Biol 32 Tissue Lecture Notes

  1. Tissue:
    a "fabric" or group of cells with similar structure and function
  2. The Four primary types of tissues:
    • Epithelium (covering)
    • Connective (support)
    • Muscle (movement)
    • Nervous (control)
  3. What are the 3 types of microscopic tissues?
    • Histology
    • Biopsy
    • Autosy
  4. Epithelial tissue and glands:
    sheet of cells that cover all free body surfaces (inside and out), forming an interface between two environments 
  5. What are the functions of epithelium tissue?
    • Protection: often in areas that get scraped off
    • Absorption: intake of molecules and substances
    • Filtration: closely fitted cells can form a "strainer" with small holes
    • Secretion: release of molecules and substances
    • Senory reception
  6. Apical surface:
    • Macrovilli
    • Cilia
  7. Macrovilli
    • increase in surface area and used for absortion
    • fingerlike extentions of epithelial cells lining some parts of the digestive tract or kidney. may also create adhesion points for secreted mucus
  8. Cilia
    microtubules project from cell membranes as hair that moves uniformly in one direction (wave like). They can move substances along the surface of a sheet of epithelial cells. (nicotine decreases ciliary action)
  9. Lateral cell junctions:
    • Demosomes: linking protiens between cells
    • Tight Junctions: fuse adjacent plasma membranes together into leak proof sheets, seals extracellular space
    • Gap Junctions: allows substances to leak between cells <--->
  10. Basal Surface
    • Basal Lamina
    • Basement membranes
  11. Basal Lamina
    • 1) noncellular, adhesive sheet of glycoproteins secreted by epithelial cells toward the nighboring connective tissue layer.
    • 2) Functions: Selective filter, Scaffold to which epithelial cells can migrate or grow upon
    • 3) combines with fiber from CT layers to form basment membrain
  12. Basement membrane
    • 1) located just deep to basel lamina
    • 2) reinforces epithelial sheet and defines epithelial boundary
  13. Classifications of epithelium: # of cell layers
    • Simple: one layer
    • Stratified: more than one layer
    • Psedostratified: looks like more than one layer but isnt
  14. Classifications of epithelium: shape of cells
    • Squamous: flat, plate-like (nucleus: flat & disk-like)
    • Cuboidal: cube-shaped (nucleus: large & round)
    • Columnar: column-like (nucleus: oval, located in basal 1/3)
  15. Glandular Epithelium
    • 1) Glands: one or more epithelial cells organized to secrete a particual product (protien) - but not always
    • 2) Secretory pathway: RER --> Golgi --> vesicles --> exocytosis
    • 3) Two major gland types: endocrine and exocrine
  16. Endocrine glands
    • Ductless (secretion into the blood stream) 
    • each messenger (hormone) is manufactured to react with specific "target" organs and or cells. (ex: pancreas)
  17. Exocine Gland
    • 1) Secrete products to a body surface (ex: skin surface, body cavities. or passages leading outside)
    • 2) Unicellular (ex: single goblet cell secretes a protien called mucin) 
    • 3) Multicellular: secretory unit + duct (ex: sweat and oil glands)
  18. What are the 4 main connective tissues?
    • connective tissue proper
    • cartilage
    • osseous tissue (bone)
    • blood
  19. What are the functions for CT?
    • binding (connection) and support
    • protection (bones, blood)
    • insulation (fat)
    • transportation (blood)
  20. CT: Structure Elements - What are the different cell types?
    • 1) Fibrocyte
    • 2) Chondrocyte
    • 3) Osteocyte
  21. What is the extracellular matrix (ECM) composed of?
    • Ground Substances : holds water and ranges from liquid to jello firm; and is composed of:
    • Water 
    • Adhesion Protiens ex- demosomes
    • Polysaccaride molecules. 
    • Fibers : (fiberblasts) produced by cells and has 3 different types which consist of: 
    • Collegen fibers (strength) 
    • Elastic fibers (recoil) 
    • Reticular fibers (fine collagen, but more give)
  22. What are the 3 types of muscle tissue?
    • skeletal muscle
    • cardiac muscle
    • smooth muscle
  23. What are the 2 major types of nervous tissue?
    • Neuroglia (nerve support cells)
    • Nuurons (nerve cells)
  24. What are they functions of neurons?
    • Irritability (consents and responds)
    • Conductivity (sends impulses to other areas of the body)
  25. What are the common structural componets of nerve cells?
    • Dendrites (tend to be small and receive the signals, can have or be multiples)
    • Cell body
    • Axon - 1 per neron/cell or 1 message to be as specific as possible
    • Axonal (presynaptic) terminals - which is the end point of an axon and sends the message
  26. What are the 2 types of defenses in tissue repair?
    • External defenses (outside)
    • Internal defenses (inside)
  27. What does the External defense consist of?
    • Mechanical
    • Chemical
    • Microbiological
  28. What does the Internal defense consist of?
    • Inflammatory response - non specific and develops quickly (chemicals and some white blood cells)
    • Immune response - specific and takes longer (like antibiotics, some white blood cells)
  29. Repair occurs in 2major ways?
    • Regeneration
    • Fibrosis
  30. Regeneration
    is the replacement of destroyed tissue with same kind of tissue (ex - epithelium with epithelium)
  31. Fibrosis
    replacement of destroyed tissue with fibrous connective tissue (called scar tissue)
  32. What are the steps of tissue repair?
    • Inflammation
    • Organization
    • Regeneration and fibrosis
  33.  Regeneration capacity of Epithelial tissue?
    epithelial tissue, bone, areolar, and blood forming tissue regenerate extremely well
  34. Regeneration capacity of Smooth muscle?
    smooth muscles and dense regular connective tissue have a moderate capacity for regeneration
  35. Regeneration capacity of Skeletal muscle?
    skeletal muscle and cartilage have a weak regeneration capacity
  36. Regeneration capacity of Cardiac muscle?
    Cardiac muscle and nervous tissue in the brain and spinal cord have virtually no functional regeneration capacity and are routinely replaced by scare tissue
  37. What are the 3 types of membrans in epithelial + connective tissue?
    • Cutaneous membranes (skin)
    • Mucous membranes "mucosa" covers all portals to the inside and produces mucus
    • Serous membranes "serosa" line closed internal cavities and cover outside of organs, and produces serous fluid "lubrication"
  38. What is the membrane called in connective tissue?
    Synovial membrane - lines the inside of freely movable joints and produces synovial fluid "lubricant"
Card Set
Biol 32 Tissue Lecture Notes
Ch 4 tissue