Advanced Biology Chapter 4 – Tissues Pgs. 109-111

Tissues Group of cells that perform a common or related function Epithelial Connective Muscle Nervous Study of Tissues

Covers body surface or lines a body cavity Tissues Covers body surface or lines a body cavity Skin, CV, Dig, Resp – Glands of body

6 roles as an interface tissue Protection Absorption Filtration Excretion Secretion Sensory Reception

Special Characteristics Close packed cells Form continuous sheets, bound by tight junctions and desmosomes

Special Characteristics Cells differ @ both surfaces Smooth, slick; free surface exposed to body exterior or cavity of internal organ Fingerlike extensions – increase surface area (line intestines or kidney) (look fuzzy – brushborder)

Thin supporting sheet, selective filter, is scaffolding for repair Hairlike extensions – propel things (line trachea) Bottom Thin supporting sheet, selective filter, is scaffolding for repair

Special Characteristics All epithelial sheets rest upon CT Deep to basal lamina – fine network of collagen fibers Basal + Reticular – reinforces

Special Characteristics Has nerves but no blood vessels

Special Characteristics High Regeneration Capability – if damaged, can grow back

Classification of Epithelia Single Cell Layer – absorption and filtration Multicellular – stacked; protection

Flat/Scalelike Cubelike (box), tall as wide Tall, column shaped – nucleus conforms to shape

Four Major Classes of Simple Epithelia Simple Squamous Simple Cuboidal Simple Columnar Pseudostratified Columnar

Four Major Classes of Stratified Epithelia Stratified Squamous Statified Cuboidal Stratified Columnar Transitional

Assignment Read Pg 111-115