Epithelial cells Flashcards
apical specialisations
microvili
cilia
stereocilia
keratinisation
microvili function
increases surface area
cilia function
allows for movement or movement of substances along a surface
stereocilia function
forms specific functions in areas such as the male reproductive tract and ear
basolateral specialisations
anchoring junctions
gap junctions
tight junctions
anchoring junctions
junctions that mechanically join cells
- desmosomes
- hemidesmosomes
gap junctions
junctions between cells to allow for passage of chemical/electrical signals
tight junctions
junctions between cell, selaing them tightly
- abundantly found in the brain
desmosomes
lateral anchoring junctions
- between adjacent cells
hemidesmosomes
basal anchoring junctions
- between cell and basement membrane
keratinization
outer layer of keratin-filled epithelial cells
Simple squamous
- little protection
- for diffusion, filtration, some secretion, and absorption
- found lining blood vessels, the heart and alveoli, etc.
simple cuboidal
- protection from some toxic substances
- for diffusion, secretion and absorption
- found lining the kidnet tubules, glands, terminal bronchioles, etc.
simple columnar
- most protection of simple epithelia
- for movement of substances, absorption and secretion (often ciliated and containing goblet cells)
- found lining areas of the digestive tract
stratified squamous
- protection from abrasion
- for barrier against infection and water loss
- keratinised = skin
- keratinised = mouth, larynx, oesophagus, anus, etc
stratified cuboidal
- for secretion, absorption, and infection protection
- found in sweat gland ducts, salivary glands ducts, etc
- rare
stratified columnar
- for protection and secretion
- found lining the mammary gland ducts, larynx, male urethra, etc.
pseudostratified columnar
- for mucous production, secretion, and movement (almost always ciliated)
- found lining the nasal cavity, pharynx, trachea, bronchi, etc
transitional
special epithelia that changes shape depending on phase (cuboidal to squamous)
- found in the renal system
