2 Epithelial Tissues Flashcards
What are the three morphological characteristics of epithelial cells?
Shape
Layers
Surface Specialisations
What is the function of simple squamous epithelium?
Mediates filtration and diffusion
Scale-like epithelial cells are known by what name?
Squamous
Epithelial cells which are as wide as they are tall are known as:
Cuboidal cells
What are the functions of simple cuboidal epithelium?
Absorption and Secretion
Nuclei of simple columnar cells are found at the base or the top of the cell?
Base
What structure connects simple columnar cells to one another?
Tight junctions
Cells which are taller than they are wide are known as?
Columnar
From where do columnar epithelial cells derive their nutrients?
Through the basement membrane
Do epithelial tissues contain capilliaries?
no
What are the functions of Simple Columnar Epithelial cells?
Protection
Absorption/Transportation (of nutrients)
Sensory
Some Simple Columnar Epithelial cells are innervated to provide sensory input, what areas of the body can they be found?
Cornea
Inner ear
Nose
Some simple columnar epithelial cells express cilia for movement of fluids, where can they be found?
Small Bronchi
Fallopian tubes
Auditory tubes
A layer of Columnar Epithelial Cells shows nuclei at differing heights above the basement membrane, what is this configuration called?
Pseudostratified
Can stratified epithelial cells express cilia?
no
Can pseudostratified Epithelial cells express cilia?
Yes
A sample of tissue shows a basal layer of columnar cells, followed by further layers flattening as they progress upwards towards the surface - what is this tissue called?
Stratified Squamous epithelium
What are the two main sub-types of stratified squamous epithelium?
Keritinizing
Non-Keritinizing
Some stratified squamous epithelial cells secrete a substance in order to make the tissue waterproof - what is this substance?
Glycolipid
Keritinization of cells serves what purpose?
Resisting mechanical abrasion
What is the name of cells which produce and fill with keratin?
Keratinocytes
In what areas of the body can non-keritinizing stratified squamous epithelium be found?
Oesophagus
Oral Cavity
Vagina
Sweat, mammary and salivary glands are typically comprised of what type of epithelia?
Stratified Cuboidal
How many layers are typical of stratified cuboidal epithelia?
Two
What are the three types of intercellular membrane specialties of epithelia?
Occluding
Adhering
Communicating
Tight junctions are also known as:
Zonula Occludens
Adhering junctions are also known as:
Zonula Adherens
and
Macula Adherens
Communicating junctions are also known as:
Gap Junctions
and
Nexus Junctions
The spot-weld like adhesions in zonula occludens are performed by which proteins?
Claudins
Occludins
Claudins and Occludins are found where?
Tight junctions / Zonula Occludens
What transmembrane proteins are involved in a zonula adherens?
Cadherins
Transmembrane Cadherins which bind to intermediate filaments within the cell are called:
Desmosomes
What is the type of adhesion found in a macula adherens?
Desmosomes
Do desmosomes bind by the actin filaments or intermediate filaments?
Intermediate filaments
Transmembrane proteins called Connexons can be found in what type of intercellular surface?
Gap junctions
Gap junctions serve what purpose?
Passage of nutrients and molecules between cells
What are the three luminal surface specializations of epithelia?
Cilia
Stereocilia
Microvilli
What is the function of Microvilli?
Greatly increasing surface area
Are stereocilia actively motile?
No
In what areas of the body can sterocilia be found?
Epididymis
Ductus Deferens
What is the function of Hemidesmosomes?
Anchoring epithelia to the basement membrane
What are the two classifications of exocrine glands?
Simple
Compound
Exocrine glands secrete their product to:
an external environment
Endocrine glands secrete their product to:
the bloodstream
What type of gland is this?

Compound Alveolar
(Acinar)
What type of gland is this?

Compound Tubular
What type of gland is this?

Compound Tubuloalveolar
What type of gland is this?

Simple Alveolar
What type of gland is this?

Simple Branched Alveolar
What type of gland is this?

Simple Branched Tubular
What type of gland is this?

Simple Coiled Tubular
What type of gland is this?

Simple Tubular
How does a Merocrine gland deliver its product?
Exocytosis
Which manner of secretion avoids damaging the secretory cell?
Merocrine
How does a holocrine cell deliver its secretory product?
Rupture of the cell membrane
How does an apocrine secretory cell deliver its product?
By breaking off vesicles