Chapter 4: Epithelial Tissue Flashcards
2 Varieties Of Epithelial Tissues
- glandular tissue- perform secretion
2. covering + lining tissues- directly contact external environment
Glandular Tissue
perform secretion
Covering + Lining Tissues
directly contact external environment
ex: skin (epidermis)
Epithelial Characteristics
- consist of large #’s of closely packed cells = good barriers
- possess basement membranes
- tend to possess apical surface specialization
- avascular (no blood vessels)
- innervated (connective to nervous system; send + receive messages from nervous system)
- regenerate easily
Layer: Simple
one layer of cells
Layer: Stratified
2+ layers of cells (many layers)
Shape: Squamous
flat
Shape: Cuboidal
cubed; not tall nor wide(flat)
Shape: Columnar
tall
Simple Squamous Epithelium
one layer of flat cells
- found in places where ease of passage across epithelium is very important
ex: found lining lungs
Simple Cuboidal Epithelium
one layer of cubed cells (not so much tall or wide(flat) -performs secretion + absorption ex: kidney tubule- site of urine formation -secrete waste into urine -absorb water from urine
Simple Columnar Epithelium
one layer of tall cells
- performs secretion + absorption
- found in small intestine
Pseudostratified Ciliated Columnar Epithelium
falsely layered of tall cells
- function- protection
- location- Trachea (windpipe)
Stratified Squamous
many layers of flat cells
- most common epithelium
- function- protection (friction, abrasion)
- location- outer layer of skin; epidermis, esophagus(tube leads from throat to stomach)
Stratified Cuboidal
many layers of cubed cells
- function- protection, some secretion
- location- ducts of sweat glands
Stratified Columnar
many layers of tall cells
- function- protection
- location- part of male urethra (bladder to external environment)
Transitional Epithelium
function- distensible (stretches)
location- urinary bladder
