Session 1-microscopy,Epithelium,biopsy and staining techniques Flashcards
What is the unit Agstrom (A) 10 to the power of?
10 to the minus 10
What is a biopsy?
Removal of small piece of tissue from organ or body for microscopic examination
What is a smear test and what tissues is it used on?
Collect cells by exfoliation-smear on slide. Cervix, Buccal cavity
What is curettage and which tissue is it used on?
Remove tissue by scooping or scraping. Endometrial lining of uterus
What tissues is a needle used on?
Brain,breast,liver,kidney,muscle
Where is direct incision used to remove tissue?
Skin,mouth,larynx
Where are endoscopes used to remove tissue?
Lung,intestine,bladder
What compounds are used to fix tissue?
Water, ethanol and then embedded into wax with xylene/toluene
What causes shrinkage artefacts?
Dehydration then rehydration of slide
What colour does haemotoxylin stain acidic components of cells? (E.g. RNA and dna)
Purple/blue
What colour does eosin stain basic cell components? (E.g. Cytoplasmic proteins, extracellular fibres)
Pink
What colour does pas (periodic acid schiff) stain carbohydrates and glycoproteins?
Magenta
What is phase contrast?
Combines light waves to enhance image of unstained cells
What is confocal staining?
Tissue labelled with one or more fluorescent probes
What are the advantages of confocal methods?
Make 3D images, live specimens
What kind of surfaces have epithelial linings?
Skin-(exterior), (interior exposed to exterior)-GI tract, rest tract, gut, (interior not open to exterior)-pericardial sac,pleural sac, peritoneum, blood and lymph vessels
Give some examples of locations of simple squamous epithelia.
Line blood vessels (endothelium), lining body cavities (mesothelium), bowmans capsule, loop of henle, alveoli
Give some functions of simple squamous epithelium
Lubrication(mesothelium),gas exchange(alveoli),barrier(bowmans capsule),active transport as pinocytosis (mesothelium and endothelium)
What is histology?
Study of structures of tissues using staining and microscopy
Where would you find simple cuboidal epithelia?
Thyroid follicles,small ducts of exocrine glands,kidney Tubules (collecting duct)
Where would you find simple columnar epithelia?
Stomach lining,small intestine and large intestines (colon),gallbladder
Functions of simple columnar epithelia?
Absorption,secretion,lubrication,transport
Where would you find simple pseudostratified epithelia?
Lining of nasal cavity
What is stratified?
More than one cell layer thick
Where would you find stratified non keratinised squamous cells?
Oral cavity,larynx,vagina
What are the functions of non keratinised stratified squamous cells?
Protect against abrasion, reduces water loss
Where would you find keratinised stratified squamous cells?
Surface of skin
Where would you find stratified transitional cells?
Renal calyces (chambers of the kidney through which urine passes), ureters,urethras,bladder
Where is the basement membrane situated?
Lies between epithelial cells and connective tissue
What is the structure of a basement membrane?
Basal lamina (extra cellular matrix-molecules that provide structure to surrounding cells)
What is the function of a basement membrane?
Strong flexible layer to which epi cells adhere to
