A&P Chapter 4

  1. Tissue
    Groups of cells that similar in structure and performam a common or related function are called tissues.
  2. What are the 4 basic types of tissue?
    • Epithelial
    • Connective
    • Muscle
    • Nervous
  3. What is the primary role of epithelial tissue?
  4. What is the primary role of connective tissue?
  5. What is the primary role of muscular tissue?
  6. What is the primary role of nervous tissue?
  7. Histology
    The study of tissue.
  8. Epithelial tissue
    a sheet of cells that covers a body surface or lines a body cavity
  9. Epithelial tissue occurs in the body as
    • covering and lining epithelium
    • glandular epithelium
  10. Apical Surface
    an upper free surface exposed to the body exterior or the cavity of an internal
  11. Basal surface
    lower attached
  12. apical-basal polarity
    cell regions near the apical surface fiffer from those near the basal surface both in structure and function.
  13. Microvilli
    fingerlike extenstions of the plasma membrane that increase the exposed surface area
  14. Cilia
    tiny hairlike projections that propel substances along their free surface
  15. Basal lamina
    • adjacent to the basal surface of an epithelium
    • thin supporting sheet
    • acts as a selective filter that determines which molecules diffusing from the underlying connective tissue are allowed to enter the epithelium
  16. Reticular lamina
    A layer of extracellular material containing a fine network of collagen protein fibers that "belong to" the underlying connective tissue.
  17. Basement membrane
    reinforces the epithelial sheet, helping it to resist stretching and tearing forces, and defines the epithelial boundry
  18. Innervated
    supplied by nerves fibers
  19. Avascular
    contains no blood vessels
  20. Epithelium is
    • 1. innervated-supplied by blood vessels
    • 2. avascular-contains no blood vessels
  21. How are epithelial cells nourished?
    The are nourished by substances diffusing from blood vessels in the underlying connective tissue
  22. Functions of epithelial
    • Protection
    • Absorption
    • Filtration
    • Excretion
    • Secretion
    • Sensory reception
  23. Simple epithlia
    • consist of a single cell layer
    • typically found where absorption, secretion, and filtration occur and a thin epithelial barrier is desirable
  24. Stratified epithlia
    • composed of two or more cell layers stacked one on top of the other
    • common in high abrasion areas where protection is important
  25. 3 common shapes of epithelial cell
    • squamous
    • cuboidal
    • columnar
  26. Squamous
    • flattened and scalelike
    • nucleus is a flattened disc
    • Can be stacked
    • Can be simple or stratified
  27. Cuboidal
    • boxlike, approximately as tall as they are wide
    • nucleus is spherical
    • Can be simple or stratified
    • has microvilli
  28. Columnar
    • tall and column shaped
    • nucleus is elongated from top to bottom
    • Do NOT layer
    • has microvilli
  29. Simple squamous epithelium
    • cells are flattened laterally, and they cytoplasm is sparse
    • in a surface fiew, the close fitting cells resemble a tiled floor
  30. Endothelium
    • inner covering
    • provides a slick, friction reducing lining in lymphatic vessels and in hollow organs of the cardiovascular system
  31. Mesothelium
    • middle covering
    • epithelium found in serous membranes lining of the ventral body cavity and covering its organs
  32. Simple cuboidal epithelium
    • Single layer of cells that are as tall as they are wide
    • important function are secretion and absorption
  33. Simple colmnar Epithelium
    • single layer of tall, closely packed cells, aligned like soldiers ina row.
    • lines digestive tract from the stomach through the rectum
    • mostly associated with absorption and secretion
  34. Pseudostratified columnar epithelium
    • Vary in height
    • all if its cells rest on the basement membrane, but only the tallest reache the free surface of the epithelium
    • cell nuclei lie at different levels above the basement membrane
    • secrets or absorbs substances
  35. All epithelial tissue have these 4 characteristics
    • Polarity
    • Attachment
    • Avascularity
    • Regeneration
  36. Transitional Epithelium
    • unique ability to stretch
    • stratified
    • Found in bladder
  37. Glandular Epithelium
    • collection of epitheliam cells that produce secretions
    • tissue that forms glands
    • classified by where product goes
  38. Exocrine
    glandular epithelium which secrets its product on to a surface

    Ex: mucus, digesitve, enzymes, and milk
  39. Endocrine
    release their secretions into the fluids and blood
  40. 3 ways exocrine glands secrete
    • exocytosis
    • apocrine
    • holocrine
  41. Exocytosis
    merocrine glands produce and package the product in the cytoplasm and then transport it to the cell membrane where it is then expelled.

    Ex: Sweat glands are a type of merocrine
  42. Aprocrine
    • packs the apical portion of the cell with vesicle containing the secretory product. All get shed
    • a piece of the cell is lost with its products are lost
    • Ex: Milk production
  43. Holocrine gland
    • the whole cell is destroyed when the product is released.
    • Ex: hair
  44. Hormones
    Regulate and coordinate the activities other tissues, organs and organ systems
  45. Unicellular glands
    • mucous cells-epithelial linings of the intestinal adn respiratory tracts
    • goblet-cuplike accumulation of mucin distends the top of the cell making the cells looke like a glass with a stem
  46. Mulitcellular exocrine glands
    • have 2 basic parts:
    • an epithelium derived duct
    • secretory unit (acinus) consisting of secretory cells
  47. Connective tissue
    Most abundant in the body
  48. 4 Main classes of connective tisse
    • Connective tissue proper
    • Cartilage
    • Bone tissue
    • Blood
  49. 4 major functions of connective tissue
    • Binding & support
    • Protection
    • Insulation
    • Transportation
  50. Common characteristics of connective tissue
    • Common origin-all connective tissues arise from mesenchyme (embryonic tissue)
    • Degrees of fascularity-connective tissue run the enitre gamut of vascularity
    • Extracellular Matrix-non-living
  51. Connective tissues have 3 main elements
    • ground substance
    • fibers
    • cells
  52. Ground substance and fibers make up the
    extracellular matrix
  53. Ground substance
    • Unstructured material that fills the space between the cells and contains the fibers.
    • Holds large amounts of fluid and functions as a molecular sieve through which nutrients and toher dissolved substances and ciffuse between the capillaries and cells
  54. 3 types of fibers founhd in connective tissue matrix are
    • Collagen-
    • Elastic
    • Reticular fibers
  55. Collagen fibers
    • Strongest and most abundant
    • Constructed primarily of the fibrous protein collagen
  56. Elastic fibers
    • Long, thin fibers that form branching networks in the extracellular matrix.
    • Contain a rubber-like protein, elastin, which allows them to stretch and recoil like rubberbands
    • Found where greater elasticity is needed
  57. Reticular fibers
    • Short, fine collagenius fibers with a slightly different chemistry and form.
    • Continuous with collagen fibers, and they branch extensively forming delicate networks
  58. Fundamental cell type thas exists in immature and mature forms
    • 1. Connective tissue proper-fibroblast
    • 2. Cartilage-chondroblast
    • 3. Bone-osteoblast
    • 4. Blood-hematopoietic stem cell
  59. Mast cell
    • typically cluster along blood vessels
    • Act as sensitive sentinels to detect foreign microorganisms (bacteria, fungi) and initiate local inflammatory responses against them
  60. Macrophages
    • macro=large
    • phago=eat
    • large irrecularly shaped cells the avidly phagocytize a bread variety of foreign material
  61. Mesenchyme
    • common embryonic tissue
    • derived from embryonic mesoderm (middle embryonic cell layer)
  62. Connective tissue proper
    • 2 sub classes:
    • loose connective tissue (areolar, adipose, reticular)
    • dense connective (dense regular, dense irregular, and elastic)
  63. Areolar Connective Tissue
    • classified as loose connective tissue
    • supporting and binding other tissues
    • holding body fluids
    • defending against infection
    • storing nutrients as fat
    • contains fibroblasts
    • Most abundant in the body
  64. Adipose tissue
    • similar to adipose in structure and function
    • cells packed closely together (like chicken wire)
    • richly vascularized
  65. Reticular connective tissue
    • resembles areolar connective tissue, but the only fibers in its matrix are retucular fibers
    • largely in lymph nodes, spleen, and bone marrow
  66. Dense regular connective tissue
    • Gel-like matrix with all 3 fiber types
    • contains fibroblasts, macrophages, mast cells, and some white blood cell
    • Wraps and cushions organs
    • Plays important role in inflammation
    • Holds and conveys tissue fluid
    • Widely distributed under epithelia of body...forms lamina propria of mucous membrane
    • Packages organs
    • surround capillaries
  67. Dense irregular connective tissue
    • Primarily irregularly arranged collagen fiber
    • Major cell type is fibroblast
    • Able to withstand tension exerted in many directions and provides structural stength
    • dermis of skin
    • submucosa of digestive tract
  68. Elastic connective tissue
    • dense regular connective tissue containing a high proportion of elsatic fibers
    • Allows for recoil of tissue following stretching
    • Maintains pulsatile blow of blood through arteries
    • Walls of large arteries
  69. Cartilage
    • Stands up to both tension and compression
    • Qualities are between dense connective tissue and bone
    • Lacks nerve fibers and is avascular
    • Chondroblasts are its main cell type
  70. 3 varieties of cartilage
    • Hyaline Cartilage
    • Elastic Cartilage
    • Fibrocartilage
  71. Hyaline Cartilage
    • Most abundant cartilage
    • Provides firm support with some pliability
    • Covers the head of long bones, tip of nose and sternum
  72. Elastic Cartilage
    • Found strength and stretchability are needed
    • ear
  73. Fibrocatrtliage
    • perfect strucutral intermediate between hyaline cartilage and dense regular connective tissue
    • found where strong strong support an dability to withstand heavy pressure is required
    • ex: intervertebral discs
  74. Bone (osseous tissue)
    • ability to support and protect the body structures
    • Bone matrix is similar in structure than cartilage but is harder and more rigid because it has and added matrix element
  75. Blood
    • fluid within blood vessels is he most atypical connective tissue
    • developes from mesenchyme and consists of blood cells
    • functions as the transport vehicle for the cardiovascular system
  76. Nervous tissue
    main component of the nervous system
  77. neurons
    • highly specialized nerve cells that generate and conduct nerve impulses.
    • branching cells with cytoplasmic extenstion
    • respond to stimuli
    • transmit electrical impulses over substantial distances
  78. Muscle tissues
    • highly cellular, well vascularized tissues that are responsible for most types of body movement
    • possess myofilaments
    • 3 types are:
    • Skeletal, cardiac and smooth
  79. Skeletal
    • tissue is packaged by connective tissue sheets into rogans called skeletal muscle that ate attached to the bones of the skeleton
    • Long, cylindrical cells that contain many nuclei.
    • Striated
    • Voluntary
  80. Cardiac
    • found only in the walls of the heart
    • striated
    • cells are uninucleate
    • has intercalated discs
  81. smooth muscle
    • its cells hsve no visible striations
    • spindle shaped and contain one centrally located nucleus
    • found mainly in the walls of hollow organs other than the heart
  82. 3 types of covering and lining membranes
    • cutaneous
    • mucous
    • serous
  83. Cutaneous membrane
    • Skin-organ system consisting of a keratinized stratified squamous epithelium firmly attached to a thick layer of dense irregular connective tissue
    • Exposed to air and is a dry membrane
  84. Mucous membranes
    • lines body caivties that open to the exterior, such as those of the hollow organs of the digestive, respiratory, and urogenital tracts
    • contain either stratified squamous or simple columnar
  85. serous
    • found in closed ventral cavities
    • simple squamous
  86. tissue repair
    • 1. Inflammation
    • 2. Organization
    • 3. Regeneration
Card Set
A&P Chapter 4
Chapter 4 Tissue