Anatomy Unit 1 PDF - Human Body Systems

Dermatology: study and medical treatment of integumentary system Integumentary system consists of: skin, hair, nails, and associated glands Skin has 2 layers; the epidermis and dermis Thick skin is found: on the palms, soles, and corresponding surfaces of fingers and toes Thin skin covers rest of th...

Dermatology: study and medical treatment of integumentary system Integumentary system consists of: skin, hair, nails, and associated glands Skin has 2 layers; the epidermis and dermis Thick skin is found: on the palms, soles, and corresponding surfaces of fingers and toes Thin skin covers rest of the body Avascular: lacks blood vessels Subcutaneous fat: subcutaneous tissue that is composed predominantly of adipose tissue Eumelanin: brown and black coloring Pheomelanin: yellow-red coloring Friction ridges: fingerprint Flexion lines/creases: lines where skin folds at joints, skin is bounded deeper Ceruminous glands: modified apocrine glands found only in external ear canal; produces cerumen (earwax) Mammary glands: milk producing glands that develop in females during pregnancy and lactation First degree burn occurs at epidermis Second degree burn occurs through epidermis into dermis Third degree burn occurs through epidermis and dermis into the hypodermis. Autograft: tissue from another location on the same person’s body Allograft: tissue from unrelated person Skeletal System: composed of bones, cartilage, and ligaments joined to form a framework for the body. Osteology: the study of bone Cartilage: the forerunner of most bones and covers many joint surfaces Ligaments: hold bones together at joints Tendons: attach muscle to bone Compact bone: dense outer shell of bone Spongy bone: loosely organized bone tissue Epiphyseal line: remnant of childhood growth zone Periosteum: external sheath covering most of the bone Endosteum: thin layer of reticular connective tissue lining marrow cavity and all internal bone structures Osteoblast: bone growing cell Osteocyte: cell is in bone matrix as a regulator Osteoclast: surrounds ends of bones; dissolve bone Bone marrow: soft tissue occupying marrow cavities of long bones and small spaces of spongy bone Red bone marrow: contains multiple tissues including tissue that produces blood cells Yellow bone marrow: fatty marrow that does not produce blood Ossification or osteogenesis: the formation of bone Intramembranous ossification: produces flat bones of the skill, most of the clavicle, and part of the mandible ​ Building bone from bone Steps of intramembranous ossification:  1.​ Designate mesenchymal to osteoblasts which line them together, blood gets caught inside osteoblast circle, and matrix is being pushed out to form osteoid tissue 2.​ Osteoid tissue calcifies, osteoblasts become osteocytes 3.​ Expansion; forming trabeculae and periosteum spongy bone 4.​ Form compact bone with spongy bone in middle Endochondral ossification: bone develops from hyaline cartilage model; produces most bones of body ​ Building bone from cartilage Steps of endochondral ossification: 1.​ Cartilage model 2.​ Chondrocytes pull from matrix and group together to form periosteum, primary ossification, bony collar 3.​ Vascular invasion, primary cavity forms from blood, primary ossification center cells disappear, formation of secondary ossification center 4.​ Vascular invasion again; one epiphysis has one secondary marrow cavity 5.​ Epiphyseal plate at distal end; moves down 6.​ Adult bone, epiphyseal plate turns into plate, no longer growing. Metaphysis: cartilage replaced by bone ​ Functions: chondrocytes multiply, cessation of mitosis, temporary calcification of cartilage matrix, death of chondrocytes. Interstitial growth: cartilage growth from within Achondroplastic dwarfism: long bones stop growing in childhood Pituitary dwarfism: lack of growth hormone; short stature with normal proportions Wolff’s law of bone: architecture of bone determined by mechanical stresses placed on it Orthopedics: branch of medicine for prevention and correction of disorders of bones, joints, and muscles Stress fracture: break caused by abnormal trauma to a bone Pathological fracture: break in a bone weakened by disease Nondisplaced break: break in bone that does shift the bone placement Displaced break: break in bone the causes a shift in bone placement Comminuted break: multiple breaks in the bone into fragments Greenstick break: an incomplete break of bone; causes bent bone Steps of healing a bone fracture: 1.​ Hematoma formation 2.​ Soft callus forms from collagen and fibrocartilage 3.​ Hard callus forms with osteoblasts 4.​ Bone remodeling with osteoclasts Osteopenia: measurable decline in bone density; may advance in osteoporosis Osteoporosis: severe loss of bone density, bones easily fracture Axial skeleton: central support axis of body; skull, vertebrae, sternum, ribs, sacrum, hyoid Appendicular skeleton: pectoral girdle, extremities Fontanelles: spaces between unfused cranial bones Kyphosis: concave in anterior direction (curved outward toward back) Lordosis: conscience in posterior direction (curved outward toward front) Scoliosis: spine is shifted left or right Hyperkyphosis: hunchback spine Hyperlordosis: belly sticks out Muscular system: refers to skeletal muscles Mycology: the study of the muscular system Endomysium: thin sleeve of loose connective tissue around each fiber Perimysium: thicker layer of connective tissue that wraps fascicles Facicles: bundles of muscle fibers wrapped together Epimysium: fibrous sheath surrounding entire muscle Fascia: sheet of connective tissue between muscles or muscle groups Fusiform muscles: thick in the middle with fascicles converging on each tapered end Parallel muscles: uniform width and parallel fascicles Triangular (convergent) muscles: broad at one end with fascicles converging on the other, narrower end Pennate muscles: feather shaped ​ Unipennate: fascicles approach tendon from one side ​ Bipennate: fascicles approach tendon from both sides ​ Multipennate: bunches of feather converge to single point Circular muscles (sphincters): fascicles form rings around body openings and passages Direct attachment to bone- very little separation between muscle and bone Indirect attachment to bone- fibrous called tendons connect muscle to bone Prime mover: muscle that produces most of the force of a movement Antagonist: muscle that opposed the prime mover Fixator: muscle that prevents a bone from moving Innervation: muscle refers to the identity of the nerve that stimulates it A single muscle is typically innervated by one nerve Muscles for chewing: ​ Temporalis ​ Masseter ​ Buccinator ​ Orbicular Diaphragm: muscular dome between thoracic and abdominal cavities External intercostal muscles: most superficial layer; elevates ribs Internal intercostal muscles: deep; depress ribs I band: thin filaments (actin) H band: thick filaments (myosin) M line: line down a sarcomere Z disc to Z disc: one sarcomere A band: thick and thin filaments Thick filament: myosin filaments Thin filament: actin, tropomyosin, troponin Elastic filament: titin; springy protein Dystrophin: links actin in outermost myofilaments to membrane proteins that link to endomysium ​ Defects causes muscular dystrophy Motor unit: one nerve fiber and all the muscle fibers innervated by it Skeletal muscle cannot contract unless stimulated a nerve called somatic motor neurons Central Nervous system- brain and spinal cord Peripheral nervous system- nerves and ganglia Nerve: bundle of nerve fibers (axons) wrapped in fibrous connective tissue Ganglion: knot like swelling in a nerve where neuron cell bodies of PNS are concentrated Sensory nerves: composed only of afferent fibers; carry signals rom sensory receptors to the CNS Motor neurons: composed only of efferent fibers; carry signals from CNS to muscles and glands Mixed nerves: consist of both afferent and efferent fibers Visceral: insticitive Somatic: physical Schwann cells: envelop axons of PNS, form myelin sheath, assist in regeneration of damaged fibers Satellite cells: surround nerve cell bodies in ganglia of PNS, provide insulation around cell body, and regulate chemical environment Gliomas: tumors of glial cells; grow rapidly and are highly malignant Astrocyte: most abundant cell type in brain, most functional, binding function ​ Blood brain barrier Ependymal cell: lines the brain ​ Cerebrospinal fluid and neurons ​ Filtering system Microglia: helps fight invaders; immune system; protection Myelin sheath: spiral layers of insulation around an axon Myelination: production of sheath Multiple Sclerosis: oligodendrocytes and myelin sheaths deteriorate Oligodendrocytes- make myelin sheath Steps of nerve regeneration: 1.​ Axon distal to the injury degenerates, macrophages clean up tissue debris 2.​ Cell body swells, ER breaks up, and nucleus moves off center 3.​ Axon stump sprouts multiple growth processes 4.​ Shwann cell neurilemma, endoneurium, and basal lamina form a regeneration tube 5.​ Once contact is reestablished with original target, neurosome shrinks and returns to its original appearance Cerebrum: largest part of the forebrain Cerebral hemispheres: pair of half globes of cerebrum Longitudinal cerebral fissure: deep groove that separates the cerebral hemispheres corpus callosum: thick nerve bundle at bottom of longitudinal fissure that connects hemispheres Cerebellum: second largest part of the brain located in posterior cranial fossa. Brainstem: rest of the brain, includes: midbrain, pons, and medulla oblongata Gray matter contains nerve cell bodies, dendrites, and synapses ​ Cortex: surface layer of gray matter ​ Nuclei: depper masses of gray matter, surrounded by white matter White matte composed of tracts and is deep to cortical gray matter ​ Tracts: bundles of nerve fibers (axons) Meninges: three membrane surrounding brain and spinal cord ​ Dura mater ​ Arachnoid mater ​ Pia mater Ventricles: four internal, fluid filled chambers of the brain cerebrospinal fluid: clear, colorless liquid that fills the ventricles, canals of CNS Brain barrier system: regulates what substances can get from the bloodstream into tissue fluid of the brain Meningitis: inflammation of the meninges Blood CSF barrier- protects the brain at the choroid plexus Circumventricular organs- locations where the brain barrier system is absent Stroke: sudden death of brain tissue due to interruption of blood supply Thalamus: gateway to cerebral cortex, involved in memory and emotion Hypothalamus: homeostatic regulation of all body systems, memory, emotional behavior, circadian rhythms Epithalamus: relays information from the limbic system to the midbrain (pineal gland) Cerebrum: sensory perception, memory, thought, judgment, and voluntary motor actions Limbic system: important center of emotion and learning, reward and aversion Frontal lobe: thought, memory, decision making Parietal lobe: taste, visual processing, sensory integration Occipital lobe: visual awareness and processing temporal lobe: hearing, smell, emotion, learning, verbal memory Memory: information storage and retrieval Anterograde amnesia: unable to store new information Retrograde amnesia: person cannot recall things known before injury Wernicke area: recognition of spoken and written language (posterior speech area) Broca area: generates motor program for the muscles for speaking (motor language area) Left hemisphere: verbal memory, speech, right field vision and motor control, rational though Right hemisphere: memory, motor control of left hand, musical ability, creativity, nonverbal though