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Epithelial Tissue (pg 2). Tissue = collection of cells that have similar structure and function together as a unit. Tissue = collection of cells that have similar structure and function together as a unit Histology = Study of tissues. Epithelial Tissues.
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Tissue = collection of cells that have similar structure and function together as a unit
Tissue = collection of cells that have similar structure and function together as a unit Histology = Study of tissues
Epithelial Tissues • Form the covering of all body surfaces, line body cavities and organs, and form glands
Epithelial Tissues • Form the covering of all body surfaces, line body cavities and organs, and form glands • Cells are tightly packed
Epithelial Tissues • Form the covering of all body surfaces, line body cavities and organs, and form glands • Cells are tightly packed • One free surface
Epithelial Tissues • Form the covering of all body surfaces, line body cavities and organs, and form glands • Tightly packed • One free surface • Avascular (no blood vessels)
Epithelial Tissues • Form the covering of all body surfaces, line body cavities and organs, and form glands • Tightly packed • One free surface • Avascular (no blood vessels) • Regenerate quickly
Shapes 1. Squamous = flat cells, thin nuclei
Shapes • Squamous = flat cells, thin nuclei • Cuboidal = cubelike cells, spherical central nuclei
Shapes • Squamous = flat cells, thin nuclei • Cuboidal = cubelike cells, spherical central nuclei • Columnar = Tall narrow cells, nuclei near bottom
Number of Layers • Simple = 1 layer
Number of Layers • Simple = 1 layer • Stratified = Multiple layers of cells. Named according to the type of cells at the free surface of the tissue
Number of Layers • Simple = 1 layer • Stratified = Multiple layers of cells. Named according to the type of cells at the free surface of the tissue • Pseudostratified = appears to be multiple layers, but is really only 1 layer
Glandular Epithelium • Exocrine glands = secrete products onto a surface via a duct
Glandular Epithelium • Exocrine glands = secrete products onto a surface via a duct • Can be unicellular (goblet cells) or multicellular
Exocrine Glands Classified according to STRUCTURE 1. Simple: duct has no branches 2. Compound: duct has branches
Exocrine Glands Classified according to STRUCTURE 1. Simple: duct has no branches 2. Compound: duct has branches 3. Tubular: gland has the same diameter as the duct 4. Acinar (Alveolar): gland is saclike
Exocrine Glands Classified according to SECRETIONS 1. Merocrine: fluid released by exocytosis Example: salivary and pancreatic glands
Exocrine Glands • Classified according to SECRETIONS 1. Merocrine: fluid released by exocytosis Example: salivary and pancreatic glands 2. Apocrine: small portion of cell is pinched off Example: Mammary glands
Exocrine Glands • Classified according to SECRETIONS 1. Merocrine: fluid released by exocytosis Example: salivary and pancreatic glands 2. Apocrine: small portion of cell is pinched off Example: Mammary glands 3. Holocrine: Cells fill with product and rupture Example: Sebaceous (oil) glands
1st Period: 8:40-9:40 2nd Period: 9:45-10:45 3rd Period: 10:50-11:50 LUNCH: 11:50-12:24 4th Period: 12:30-1:30 ASSEMBLY: 1:35-2:25 5th Period: 2:30-3:30