Semester 1 Flashcards
Tissue
A collection of cells specialised to perform a specific function
Angstrom unit
10 to power of -10
Biopsy
The removal of a small piece of tissue from an organ/part of a body using microscopic examination
Types of biopsy
Smear - cervix
Curretage - endometrial lining of the uterus
Needle - brain, breast, kidney, liver, muscle
Endoscopy - intestine, liver, bladder
Transvascular - heart, liver
Direct incision - skin, mouth, larynx
Fixatives in tissue processing
Glutaraldehyde
Formaldehyde
Reasons why fixation is needed
Stops cell metabolism
Hardens the tissue
Kills pathogens and other microorganism so
Prevents enzyme degradation of cells and tissues by autolysis
Histology
The study of the structure of tissues by means of special staining techniques combined with light ad electron microscopy
Haematoxylin
Stains the acidic components of the cells purple/blue (nucleic acids)
Eosin
Stains basic components of the cell Pink (cytoplasm)
Periodic acid Schiff
Stains carbohydrates and glycoproteins magenta
Phase contrast microscopy
Uses light (in phase and out of phase) to get a high resolution and contrast in the micrograph.
All enhancement of images of unstained cells and it can be done on living cells
Dark field microscopy
Scattered light across the sample - can also be done on unstained and live samples. Good as usually background dark and the microbe etc is lighter. In other microscopy this may have been difficult when the microbe and background have similar refractive indexes.
Fluorescence microscopy
Target molecules of interest with fluorescence so that they shop up. They emit light of wavelengths of the visible light when exposed to the UV source
Confocal microscopy
Used on tissues labelled with one or more flourescent probes. Eliminates the out of focus flare as there is a detector aperture which only allows in focus light to get through. Can take 2D images at different depths and combine to make 3D image
Exterior surface with epithelial lining
Skin
Interior spaces opening to the exterior lined with epithelial
Respiratory tract
Gastrointestinal tract
Genitourinary tract
Interior surfaces not open to the exterior lined with epithalial cells
Blood vessels and lymphatic system
Peritoneum
Pericardium
Pleural sac
Trilaminar disc
Ectoderm - epithelial of skin, corneal epithelium in the eye
Mesoderm - 3Ps, blood vessels,
Endoderm
Basement membrane
Thin flexible layer that lies between the epithelial cells and subtending connective tissue. Basal lamina (epithelial cells) and reticular fibrils (connective tissue). Epithelial cells adhere to the basement membrane. Important for cancer prognosis
Simple squamous cells
Lining of blood and lymph vessels (endothelium)
3Ps - pericardium, peritoneum and pleural sac
