Anatomy

Which level?
Group of similar cells
Common embryonic origin
Common function

Covers body surfaces
Lines hollow organs, cavities and ducts
Forms glands

Material found between cells and organs
Supports and binds structures together
Stores energy as fat
Provides immunity to disease

Provides movement and generation of force

Cells that generate and conduct nerve impulses
Control and coordinate body functions

What are the 3 germ layers within the embryo?

Epithelium from all 3 germ layers
Connective tissue & muslce from mesoderm
Nerve Tissue from ectoderm

How many distinct layers do cells of embryonic disc produce?

Forms epithelial lining of FI & respiratory

Forms muscle, bone & other connective tissues

Develops into epidermis of skin and nervous system

Which type of Epithelium...
Epidermis of skin
Lining of blood vessels and ducts
Lining respiratory, reproductive, urinary and GI tract

Which type of Epithelium...
Secreting portion of glands
ex. thyroid, adrenal, and sweat glands

What are the 8 general features of epithelial tissue?

Which Basement Membrane:
From epithelial cells
Collagen fibers

Which Basement Membrane:
Secreted by connective tissue cells
Reticular fibers

Holds cells to connective ttissue
note: nerve supply BUT avascular

one cell layer thick

many cell layers thick

single layer of cells where all cells don't reach apical surface
(nuclei are found at different levels so it looks multilayered)

shape of surface cell: flat

shape of surface cell: cube-shaped

shape of cell surface: tall column

shape of cell surface: shape varies with tissue stretching

Lines blood vessels (endothelium), and body cavities (mesothelium)
Very thing -- controls diffusion, osmosis and filtration

Cells in direct contact with each other

Lines tubes of kidney
Absorption or secretion
Single layer of cube-shaped cells viewed from the side

Single layer rectangular cells
Unicellular glands
Microvilli

Goblet cells secrete mucus
(lubricate GI, respiratory, reproductive and urinary systems)

Fingerlike cytoplasmic projections
For absorption of GI tract (stomach to anus)

Single layer rectangular cells with cilia
Much from goblet cells moved along by cilia (found in repiratory system and uterine tubes)

Single cell layer
All cells attach to basement membrane but not all reach free surface
Nuclei at varying depths
Respiratory system, male urethra & epididymis

Several cell layers thick
Surface cells flat
Keratinized
Nonkeratinized

Surface cells dead and filled with keratin
-skin (epidermis)

No keratin in moist living cells at surface
-mouth, vagina

Multilayered
Surface cells cuboidal
-rare (only found in sweat gland ducts and male urethra)

Multilayered
Surface cells columnar
Rare (very large ducts & part of male urethra)

Multilayered
Surface cells varying in shape from round to flate if stretched
Lines hollow organs that expand from within (urinary bladder)

Derived from epithelial cells that sank below the surface during development

Glandular Epithelium:
Cells that secrete onto free surface of epithelial layer or into ducts
Unicellular glands or multicellular glands

Glandular Epithelium:
Secrete hormones into the bloodstream (ductless)
Hormones help maintain homeostasis

Exocrine Glands:
Unicellular are single-celled glands called ______

Exocrine glands:
Classified according to shape of duct: simple (unbranched) or compound (branched) ducts
Classified according to structure of gland: tubular or acinar (flask-liek)shape or both

unbranched ducts

branched ducts

flask-like shape

Methods of Glandular Secretion:
Most glands
Cells release their products by exocytosis
Eg saliva, digestive enzymes & sweat

found only in mammary gland
Upper part of cell pinches off and dies

Oil gland (sebaceous)
Whole cells die & rupture to release their products