click below
click below
Normal Size Small Size show me how
A & P Part 1
Tissue level of organization, skeletal system, joints, bone tissue
| Question | Answer |
|---|---|
| Tissue | group of similar cells with the same embryonic origin & function |
| Histology | science that studies tissues |
| Four main body tissues | 1) epithelial tissue, 2) connective tissue, 3) muscle tissue, 4) nervous tissue |
| Epithelial tissues (epithelia) | covers surfaces: lines hollow organs, cavities, ducts, forms glands; avascular: nutrition and gas exchange through diffusion; high rate of cell divisions, constant renewal of epithelial cells |
| Function of epithelial tissue | protection, filtration, secretion, absorption, excretion |
| Main types of epithelial tissue | 1) glandular, 2) covering and lining |
| Cell junctions | contact points between neighboring cells; Tight, Adherens Junctions, Desmosomes, Hemidesmosomes, GAP |
| Tight junctions | prevent passage of substances between cells |
| 2. Adherens Junctions, Desmosomes, Hemidesmosomes | strong, prevent separation of cells |
| GAP Junctions | allow cells to communicate, exchange ions |
| Apical/free surface | exposed to exterior, body cavity, lumen of organ |
| basal surface | Attached to adjacent connective tissue |
| lateral surface | face adjacent cells |
| basement membrane | Attachment between basal surface & underlying connective tissue |
| Classification of covering & lining epithelia | 1) According to cell shape, 2) According to arrangement of cells into layers |
| Classification of covering & lining epithelia according to cell layers | simple (single layer), stratified (two or more layers), pseudostratified (single layer appearing stratified) |
| Classification of covering & lining epithelia according to cell shape | Squamous (flat), cuboidal (cuboidal or hexagonal), columnar (tall, cylindrical), transitional (changeable shape, able to expand) |
| Glandular epithelia | exocrine, endocrine glands |
| Gland | one cell or group of specialized epithelial cells that secrete substances |
| Exocrine glands | secrete products into ducts, body surface or hollow organ |
| Endocrine glands | secrete products (hormones) into extracellular fluid, diffusion into blood |
| Connective tissue | most abundant tissue in body, binds, supports, strengthens, protects, insulates, separates, stores energy, transports |
| Structure of connective tissue | 1) cells, 2) matrix |
| Matrix of connective tissue | extracellular, fibers, ground substance |
| Cells of connective tissue | blasts, cytes, different types of white blood cells |
| Blasts | immature, high rate of cell divisions, metabolically active, produce matrix (fibroblasts, chondroblasts, osteoblasts) |
| Cytes | mature, reduced ability to divide and produce matrix (fibrocytes, chondrocytes, osteocytes) |
| Ground substance of matrix | between cells & fibers, fluid, semifluid, gelatinous, calcified; stores water, facilitates exchange of substances and metabolism; contains complex polysaccharides and proteins |
| Fibers of matrix | collagen, elastic, reticular |
| Collagen fibers of matrix | strong and flexible, most abundant protein in the body (25%) |
| Elastic fibers of matrix | thinner, elastic; in skin, blood vessels and lungs |
| Reticular fibers of matrix | fine bundles (stroma); supporting framework of many organs |
| Classification of mature connective tissue | Loose, dense, cartilage, bone, liquid |
| Loose connective tissue | soft, areolar connective tissue, adipose tissue, reticular connective tissue |
| Dense connective tissue | rough, dense regular, dense irregular and elastic connective tissue |
| Cartilage of connective tissue | hyaline, elastic and fibrocartilage |
| Liquid connective tissue | blood, lymph |
| Muscular tissue | 1) skeletal, 2) cardiac, 3) smooth |
| Tissue repair | replacement of worn-out, damaged or dead cells; from stroma, from parenchyma |
| Tissue repair from stroma | supporting connective tissue, fibrosis |
| Fibrosis | scar tissue formation |
| Tissue repair from parenchyma | functioning part of tissue/organ, regeneration |
| Factors affecting ability to regenerate | 1) type of tissue, 2) severity of injury, 3) status of patient, 4) amount of blood supply |
| Membranes | 1) epithelial 2) connective tissue |
| Epithelial membranes | composed of epithelium and underlying connective tissue; 1) Mucous, 2) serous, 3) cutaneous |
| Mucous membrane | lining of body cavities open to exterior, underlying connective tissue (lamina propria), goblet and other cells produce mucous |
| Serous membrane | lining of cavities not open to exterior, simple squamous epithelia and thin layer of areolar CT, parietal (lines cavity) & visceral (lines organs) |
| Serous fluid | between sheets of serous membrane |
| cutaneous membrane | skin |
| Connective tissue membranes | composed of connective tissue only; synovial |
| Synovial membrane | lining of freely moveable cavities, production of synovial fluid |
| Bones in human body | 206, most paired |
| Types of bones | long, short, flat, sesmoid, irregular, sutural |
| Sesmoid bones | in some tendons; protection, improvement of mechanical advantage at joint; variable, not always completely ossified, very small except for patellae |
| Bone surface markings | structural features adapted for specific functions, not present at birth, develop in response to forces applied to bones |
| Forces applied to bones | tension, compression |
| Tension | deposition of new bone, raised rough areas |
| Compression | results in depressed areas |
| Types of surface markings | depressions & openings, processes |
| Bones in axial skeleton | 80 bones |
| Skull bones | 22, 8 cranial, 14 facial |
| Cranial bones | Frontal, parietal, temporal, occipital, sphenoid, ethmoid |
| Facial bones | Nasal, maxilla, zygomatic, lacrimal, palatine, vomer, mandible, inferior nasal conchae |
| Orbits | contain eyeballs and associated structures, 7 bones form each of them |
| Nasal septum | perpendicular to plate of ethmoid bone |
| Sutures | immovable joints found only between skull bones, moveable in children, coronal, sagittal, lambdoid, squamous |
| Paranasal sinuses | cavities in some bones of skull; lined with mucous membranes continuous with lining of nasal cavity (frontal, sphenoid, ethmoid, maxillary) |
| Fontanels | areas of unossified mesenchyme between cranial bones of infants, disappear after 24 months |
| Hyoid bone | doesn't articulate with any other bone, connected with the rest of skeleton by ligaments and muscles |
| Vertebral column | spine, backbone, 26 vertebrae |
| Normal curves | primary (thoracic & sacral), secondary (cervical & lumbar) |
| Abnormal curves | kyphosis (hunchback), lordosis (sway back), scoliosis |
| Intervertebral discs | between vertebrae, annulus fibrosus, nucleus pulposus |
| Vertebrae | body, arch (lamina), processes (transverse, spinous, articular), vertebral foramen & notches, facets |
| Regions of vertebral column | cervical (7), thoracic (12), lumbar (5), sacrum, coccyx |
| Cervical region | transverse foramen & process, atlas (C1), axis (C2, dens), vertebral prominens (C7) |
| Thoracic region | transverse process, body's |
| Lumbar region | large body's |
| Sacrum | base, apex, fused 5 sacral vertebrae |
| Coccyx | fused 4 coccygeal vertebrae |
| Thorax (thoracic cage) | Sternum, ribs |
| Sternum | manubrium, angle, body |
| Ribs | 12 pairs, 7 true, 5 false, 2 floating |
| Appendicular skeleton | pectoral (shoulder) girdle, pelvic (hip) girdle, upper extremity, lower extremity |
| Pectoral (shoulder) girdle | clavicle, scapula |
| Clavicle | sternal end, acromial end |
| Scapula | body, borders (medial, lateral), angles (superior, inferior), processes, fossae, glenoid cavity |
| Upper extremity | 30 bones, humerus, ulna, radius, carpals, metacarpals, phalanges |
| Pelvic girdle | coxal bones (ilium, ischium, pubis) |
| Lower extremity | 30 bones, femur, patella, tibia, fibula, tarsals, talus, calcaneus, metatarsals, phalanges |
| joints | articulations |
| structural classification of joints | space between articulating bones and type of binding connective tissue (fibrous, cartilaginous, synovial) |
| Functional classification of joints | degree of movement; synarthrosis (immoveable), amphiarthrosis (slightly moveable), diarthrosis (moveable) |
| Fibrous joints | lack synovial cavity, connected by fibrous connective tissue, (sutures, syndesmoses, gomphoses) |
| Sutures | synarthroses (become bone); thin layer of connective tissue, irregular, interlocking edges, between bones of skull |
| Syndesmoses | amphiarthroses, fibrous connective tissue, space between bones (little) |
| Gomphoses | synarthroses, dentoalveolar joints (teeth), socket & periodontal ligaments |
| Cartilaginous joints | lack synovial cavity; connected by hyaline cartilage or fibrocartilage (synchondroses, symphyses) |
| Synchondroses | synarthroses, epiphyseal plates (first rib & manubrium) |
| Symphyses | amphiarthroses, covered by hyaline cartilage, connected by disc of fibrocartilage, midline of body |
| Synovial joints | Diarthroses, synovial cavity, articular cartilage, capsule, synovial fluid, articular discs, bursae, tendon sheaths |
| Articular cartilage | hyaline, reduces friction, absorbs shock |
| Articular capsule | 1) fibrous capsule 2) synovial membrane |
| Fibrous capsule | dense fibrous, irregular & regular connective tissue |
| Synovial membrane | areolar connective tissue with elastic fibers; may include articular fat pads |
| Synovial fluid | viscous, clear-pale yellow, produced by synovial membrane, lubrication, gas & nutrient, exchange of articular cartilage, contains phagocytic cells |
| Articular discs | menisci, made of fibrocartilage, in some joints and not others |
| Bursae | pad-like structures; connective tissue lined with synovial membrane producing synovial |
| tendon sheaths | tube-like bursae; protection of tendons |
| Types of synovial joints | planar, hinge, pivot, condyloid, saddle, ball & socket |
| Factors affecting range of motions | 1) structure/shape of articulating bones 2) strength/tension of joint ligaments 3) arrangement/tension of muscles 4) contact of soft parts 5) hormones 6) use/disuse/aging/disease |
| Flexion | decrease in angle at joint |
| extension | increase in angle at joint |
| hyperextension | increase in angle at joint beyond anatomical position |
| abduction | movement away from midline |
| adduction | movement toward midline |
| circumduction | multi-planel, flexion, extension, hyperextension, adduction, abduction, rotation |
| Rotation | around long axis of bone |
| elevation | upward movement |
| depression | downward movement |
| protraction | movement anteriorly |
| retraction | movement posteriorly |
| inversion | soles medially |
| eversion | soles laterally |
| dorsiflexion | toes toward knees |
| plantar flexion | pointed toes |
| supination | palms up |
| pronation | palms down |
| opposition | thumb moves across palm to touch tips of fingers |
| Functions of bone tissue | support, protection, assistance in movement, mineral homeostasis, hemopoiesis (red bone marrow), triglyceride storage (yellow bone marrow) |
| Structure of bone | diaphysis, epiphyses, metaphyses, articular cartilage, periosteum, medullary cavity, endosteum |
| Diaphysis | shaft/body |
| Epiphyses | distal and proximal ends |
| Metaphyses | connections between diaphysis and epiphyses, include epiphyseal plate (becomes epiphyseal line) |
| Articular cartilage | thin layer of hyaline cartilage covering articulating part of epiphysis |
| Periosteum | dense irregular connective tissue surrounding bone surface (protection, growth in thickness) |
| Medullary cavity | in diaphysis; contains yellow bone marrow |
| Endosteum | membrane (connective tissue & bone forming & bone reabsorbing cells) lining medullary cavity |
| Bone histology | type of connective tissue, cells & extracellular matrix (ground substance, fibers) |
| Types of cells in bone | osteogenic, osteocytes, osteoblasts, osteoclasts |
| Osteogenic bone cells | stem cells along inner periosteum & endosteum; undergo cell divisions |
| Osteoblasts | bone-building cells; synthesize collagen, initiate calcification of extracellular matrix |
| Osteocytes | mature bone cells, maintain bone tissue |
| Osteoclasts | bone-resorbing (breaking/dissolving) cells (part of normal bone metabolism – remodeling) |
| Extracellular matrix | 25% water, 25% collagen fibers, 50% mineral salts (calcium phosphate, calcium hydroxide, calcium carbonate, magnesium, fluoride, potassium, and sulfate; calcification |
| Calcification | deposition of minerals (responsible for hardness) in framework of collagen fibers (responsible for flexibility and tensile strength) |
| Compact bone tissue | 80%, strongest form of bone, under periosteum of all bones, diaphysis of long bones |
| Structural units of bone tissue | osteons (haversian systems) |
| Osteons (haversian systems) | aligned along lines of stress, change according to function, central canal, perforating (Volkmann’s) canals, concentric lamellae, lacunae, canaliculi, circumferential & interstitial lamellae |
| Perforating (Volkmann’s) canals | connection with periosteum |
| Concentric lamellae | rings of calcified extracellular membrane |
| Lacunae | spaces containing osteocytes |
| Canaliculi | tiny channels containing processes of osteocytes and extracellular fluid |
| Interstitial lamellae | fragments of older osteons |
| Circumferential lamellae | encircle bone beneath periosteum |
| Spongy bone tissue | 20%, no osteons, lamellae arranges in trabeculae, spaces filled with red bone marrow, epiphyses of long bones |
| Blood and nerve supply (bones) | bones have rich blood supply, good healing potential, periosteum is rich in sensory nerves, nerves & veins accompany arteries, (periosteal, nutrient arteries) |
| Periosteal arteries | enter through many perforating (Volkmann’s) canals |
| Nutrient arteries | enters through nutrient foramen (near center of diaphysis) |
| Bone formation | osteogenesis (ossification), replacement of template made of connective tissue by osseous tissue, sixth week of embryonic development (intramembranous, endochondral) |
| Intramembranous ossification | bone formation within mesenchyme; embryonic connective tissue (flat bones of skull, mandible) |
| Endochondral ossification | mesenchyme, hyaline cartilage, bone formation, most bones in body, primary ossification centers (epiphyseal plate) |
| Epiphyseal plate | hyaline cartilage between epi- and metaphysis; responsible for length wise growth of long bones |
| Bone growth | length (interstitial), thickness (appositional) |
| Bone growth in length | epiphyseal plates, growth of cartilage and its replacement by bone, (close after puberty, replaced by epiphyseal line) |
| Bone growth in width | addition of new bone to the periphery by osteoblasts in periosteum; as new bone is deposited on the outside, osteoclasts in endosteum destroy bone on the inside – enlargement of medullary cavity |
| Bone remodeling | ongoing replacement of old bone tissue by new one (4% per year compact; 20% per year spongy), bone resorption (osteoclasts), bone deposition (osteoblasts), adaption to function |
| Factors affecting bone growth and remodeling | minerals, vitamins, hormones, sex hormones |
| Vitamins affecting bone growth and remodeling | C (collagen formation); K, B12 (protein synthesis); A (stimulation of osteoblasts); D (mineralization) |
| Minerals affecting bone growth and remodeling | Ca, P, Mg, F, Fe, Mn |
| Hormones affecting bone growth and remodeling | human growth hormone; thyroid hormones; parathyroid hormone; calcitonin |
| sex hormones and bone growth and remodeling | growth spurt, closure of epiphyseal plates |
| Fracture | break in bone |
| Repair of bone | 1) formation of fracture hematoma (6-8hrs); 2) formation of fibrocartilaginous callus (3 wks); 3) formation of bony callus (3-4 mos); 4) bone remodeling |
| Treatment of fractures | reduction (open/closed), immobilization |
| Osteoporosis | porous bones, loss of bone mass, bone resorption outpaces bone deposition; 80% of women |
| Problems associated with osteoporosis | fractures, shrinkage of vertebrae, height loss, hunched backs & bone pain |
| Prevention of osteoporosis | weight-bearing exercise, adequate calcium intake |
| Reasons women’s bones are less massive then men’s bones | 1) inactive lifestyles, 2) 2) production of estrogens in women decline dramatically at menopause (hormone replacement therapy) |
| Rickets (children) Osteomalacia (adults) | bones fail to calcify, organic matrix still produced but calcium salts are not deposited and bones become “soft” or rubbery and easily deformed; lack of Vitamin D, (deficiency in diet or lack of sun) |