Module 2 (LEC): Histology | Integumentary System Flashcards
Epithelial Tissue
- sheets of closely packed cells
- protection, exchange, secretion
Connective Tissue
- sparse cells in extracellular matrix
- building and support of other tissues
- bones (muscle attachment) & blood (transport)
Muscle Tissue
- moves when cells contract
Nervous Tissue
- cells comprising the nervous system in brain, spinal cord, and peripheral nerves
What are the steps for preparation of a specimen?
- obtain sample w/proper orientation
- fix/preserve specimen
- embed in support medium
- sectioning
- staining
- examination
Orientation
- improper orientation = damaged tissue
- embedded with least resistance to knife
Fix/Preserve
deactivate enzymes to prevent degradation
Embedding
prevent physical changes
Paraffin Wax Embedding
wax fills the tissue, supporting cellular components
Freezing
rapidly frozen in liquid nitrogen to harden the tissue
Sectioning
slicing of specimen with microtome
Methyl Blue
stains collagen blue
Hematoxylin and Eosin (H&E)
differentiation of nucleic acids in nucleus from proteins in cytoplasm
Hematoxylin
stains nuclei purple
Eosin
stains basic structures pink (proteins, membrane)
Van Gieson
stains connective tissue fibers (collagen, muscle, and elastic fibers)
Trichrome
- stain cellular components using three different dyes
- helpful for highlighting red blood cells within vessels
Silver Nitrate
- Golgi Method: stain whole tissue black (neurons)
Light/Optical Microscope
- beams of wavelengths through lens to magnify image
- magnification: 2,000x
- chromatic dyes to highlight tissue/cell components
Electron
- particle beams through magnetic lens to produce 2D and 3D images
- magnification: 2,000,000x
- stains by increasing electron absorption, electron dense heavy metals
Squamous
flat and plate like
Cuboidal
cube-like w/ similar height, width, and depth
Columnar
column shaped, height 2-3x width
Exocrine Glands
- glandular and duct portion
- secrete non-hormone products into ducts, carry to other organs or outside the body