Epithelium and glands Flashcards
Name 4 types of tissue
Muscular, Nerve, Epithelial, Connective
What are major characteristics of epithelial tissue?
Also name 5 functions
Demonstrates polarity (ie top&bottom (has basement membrane)), Rapid cell turnover, NO BLOOD VESSELS
Functions: 1.Absorption 2.Secretion 3.Protection 4.Sensory Perception 5.Transportation
Where are the following usually found?
1) Microvilli
2) Cilia
3) Stereocilia
4) Keratin
1) Columnar cells
2) Pseudostratified (eg respiratory, trachea)
3) Pseudostratified or columnar (eg epididymus)
4) Stratified squamous cells
Name 2 functions of simple squamous epithelial cells
- Transport (nutrient/gas exchange, molecules)
- Lubrication of organ surfaces
What membranes are made of simple squamous epithelial cells?
Mesothelium: lines external surfaces
Endothelium: lines internal surfaces
What is the defining characteristic of simple squamous endothelium?
Thin and flat
What do simple cuboidal epithelial cells typically form?
Ducts, tubules, & secretory cells (like in kidney)
What are 3 functions of Simple columnar epithelial cells?
- Absorption (nutrients)
- Secretion of mucus, enzymes, etc
- Protection
How can you tell keratin apart from other cells?
Usually in skin, keratin is stratified squamous epithelium that stains a dark pink
The vaginal epithelial layer is described as:
NON-KERATINIZED, stratified squamous epithelium
NOTE: If epithelium is stratified squamous epithelium, then it is implied to have kerain, so you must go out of your way to say non-keratinized if it doesn’t have keratin
Where is stratified cuboidal epithelium usually found?
Name 2 functions
Usually lines middle sized to large DUCTS.
- Secretion
- Absorption
Where is stratified columnar epithelium usually found?
Usually lining LARGE DUCTS
What is a common characteristic of pseudostratified columnar epithelium?
What are its functions?
Often has cilia or stereocilia on surface.
Protection, absorption, secretion.
NOTE: Not all cells reach lumen but ALL CELLS TOUCH BM
What type of epithelium is found in the bladder?
Transitional epithelium
How do exo/endocrine glands form differently?
Exocrine glands form from epithelial cell invaginations that stay connected to the surface.
Endo crine glands will not have any cells that connect them to the surface and will secrete things into the bloodstream.
Are ducts always involved in exocrine glands?
What about endocrine glands?
Yes.
No
Exocrine glands are based on:
1.Cell number 2.Type of secretion 3.Mode of secretion
What are 3 characterisitcs of goblet cells?
They are 1.unicellular gland cells that have the 2.nucleus in BASAL portion and the 3.secretory droplets (ie mucus) in APICAL portion
NOTE: They look like a wine glass
The majority of multicellular glands have ducts, which organ is the exception?
What kind of gland is formed here?
The lining of the STOMACH is the exception.
This lining forms a non-ducted, multicellular exocrine gland
NOTE: These are NOT goblet cells, usually in the stomach you will be able to see multiple droplets forming while goblet cells only form one
What is an acinus?
What is a parenchyma?
Acinus is a cluster of cells that resemble a many-lobed berry (eg rasberry)
A parenchyma is a cluster of cells that are functioning together for a purpose
What are the 3 types of secretion glands and what is characteristic of them?
1) Serous glands:Secrete peptides/proteins and they are GRANULAR
2) Mucous glands: secrete mucous and are clear
3) Seromucous glands: secrete both and are mixed
What are the 3 modes of secretion and their characteristics?
Holocrine: whole cell is secreted by plasma membrane burstin and cell being destroyed (most damaging type of secretion to cells) (found in hair and breast)
Apocrine: The product and top product of the plasma membrane is released (AKA decapitation secretion)
Merocrine: Just synthesized product released usually through exocytosis (least damagin)
Do endocrine glands have ducts?
NO
What is the diff b/w endo/exocrine tissue?
ENDOcrine tissue will have lots of BLOOD VESSELS in it
EXOcrine tissue will have DUCTS and connective tissue
