Histology Terms Flashcards
Epithelium
-Characterized by close cell apposition and presence at a free surface.
-Epithelial tissue covers body surfaces, lines body cavities, and forms glands
-Contiguous layer of cells conjoined by inter-cellular junctions. Acting as a multicellular “membrane”, epithelia line surfaces, cavities, and lumen
-Further defined based on the morphology of the apical cell layer that faces the lumen. (Ex. squamous, cuboidal or columnar)
Nucleus
Function: Storage and use of genome
Pathology: Inherited genetic diseases; environmentally induced mutations
Nucleolus
Function: Synthesis of rRNA and partial assembly of ribosomal subunits
-Involved in regulation of cell cycle
Pathology: Werner syndrome (premature aging disease); Malfunctions of cell cycle leading to cancerogenesis
Plasma membrane
Function: Ion and nutrient transport, recognition of environmental signal, cell-to-cell and cell-to-extracellular matrix adhesions
Pathology: Cystic fibrosis, Intestinal malabsorption syndromes, lactose intolerance
rER
Function: Binds ribosomes engaged in translating mRNA for proteins destined for secretion or for membrane insertion. Also involved in chemical modifications of proteins and membrane lipid synthesis.
Pathology: Pseudoachondroplasia; Calcium phosphate dihydrate crystal deposition disease.
Simple epithelium
An epithelial “membrane” comprised of a single layer of cells.
Stratified epithelia
More than one layer of cells.
Pseudo-stratified epithelia
Appear to be multilayered as suggested by the distribution of their nuclei, but in higher resolution preparations all cells rest on the basement membrane, although not all cells extend up to the lumen/surface.
Transitional epithelium (urothelium)
Especially designed to accommodate the expansible nature of the urinary tract and bladder.
Endothelium
The blood vessels and lymphatics are lined by a simple squamous epithelium
Mesothelium
Epithelium lining peritoneal/pleural spaces
Pseudostratified epithelia
Appear to be multilayered as suggested by the distribution of their nuclei, but in higher resolution preparations all cells rest on the basement membrane, although not all cells extend up to the lumen/surface.
Serous cells
Protein secretor.
Chloroquine
An agent used in the treatment and prevention of malaria.
Gaucher disease
-Disorder of sphingolipid degradation
-Protein Deficiency: Glucocerebrosidase
-Accumulating Product: Glucosylceramide
Tay-Sachs disease
-Disorder of Sphingolipid Degradation
-Protein Deficiency: beta-hexosaminidase, alpha-subunit
-Accumulating Product: GM2 ganglioside
Sandhoff disease
-Disorder of sphingolipid degradation
-Beta-Hexosaminidase, beta-subunit
-Protein Deficiency: GM2 ganglioside, oligosaccharides
-Accumulating Product: GM2 ganglioside, oligosaccarides
Krabbe disease
-Disorder of sphingolipid degradation
-Protein Deficiency: Galactosylceramidase
-Accumulating Product: Gal-ceramide, gal-sphingosine
Niemann-Pick disease A, B
-Disorder of sphingolipid degradation
-Protein Deficiency: Sphingomyelinase
-Accumulating Product: Sphingomyelin
Disorders of Sphingolipid Degradation
1) Guacher Disease
2) Tay-Sachs Disease
3) Sandhoff Disease
4) Krabbe Disease
5) Niemann-Pick Disease A, B
Aspartylglycosaminuria
-Disorders of Glycoprotein Degradation
-Protein Deficiency: Aspartylglycosaminidase
-Accumulating Product: N-linked oligosaccharides
alpha-Mannosidosis
-Disorders of Glycoprotein Degradation
-Protein Deficiency: alpha-Mannosidase
-Accumulating Product: alpha-Mannosides
Hurler Syndrome (mucopolysaccharidosis I, MPS I)
-Disorders of Glycosaminoglycan Degradation
-Protein Deficiency: alpha-L-iduoronidase
-Accumulating Product: Derman sulfate, heparan sulfate
Hunter Syndrome (MPS II)
-Disorders of Glycosaminoglycan Degradation
-Protein Deficiency: L-Iduronate sulfatase
-Accumulating Product: Dermatan sulfate, heparan sulfate
Maroteaux-Lamy syndrome (MPS IV)
-Disorders of Glycosaminoglycan Degradation
-Protein Deficiency: GalNAc 4-sulfatase/arylsulfatase B
-Accumulating Product: Dermatan sulfate
Disorders of Glycoprotein Degradation
1) Aspartylglycosaminuria
2) alpha-Mannosidosis
Disorders of Glycosaminoglycan Degradation
1) Hurler syndrome (mucopolysaccharidosis I, MPS I)
2) Hunter syndrome (MPS II)
3) Maroteaux-Lamy syndrome (MPS IV)
Other Disorders of Single Enzyme Deficiency
1) Pompe Disease (glycogenosis II)
2) Wolman disease (familial xanthomatosis)
3) Canavan disease (aspartoacylase deficiency)
Pompe Disease (Glycogenosis II)
-Other disorders of single enzyme deficiency
-alpha-1,4-Glucosidase
-Accumulating Product: Glycogen
Wolman disease (familial xanthomatosis)
-Other disorders of single enzyme deficiency
-Acid lipase
-Cholesterol esters, triglycerides
Canavan disease (aspartoacylase deficiency)
-Other disorders of single enzyme deficiency
-Aspartoacylase
-Accumulating Product (or defective process): N-acetylaspartic acid
Disorders of Lysosomal Biogenesis
-Inclusion-cell (I-cell) disease, mucolipidosis II
-Protein Deficiency: GlcNAc-1-phosphotransferase (GlcNAcP-Tase); leads to defective sorting of most soluble hydrolytic lysosomal enzymes
-Accumulating Product: Lysosomal hydrolyses are not present in lysosomes
Disorders of the Lysosomal Membrane
1) Danon disease
2) Cystinosis
Danon Disease
-Protein Deficiency: LAMP2
-Accumulating Product: Presence of autophagic vacuoles
Cystinosis
-Protein Deficiency: Cytinosin (cystine transporter)
-Accumulating Product: Cystine
Centrioles
Visible in the light microscope, are paired, short, rod-like cytoplasmic cylinders built from 9 micro-tubule triplets. Centrioles have orthogonal orientation.
-Important Function: provide basal bodies, which are necessary for the assembly of cilia and flagella
Microtubule-Organizing Centers (MTOC)
Region where most micro-tubules are formed and from which they are then directed to specific destinations within the cell. The MTOC controls the number, polarity, direction, orientation, and organization of microtubules formed during the inter-phase of the cell cycle.
Kartagener’s syndrome
Causes dysfunction of microtubules, which affects sperm motility and leads to male sterility. It may also cause infertility in women because of impaired ciliary transport of the ovum through the oviduct.
Colchicine
Bind to tubulin molecules and prevent their polymerization; useful in the treatment of acute attacks of gout, to prevent neutrophil migration, and to lower their ability to respond to urate crystal deposits in the tissues.
Vinblastine and vincristine (Oncovin)
Another family of drugs that bind to microtubules and inhibit the formation of the mitotic spindle essential for cell division. Used as anti-mitotic and anti-proliferative agents in cancer therapy.
Trichome Staining purpose
Differentiates between nucleus, cytoplasm, and connective tissue fibers
Silver stain
Used to stain reticular fibers and nerve tissue
Elastic stains
Orcein, Verhoeff’s
What are inclusions?
They are cytoplasmic or nuclear structures with characteristic staining properties that are formed from metabolic products of cell
