Epithelia & Glands Flashcards
(37 cards)
Is epithelia vascularised
No relied on BVs close to BM for nutrients etc
Difference between serous and mucous membrane and where would you find both?
Serous - lines closed cavities -e.g. peritoneum, pericardium, pleura
Mucus lines open cavities, e.g. resp, GI, GU
What are 3 categories of epithelia?
simple, stratified, pseudo stratified
What does a mucous membrane consist of? e.g. GI
- Epithelia (type depends on area)
- Lamina propria (CT)
- (sometimes) Muscular layer - muscularis mucosae
Where in the mucosal layers are Peyers patches found?
Lamina Propria
What do serous membranes consist of? e.g. pleura
2 layers with lubricating fluid in between
- Simple squamous epithelium
- Thin CT which attached epithelium to adjacent tissues, also carries Blood, nerves
Where would you find lamina propria in the body?
Mucosal membranes
What is a basement membrane’s function (2) and what’s it made of? How many layers? Which types of collagen?
Anchor epithelium to underneath loose connective tissue
Barrier to malignant cells & pathogens (filter). Made of thin fibrous ECM 2 layers - basal lamina (type IV collagen) and reticular connective tissue (collagen III)
Whats the order from the surface of BM, Epithelia, Connective tissue?
Epithelia
Basement membrane
Connective tissue
How are adjacent epithelia held?
tight junctions
Name 7 types of epithelia
transitional, cuboidal, columnar, squamous, pseudo stratified, stratified non keratinised, stratified keratinised.
Does the basement membrane contain any cells?
No, just fibres etc
What kind of epithelium would you find lining the body cavities - peritoneum (mesothelium) , pericardium, pleura. What function does it have?
Simple squamous
Diffusion/gas exchange/lubrication/coagulation
What kind of epithelium would you find in the kidney/ovaries/exocrine glands/thyroid follicles? What function does it have?
Simple cuboidal
Role in secretion/absorption/
protection
What kind of epithelia would you find lining the stomach, gastric glands, small intestine and colon? What function does it have?
Simple columnar epithelium ( with/without villi)
Role in absorption, secretion, lubrication, transport
What epithelium would would find in the lining of the nasal cavity, trachea,, bronchi? What function does it have?
Pseudostratified epithelium with villi.
Role in secretion of mucus and conduit (resp tract/ductus deferens), absorption
What epithelia would you find lining the vagina and the oesophagus? What function does it have?
Stratified squamous non-keratinised epithelium.
Protection from abrasion
Moist but reduces water loss
How does the vagina wall maintain low pH and why? What happens in the absence of hormones (e.g. before puberty/after menopause)?
Lactobacilli - convert glucose to lactate, reducing pH to suitable level to resist bacteria. Vagina is rich in glycogen which is where the lactobacilli get the glucose from. Only there with hormones so atrophy without.
What epithelia is found at the skin? What are the 4 layers? What is its function (4) ?
Stratified squamous epithelium keratinised.
Four layers are: Stratum
Corneum
Granulosum
Spinosum
Basale
Protection against abrasion
Prevents waterless
UV protection
Barrier to pathogens
Where does mitosis of keratinocytes occur? Where do they move from there? What do they form?
Basale, then move upwards to form the prickle layer.
What do keratinocytes produce? What role does this have in the epidermis?
Keratin - strength of the epidermis (think hair and nails)
What cell makes up the stratum corneum? What function does this layer have?
Corneocytes
Protection
What two other cell types are found in the epidermis and what do they do?
Melanocytes - dendritic cells - produce melanin gives skin colour and protects from UV damage
Langerhans cells - dendritic cells through prickle layer that are APCs to T cells. Role in skin allergic reaction
Where apart from lymph nodes might you find dendritic cells?
Skin - melanocytes, langerhan cells
