lecture 3 anatomy review

tissue

a group of cells of similar structure that perform a common function

4 types of tissues:

• epithelial tissues: covering/lining of body surfaces and organs

• connective tissue: supportive tissues

histology

the microscopic study of tissues

characteristics of epithelial tissue

cellularity - sheets of connected cells

polarity - clear apical surface and basal surface

attachment - basement membrane

avascular - no blood vessels

innervated - nerves

regeneration - rapid rate of division (skin 4 weeks)

specialized contacts - cellular junctions

epithelial tissue

covers a body surface, lines a body cavity, and lines inner surface of organs

forms most glands

functions:

• protection - internal organs

• absorption

• diffusion - CO2 and O pass through

• filtration

• secretion

• sensory reception

classification of epithelial tissue

number of cell layers

• simple: 1 layer

• stratified: 2+ layers of cells

shape of cells in apical layer

• squamous: flat

• cuboidal: cube

• columnar: column