Epithelial tissue Flashcards
What is epithelia?
Sheets of contiguous cells, of varied embryonic origin, that cover the external surface of the body, and line the internal surfaces
What is the exterior epithelial lining?
Skin
What kind of epithelium is skin?
Keratinised, stratified, squamous
Is skin living or dead?
Outermost layer is dead, living underneath
Give 3 interior epithelial surfaces that open to the exterior
- Gastrointestinal
- Respiratory tract
- Genitourinary tract
Where does the GI tract start and end?
Mouth to anus
Where does the respiratory tract start and end?
Nasal cavity to alveoli
Give 5 epithelial surfaces that don’t open to the exterior
- Pericardial sac
- Pleural sacs
- Peritoneum
- Blood vessels
- Lymphatic vessels
What is the pericardial sac?
Sac that contains heart
What is the pleural sac?
Very thin sac that contains the lungs
What does the peritoneum contain?
Most of the gut contents
What do the blood vessels constitute?
The entire cardiovascular system
What is the epithelium a derivative of?
The 3 germ layers of the embryo
Describe the structure of the trilaminar embryonic disc
3 layers with motor cord in middle
What are the 3 layers in the trilaminar disc?
NAME?
What epithelium is derived from the ectoderm?
- Epidermis of skin
- Corneal epithelium of skin
What epithelium is derived from the mesoderm?
NAME?
What epithelium is derived from the ectoderm?
NAME?
What are the two main classifications of epithelia?
NAME?
What is meant by simple epithelium?
One cell layer thick
What is meant by stratified/compound?
More than 1 cell layer thick
What does all epithelium have?
A basal surface on the basement membrane
What is the basement membrane?
A thin, flexible, acellular layer that lies between epithelial cells and subtending connective tissue
What is meant by acellular?
Not made up of cells