, involved in vision and hearing

Pons

• round structure protrudes below the midbrain • Have nuclei involved in breathing

27 Medulla Oblongata

• Most inferior part of the brain stem • Contain centers that control heart rate, blood pressure, breathing, swallowing, vomiting…etc.

cerebellum

• Projects dorsally from under the occipital lobe • Has two hemispheres and convoluted surface • Controls our balance

28 Menings • Three connective tissue covering the brain, from superficial to deep: 1. Dura mater: Leathery, outer most layer covers the brain and continues with spinal dura mater 2. Arachnoid mater: Has extensions span the subarachnoid space and attach to pia mater

Menings 3. Pia mater: clings tightly to brain surface and spinal cord following every fold • Arachnoid villi: protrude through dura mater, absorb CSF • Subarachnoid space: between the arachnoid and pia mater filled with CSF

29 Brain Ventricles

• Lateral ventricles in the cerebral hemispheres • Third ventricle in the diencephalon • Cerebral canal in the midbrain • Fourth ventricle between the pons and cerebellum

Cerebrospinal Fluid • Coroid plexus secret CSF in the ventricles • From lateral ventricles  to third ventricle  cerebral aqueduct  fourth ventricle  central canal of spinal cord and subarachnoid space  arachnoid villi  blood • changing in color, appearance, or composition, indicates disease. • Obstruction of circulation causes hydrocephalus

30 Cranial Nerves

• 12 pairs serve the head and the neck • Only the vagus nerve extends to the thoracic and abdominal cavities • Most cranial nerves are mixed nerves except: – Olfactory (I), Optic (II), and vestibulocochlear (VIII) are sensory nerves

Spinal Cord

• Enclosed in the vertebral column • Continuation of the brain stem • Extend from the foramen magnum to the first or second lumbar vertebra • Covered by meninges that extend beyond the spinal cord

31 Gray matter of spinal cord and spinal root

• Gray mater butterfly shape, surrounds the central canal • Ventral horn contains somatic motor neurons cell bodies that sends their axons out to the ventral root of the cord • Dorsal horn receives sensory axons. The cell bodies of sensory neurons are found in the dorsal root ganglion

White matter of the spinal cord

• Composed of myelinated fiber tracts (made up of axons ) • Divided into three regions in each side – Posterior column: has ascending tracts ( sensory) – Lateral and anterior columns has both ascending and descending (motor) tracts

32 Peripheral nervous system

• outside the central nervous system • Consist of: – nerves – ganglia

Structure of a Nerve

• A nerve is a bundle of neuron fibers outside the CNS. • Mixed nerves carry both sensory and motor fibers

33 Spinal nerves and nerve plexuses

• Spinal nerves – 31 pairs – Named for the region of the cord from which they arise from (cervical, thoracic, lumbar, sacral) • plexuses: – four plexuses that innervate the limbs

Autonomic Nervous System

• Two divisions have opposite effect – Sympathetic – Parasympathetic • Most organs have both innervations

34 Parasympathetic Division • Also called rest and digest • Active when the body is at rest • Allows us to conserve energy • Located in brain nuclei of four cranial nerves (III, VII, XI, X) send out their axons in cranial nerves to serve the organ in the head and neck region, and abdomen • Located in the sacral region (S2 through S4) of the spinal cord. They leave the spinal cord to pelvic cavity

Sympathetic division

• Also called fight-or- flight • Located in the spinal cord between T1 through L2 • Increase heart rate, blood pressure, glucose level, dilate bronchioles in the lungs, dilate blood vessels in skeletal muscle, withdrawal of blood from digestive organs

35 Special Senses

Senses

• Special senses – Taste, Smell, Sight, Hearing and balance – Large, complex sensory organs ( eyes, ears)

36 • Eye ball External and – Sphere, enclosed and protected accessory structures by the bony orbit • Eyelids: – protect the eyes anteriorly – Meet at the corners of the eye to form medial and lateral canthus • Eyelashes: – projecting from the border of each eyelid • Meibomian glands: – modified sebaceous glands in the eyelid – Produce oily secretion that lubricates the eye

Extrinsic Eye Muscles • Six muscles attach to the outer surface of each eye • Produce gross eye movement

37 Lacrimal apparatus

• Lacrimal gland – located above the lateral end of each eye – Secret tears into the anterior surface of the eye • Lacrimal canals – located medially • Lacrimal sac • Nasal Lacrimal duct: – empties into the nasal cavity

Conjunctiva

• lines the eyelids and covers the outer surface of the eyeball • Ends at the edge of the cornea • Secretes mucus that lubricate and moisten the eyeball

38 Sclera • Outermost, thick, white fibrous connective tissue (white of the eye)

Cornea: • The anterior portion, transparent, allows light to enters the eye.

Choroid

• Middle, blood rich layer • Ciliary body (muscle) attaches the lens • Iris: color of the eye has a round opening called pupil which regulates the amount of light entering the eye

39 Retina

• inner most layer • Contains photoreceptors except in the optic disc (blind spot) where the optic nerve exits the eye • Rods: Allow us to see gray tones in dim light • Cons: for accurate, colored (green, blue, red) vision. Concentrated in fovea centralis of macula lutea

Lens

• Flexible biconvex structure • Held by the suspensory ligament attached to the ciliary body • Divide the eye cavity into anterior chamber that contain aqueous humor and posterior chambers contain vitreous humor

40 Light Refraction

• The lens focuses the light on the retina macula lutea • The lens refractive power changes to properly focus the light on the retina – More convex  more refraction – Flatter  less refraction

Visual fields and visual pathways to the brain

• Optic nerve • Optic chiasm: • Optic tract: • Optic radiation • Occipital lobe

41 Eye reflexes

• Photopupillary reflex: – the pupils constrict immediately when exposed to bright light – Prevent damaging the photoreceptors • Accommodation pupillary reflex: – when viewing close objects; provide acute vision

Anatomy of the Ear

• Three major ears: – External and middle ear involved in hearing only – internal ear involved in hearing and equilibrium

42 External ear

• Composed of Auricle and earlobe surrounding the external auditory opening • supported by cartilage except ear lobe. • External auditory canal is short, narrow ends at the ear drum which separates the outer from the middle ear • Ceruminous glands in the skin secrete cerumen

Middle Ear

• Small air-filled cavity within the temporal bone • Located between eardrum laterally and a bony wall medially • Contains Ossicles: three bones (hammer, incus, stapes) that transmit vibration from tympanic membrane to oval window • Auditory (Eustachian) tube links the middle ear cavity with the throat. It equalizes the pressure in the middle ear with the external ear

43 Inner Ear

• located within the temporal bone behind the eye socket • Three subdivisions: – Cochlea contains organ of Corti (hearing) – Vestibule and semicircular canal for balance

Mechanism of hearing

• Sound waves enter the external auditory canal to the eardrum to the ossicles to the inner ear to the receptor cells in the organ of corti • The impulse carried by the cochlear nerve to the auditory cortex in the temporal lobe

44 Chemoreceptor

• Two kinds – Olfaction ( smell): wider range – Taste : four types

Olfactory receptors & sense of smell

• Olfactory receptors: – Very sensitive; pick up small differences – located in the roof of each nasal cavity • Olfactory pathway – Chemicals dissolve in mucus and stimulate the receptors. Then olfactory nerve carry it to the olfactory cortex • Olfactory pathway tied to limbic system (emotions) • Anosmias: – Loss of smell sensation due to trauma, inflammation, allergy • Olfactory auras: – olfactory hallucinations

45 Olfactory epithelium & pathway

Taste Buds & Sense of Taste • Four basic taste sensations: – Sweet: respond to sugar, saccharine, amino acids – Sour: acid – Bitter: alkaloids – Salty: metal ions • Other flavors are combination of the four tastes • Affected by sense of smell

46 Taste Buds & Sense of Taste

• Taste Buds – Receptors of taste sensation Found mostly on the tongue. – few taste receptors found in the soft palate and inner surface of the cheeks.

Endocrine System

47 The endocrine system • The Organs of the endocrine system are small. They Coordinates and directs the activity of the cells • Hormones released into the blood and transported throughout the body

Mechanisms of Hormone Action • Hormones attach to specific receptors on/in the cell and alter the cellular activity • Regulates processes such as: – Reproduction – Growth and development – Mobilizing body defenses against stressors – Maintaining electrolyte, water and nutrient balance of the blood – Regulating cellular metabolism and energy balance – Maintaining body homeostasis.

48 Steroidal hormones • Lipid-soluble molecules • binds to a specific receptor and to a specific sites on the cell’s DNA activating certain genes which result in the synthesis of new proteins.

Nonsteroidal hormones, protein and peptide hormones • The hormones binds to receptors on the target cell’s plasma membrane

49 Control of Hormone Release

• The stimuli that activate the endocrine organs fall into three major categories 1. Hormonal 2. Humoral 3. Neural

Hormonal stimulus

• Hypothalamic hormones stimulate the anterior pituitary gland to secrete its hormones • Anterior pituitary hormones stimulate other endocrine organs to release their hormones into the blood • As the hormones produced by the final target glands increase in the blood, they inhibit the release of anterior pituitary hormones; negative feed back