A&P ch 4

  1. tissues
    groups of cells similar in structure and function
  2. types of tissues
    • epithelial
    • connective
    • muscular
    • nerve
  3. nervous tissue function and location
    • internal communication
    • brain
    • spinal cord
    • nerves
  4. muscle tissue function and location
    • contacts to cause movement
    • muscle attached to bones (skeletal)
    • muscles of heart (cardiac)
    • muscles of walls of hollow organs (smooth)
  5. epithelial tissue function and location
    • forms boundaries between different environments, protects, secretes, absorbs, filters
    • skin surface (epidermis)
    • lining of GI tract organs and other hollow organs
  6. connective tissue function and location
    • supports, protects, binds other tissues together
    • bones
    • tendons
    • fat and other soft padding tissue
  7. 2 main types of epithelial tissue
    • covering and lining epithelia
    • glandular epithelia
  8. characteristics of epithelial tissue
    • 1 cells have polarity
    • - apical surface - may bear microvilli or cilia
    • - basal surface - noncellular basal lamina of glycoprotein and collagen lies adjacent to basal surface
    • 2 are composed of closely packed cells - continuous sheets held together by tight junctions and desmosomes
    • 3 supported by a connective tissue reticular lamina (under basal lamina)
    • 4 avascular but innervated
    • 5 high rate of regeneration
  9. classification of epithelia
    • 1 number of layers
    • - 1=simple
    • - >1=stratified
    • 2 type of cell
    • - squamous
    • - cuboidal
    • - columnal
  10. simple squamous epithelium- description, function, location
    • single layer of flattened cells with disc shaped central nuclei and sparse cytoplasm
    • allows passage of materials by diffusion and filtration in sites where protection is not important; secretes lubricating substances in serosae
    • kidney glomeruli, air sacs of lungs, lining of heart, blood vessels, lymphatic vessels, lining of ventral body cavity (serosae)
  11. endothelium
    lining of lymphatic vessels, blood vessels, heart
  12. mesothelium
    epithelium of serous membranes in the ventral body cavity
  13. simple cuboidal epithelium - description, function, location
    • single layer of cubelike cells with large spherical central nuclei
    • secretion and absorption
    • kidney tubules, ducts and secretory portions of sm glands, ovary surface
  14. simple columnar epithelium - description, function, location
    • single layer of tall cells with round to oval nuclei; some bear cilia; layer may contain mucus-secreting unicellular glands (goblet cells)
    • absorption; secretion of mucus, enzymes, and other substances; ciliated type propels mucus (or reproductive cells) by ciliary action
    • nonciliated type lines most of the digestive tract, gallbladder and excretory ducts of some glands; ciliated variety lines small bronchi, uterine tubes, and some regions of the uterus
  15. pseudostratified columnar epithelium - description, function, location
    • single layer of cells of differing heights, some not reaching the free suface; nuclei seen at different levels; may contain mucus secreting cells and bear cilia
    • secretion, particularly of mucus; propulsion o f mucus by ciliary action
    • nonciliated type in male's sperm-carrying ducts and ducts of lg glands; ciliated variety lines the trachea, most of the upper repiratory tract
  16. stratified squamous epithelium - description, function, location
    • thick membrane composed of several cell layers; basal cells are cuboidal or columnar and metabolically active; surface cells are flattened; in the keratinized type, the surface cells are full of keratin and dead; basal cells are active in mitosis and produce the cells of the more superficial layers
    • protects underlying tissues in aread sujected to abrasion
    • nonkeratinized type forms the moist linings of the esophagus, mouth and vagina; keratinized variety forms the epidermis of the skin, a dry membrane
  17. stratified cuboidal epithelium
    • quite rare
    • found in some sweat and mammary glands
    • typically 2 cell layers thick
  18. stratified columnar epithelium
    • limited distribution in body
    • sm amounts in pharynx, male urethra, and lining some glandular ducts
    • also occurs at transition areas between two other types of epithelia
  19. transitional epithelium - description, function, location
    • resembles both stratified squamous and stratified cuboidal; basal cells cuboidal or columnar; surface cells dome shaped or squamouslike, depending on degree of organ stretch
    • stretches readily and permits distension of urinary organ by contained urine
    • lines the ureters, urinary bladder, and part of the urethra
  20. gland
    one or more cells that makes and secretes an aqueous fluid
  21. gland classification
    • site of product release
    • - endocrine
    • - exocrine
    • relative number of cells forming the gland
    • - unicellular (goblet cells)
    • - multicellular
  22. endocrine glands
    • ductless
    • secrete hormones that travel through lymph or blood to target organs
  23. exocrine glands
    • more numerous than endocrine glands
    • secrete products into ducts
    • secretions released onto body surfaces (skin) or into body cavities
    • mucous, sweat, oil, salivary
  24. unicellular exocrine glands
    • goblet cell
    • - microvilli
    • - secretory vesicles
  25. multicellular exocrine glands
    composed of a duct and a secretory unit
  26. classification of multicellular exocrine glands
    • 1 duct type
    • - simple
    • - compound
    • 2 structure of secretory unit
    • - tubular
    • - alveolar
    • - tubuloalveolar
  27. simple tubular gland
    • duct doesn't branch
    • intestinal glands
  28. simple branched tubular
    • has "nubs"
    • stomach (gastric) glands
  29. compound tubular
    • definite branching
    • duodenal glands of small intestine
  30. simple alveolar
    • single "trunk"
    • alveolar = berry like
  31. simple branched alveolar
    • has "nubs"
    • sebaceous (oil) glands
  32. compound alveolar
    • definite branching
    • mammary glands
  33. compound tubuloalveolar
    • some are tubular some alveolar
    • definite branching
    • salivary glands
  34. modes of secretion
    • merocrine - secretion by exocytosis (pancreas, sweat, salivary)
    • holocrine - secretion by rupture of gland cells - cell blows up (sebaceous glands)
    • apocrine - secretion by blowing its top, reforms new top
  35. connective tissue
    most abundant and widely distributed tissue type
  36. 4 classes of connective tissue
    • connective tissue proper
    • cartilage
    • bone tissue
    • blood
  37. major functions of connective tissue
    • binding and support
    • protection
    • insulation
    • transportation (blood)
  38. characteristics of connective tissue
    • mesenchyme is their common tissue of origin
    • varying degrees of vascularity
    • cells separated by nonliving extracellular matrix (ground substance and fibers)
  39. structural elements of connective tissue
    • ground substance
    • fibers
    • cells
  40. ground substance of connective tissue
    • medium through which solutes diffuse between blood capillaries and cells
    • components
    • - interstitial fluid
    • - adhesion proteins
    • - proteoglycans - protein core + lg polysaccharides (chondroitin sulfate and hyaluronic acid); trap water in varying amounts, affecting the viscosity of the ground substance
  41. 3 types of fibers in connective tissue
    • 1 collagen (white fibers)
    • - strongest and most abundant type
    • - provides high tensile strength
    • 2 elastic
    • - networks of long, thin, elastin fibers that allow for stretch
    • 3 reticular
    • - short, fine, highly branched collagenous fibers
  42. cells of connective tissue
    • mitotically active and secretory cells - blasts
    • mature cells - cytes
    • - fibrocells in connective tissue proper
    • - chondroblasts and chondrocytes in cartilage
    • - osteoblasts and osteocytes in bone
    • - hematopoietic stem cells in bone marrow
    • - fat cells, white blood cells, mast cells, and macrophages
  43. mesenchyme
    • embryonic connective tissue
    • - gives rise to all other connective tissues
    • - gel-like ground substance with fibers and star-shaped mesenchymal cells
  44. connective tissue proper: loose connective tissue, areolar - description, function, location
    • gel-like matrix with all three fiber types; cells: fibroblasts, macrophages, mast cells, and some white blood cells
    • wraps and cushions organs; its macrophages phagocytize bacteria; plays important role in inflammation; holds and conveys tissue fluid
    • widely distributed under epithelia of body (forms lamina propria of mucous membranes); packages organs; surrounds capillaries
  45. connective tissue proper: loose connective tissue, adipose
    • matrix as in areolar, but very sparse; slosely packed adipocytes, or fat cells, have nucleus pushed to the side by large fat droplet
    • provides reserve food fuel; insulates against heat loss; supports and protects organs
    • under skin in the hypodermis; around kidneys and eyeballs; within abdomen; in breasts
  46. connective tissue proper: loose connective tissue, reticular - description, function, location
    • network of reticular fibers in a typical loose ground substance; reticular cells lie on the network
    • fibers form a soft internal skeleton (stroma) that supports other cell types including white blood cells, mast cells, and macrophages
    • lymphoid organs (lymph nodes, bone marrow, and spleen)
  47. connective tissue proper: dense connective tissue, dense regular - description, function, location
    • primarily parallel collagen fibers; a few elastic fibers; major cell type is the fibroblast
    • attaches muscles to bones or to muscles; attaches bones to bones; withstands great tensile stress when pulling force is applied in one direction
    • tendons, most ligaments, aponeuroses
  48. connective tissue proper: dense connective tissue, dense irregular - description, function, location
    • primarily irregularly arranged collagen fibers; some elastic fibers; major cell type is the fibroblast
    • able to withstand tension exerted in many directions; provides structural strength
    • fibrous capsules of organs and of joints; dermis of the skin; submucosa of digestive tract
  49. connective tissue proper: dense connective tissue, elastic - description, function, location
    • dense regular connective tissue containing a high proportion of elastic fibers
    • allows recoil of tissue following stretching; maintains pulsatile flow of blood through arteries; aids passive recoil of lungs following inspiration
    • walls of large arteries; within certain ligaments associated with the vertebral column; within the walls of the bronchial tubes
  50. cartilage: hyaline - description, function, location
    • amorphous but firm matrix; collagen fibers form and imperceptible network; chondroblasts produce the matrix and when mature (chondrocytes) lie in lacunae
    • supports and reinforces; has resilient cushioning properties; resists compressive stress
    • forms most of the embryonic skeleton; covers the ends of long bones in joint cavities; forms costal cartilages of the ribs; cartilages of the nose, trachea and larynx
  51. cartilage: elastic - description, function, location
    • similar to hyaline cartilage, but more elastic fibers in matrix
    • maintains the shape of a structure while allowing great flexibility
    • supports the external ear (pinna); epiglottis
  52. cartilage: fibrocartilage - description, function, location
    • matrix similar to but less firm than that in hyaline cartilage; thick collagen fibers predominate
    • tensile strength with the ability to absorb compressive shock
    • intervertebral discs; pubic symphysis; discs of knee joint
  53. other connective tissues: bone (osseous tissue) - description, function, location
    • hard, calcified matrix containing many collagen fibers; osteocytes lie in lacunae. very well vascularized
    • bone supports and protects (by enclosing); provides levers for the muscles to act on; stores calcium and other minerals and fat; marrow inside bones is the site for blood cell formation (hematopoiesis)
    • bones
  54. other connective tissues: blood - description, function, location
    • red and white blood cells in a fluid matrix (plasma)
    • transport of respiratory gases, nutrients, waste and other substances
    • contained within blood vessels
  55. 2 major cell types of nervous tissue
    • neurons
    • axons
  56. nervous tissue - description, function, location
    • neurons are branching cells; cell processes that may be quite long extend from the nucleus-containing cell body; also contributing to nervous tissue are nonirritable supporting cells
    • transmit electrical signals from sensory receptors and to effectors (muscles and glands) which control their activity
    • brain, spinal cord and nerves
  57. muscle tissues
    • highly cellular
    • well vascularized
    • responsible for most types of body movement
    • cells possess myofilaments
  58. skeletal muscle - description, function, location
    • long, cylindrical, multinucleate cells; obvious striations
    • voluntary movement; locomotion; manipulation of the environment; facial expression; voluntary control
    • in skeletal muscles attached to bones or occasionally to skin
  59. cardiac muscle - description, function, location
    • branching, striated, generally uninucleate cells that interdigitate at speciallized junctions (intercalated discs)
    • as it contracts, it propels blood into the circulation; involuntary control
    • the walls of the heart
  60. smooth muscle - description, function, location
    • spindle-shaped cells with central nuclei; no striations; cells arranged closely to form sheets
    • propels substances or objects (foodstuffs, urine, a baby) along internal passageways; involuntary control
    • mostly in the walls of hollow organs
  61. 3 covering and lining membranes
    • cutaneous
    • mucous
    • serous
  62. cutaneous membrane - description, location
    • keratinized stratified squamous epithelium attached to a thick layer of dense irregular connective tissue(dermis)
    • skin
  63. mucous membrane
    • moist membranes bathed by secretions or in the case of urinary mucosa, urine
    • line the body cavities that open to the exterior
    • - hollow organs of the digestive, respiratory and urogenital tracts
    • most contain either stratified squamous or simple columnar epithelia
    • epithelial layer is underlain by a layer of loose connective tissue called the lamina propria
    • some have a deeper layer of smooth muscle cells
    • absorption and secretion
  64. serous membranes
    • consists of simple squamous epithelium (mesothelium) resting on a thin layer of loose connective (areolar) tissue
    • mesothelial cells add hyaluronic acid to the fluid that filters fromt he capillaries in the associated connective tissue resulting in serous fluid
  65. steps of tissue repair
    • 1 inflammation
    • - severed blood vessels bleed and inflammatory chemicals are released
    • - local blood vessels become more permeable, allowing white blood cells, fluid, clotting proteins and other plasma proteins to seep into the injured area
    • - clotting occurs; surface dries and forms a scab
    • 2 organization
    • - the clot is replaced by granulation tissue, which restores the vascular supply
    • - fibroblasts produce collagen fibers that bridge the gap
    • - macrophages phagocytize cell debris
    • - surface epithelial cells multiply and migrate over the granulation tissue
    • 3 regeneration
    • - the fibrosed area matures and contracts; the epithelium thickens
    • - a fully regenerated epithelium with a underlying area of scar tissue results
  66. regenerative capacity of different tissues
    • very good regeneration - epithelial tissues, bone, areolar connective tissue, dense irregular connective tissue, and blood-forming tissue
    • moderate regen - smooth muscle and dense regular connective tissue
    • weak regen - skeletal muscle and cartilage
    • no functional regen - cardiac muscle and nervous tissue in the brain and spinal cord
  67. 3 primary germ layers
    • ectoderm - produces nervous tissue
    • mesoderm- produces muscle and connective tissues
    • endoderm - along with ecto and meso produce epithelium
    • these form all 4 of the tissues found in the body
  68. proliferation of body cells during development
    • nerve cells stop dividing ( or mostly) during fetal period
    • after birth the cells of most other tissues continue to divide until adult body size
    • tissues that regenerate throughout life
    • - epithelia
    • - blood-forming tissues
    • liver cells regenerate by division of adult cells
    • epidermis and cells lining intestine have abundant stem cells
  69. affects of aging on tissue development
    • epithelia thin
    • tissue repair is less efficient
    • bone, muscle and nervous tissues begin to atrophy
    • decreased circulatory efficiency leads to reduced delivery of nutrients to tissues
    • DNA mutations increase
  70. cancer
    disorganized cell growth
  71. neoplasm
    abnormal mass of proliferating cells
  72. benign
    • cells remain compacted
    • slow growth
    • often encapsulated
  73. malignant
    • nonencapsulated
    • grow relentlessly
    • cells invade their surroundings - metastasis
  74. proto-oncogenes
    • code for proteins that are essential for cell division, growth, and cellular adhesion
    • dmg (from carcinogens) can turn them into oncogenes
    • oncogenes may "switch on" dormant genes that allow cells to become invasive and metastasize
  75. tumor suppressor genes
    • suppress cancer by inactivating carcinogens, aiding DNA repair, or enhancing the immune system's counterattack
    • loss or malfunction of just 2 can lead to cancer
    • one prompts most cells to make proteins that stop cell division in stressed cells by promoting apoptosis or cell cycle arrest
Card Set
A&P ch 4